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Industry Circles => Audio by Van Alstine => Topic started by: avahifi on 21 Nov 2011, 03:43 pm

Title: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 21 Nov 2011, 03:43 pm
For your convenience, I have compiled all the user reviews of our new Fet Valve 600R and 400R posted at AC so far all into this thread.  Check back from time to time as more information is posted here.

Thanks,

Frank Van Alstine

Tom Alverson

I have the Fet Valve 600R now and put it in my living room setup on my TV/computer system on some B&W 630i speakers I picked up used for about $400.  My "good" speakers are downstairs in my listening room which is not set up at the moment.  When I got these B&W 630i speakers I hooked them up to an old Transcendence amp and fed right from the sound card output of the PC.  It sounded pretty decent but the speakers sounded muddy in the bass (and compared to the current setup had much less clarity at all frequencies).  I now have the Fet Valve 600R hooked up to them being driven by the Vision combo preamp/dac fed from the SPDIF output of the PC.  The clarity at all frequencies is much better now and the bass better than I ever expected from these speakers.  They are spec'ed flat to 53HZ (2dB down).  I would much rather listen to this bass (even though it might lack a little reproducing movie explosions) that what I had before, even if I were to add a sub-woofer to the old setup.

If I had heard a subwoofer that gave me more power, weight  and visceral impact than I am getting now (which is pretty good) I might be interested.  My "good" speakers in my listening room go lower than this.

plaf26

Oh.  My.  Goodness! 

Have only had a few minutes to listen, but already, what a difference!  I say this every time I upgrade at AVA, but it's another layer of fog between the listener and the music removed.  Again am hearing more stuff I don't remember hearing before, even on a 55 year old mono LP! 

Frank asked me to start out without my subwoof on as I might never need it again.  I need more time to decide on that, but I'll say this: I'm hearing a lot more bass right now from my Maggie MMG's than I have a right to expect.

As always, Frank and his staff were most kind and helpful.  Homerun, AVA, thank you so much!!

NIGHTFALL1970


Anyone who is considering upgrading an AVA 350 to the 400R and is wondering if it is worth doing, it certainly is.  I notice that bass is tighter,  vocals are fuller and sound more life-like, and guitar sounds more "real".  I compared "stairway to heaven" from LED ZEPPELIN IV (Definitive Collection) on both versions of the amp.  Robert Plant sounded like he was in the room.  The solo at the end by Page sounded brite and shrill on the old version.  After the upgrade, the solo was smooth but not TOO smooth.  It sounded more like you would expect a guitar to sound like.

Next I wanted to try a good but poorly recorded album BLACK SABBATH "Born Again" (2011 Sanctuary Records Remaster).  The bass is muddy and the album is very "Noisy".  Iommi's guitar solo at the end of "Trashed" can kill a chicken!  After the upgrade the bass is tighter and more defined.  Iommi's solo is still brite,  but nowhere near as bad.  Ian Gillan's vocals sound MUCH better and life-like.  If this upgrade will make this album sound better than it ever has,  then imagine how nice STEELY DAN's "AJA" will sound.  If you are undecided about the upgrade, I highly recommend it.

aln

Several weeks ago, when I read about the new FET-Valve upgrade in this circle, I made a decision.  I would get another credit card, and upgrade my 550 EXR.  Once I received the credit card, I also purchased an Ultra 350 to tide me over while my amplifier was in at Frank's.

The Ultra was certainly cleaner than the EXR.  Transient attack and overall definition was superior as well as imaging information.  Yes things were better, and I enjoyed going through my music collection hearing parts of the mix that were subtly buried under the grundge that were a part of the EXR's performance. 

Yesterday, my upgraded Fet Valve 600R returned from Frank's.   I left work early so that I could retrive the amplfier from my back porch.  Downstairs it went and quickly it was hooked up, replacing the Ultra that I had been using.  I put on a Genesis SACD that was fresh in my mind as I had seen the concert only a few days before.  And I was stunned.  A complete layer of "haze" that was there with the Ultra no longer was there.  The music exhibited a "stark transparency" that was hard to believe.  After living with FET-Valve amps for 15 years this presentation was not just better it was completely better.  The distortion factor is so low that elements in the mix, the pans, the movements of the faders became immediately apparent.  Simply miked material such as Janis Ian had a voice that floated in its own space, with wonderful coherence and articulation.  Material with bass such as Steely Dan "Two Against Nature" was a revelation, as the mix's for the bass, drum and various synths was completely revealed.  Extension at both ends of the spectrum was well enhanced, more air, more low bass, and more spacial information for the material. 

I went upstairs and called Frank.  In the 30 plus years of sending him equipment I have never heard such an upgrade.  Whatever I sent him was ALWAYS better and well worth the money, but this upgrade was in another league.  I told him he hit a home run with this design and he hit it out of the park.  The best money I ever spent in audio.Ok,

I.Greyhound Fan

First let me take this opportunity to thank Mr. Frank Van Alstine for being so gracious and allowing me the privilege to do an in home audition of this wonderful amp.  And for all the other times he let me take home equipment.

Now for the review-

Equipment used-

AVA 600R power amp
AVA Ultra II preamp and Ultra II DAC
Modified Music Hall 25.2 CDP as a transport
Magnepan QR 1.6 speakers
Cables by Blue Jeans

I will list the music played at the end.

This amp is nothing short of spectacular.  When we first hooked it up, my 20yr old budding audiophile son and I noticed that it was a huge improvement over my Parasound A21(which strengths are dynamics,detail, bass, sound stage and transparency) and the FET Valve 550 that we auditioned a couple of years ago.  It was quite apparent that this is a special amp.  First off, the sound stage seemed to extend well past the walls of my 17'x17'x10' room.  The transparency of the sound seemed to have an almost holographic feel to it.  The spacing of the instruments was phenomenal.  I had to keep reminding myself that I was not listening to SACD's.  Even compressed older recordings like Fleetwood Mac opened up and became uncompressed with air and transparency.  Vocals and instruments were so life like that if you closed your eyes you got the feeling that Eva Cassady, Hope Sanduval of Mazzy Star or Johnny Hartman and John Coltrane were singing or playing in front of you.

The amp really showed its colors with classical music.  The quiet passages just sounded better and were more involving and the amp handled dynamic passages effortlessly.  The amp has great pace and rhythm.  The sound was grain free and the clarity, resolution and detail were on par with the $10,000 Ayres amp that I heard a couple of years ago and was better than my friend's $5,000 Nuforce Model 9se monoblocks.  Bass is powerful, smooth, deep crisp and well controlled.  It was the first time that I have heard my Magnepans produce that nice bass thump that you get with cone drivers.  Treble was natural and life like.  In fact, my son who plays the Sax in band commented that the amp produced the most life like cymbals that he has ever heard and I have to agree.  People who have heard my system have always commented on how life like the sound was but with this amp the music was eerily life like.  You get the feeling that you are sitting in the front row of an orchestra.

My only criticism if you want to call it that was that I had to do some tube rolling in my DAC and Preamp.  I use 6CG7 amprex in my Preamp and Tong Sols in my DAC which produce a slightly warmer sound with my Parasound, but with the 600R the sound leaned just a hint on the bright side with slight sibilance.  But once I switched to RCA clear tops in the Pre and DAC the amp was completely neutral with no real sound of its own.  But thats the beauty of tubes.  They sound different with different equipment and you can roll them to get the sound that you want.

So would I buy this amp?  Absolutely, it performs well above its price point just as all AVA gear does.  It is certainly on par or better than all of the amps that I have heard ( Ayres, Bryston, Theta, Luxman, Belle's, Nuforce, Parasound, Adcom, Jolida, Plinnius, Classe and MacIntosh ).





 


Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: plaf26 on 23 Nov 2011, 05:47 am
Ditto what others have said. All I can add is this: I've now had time to try all my sources.  My 400R dug music out of an old pre-recorded CrO2 cassette it never knew it had.  Same for a 40+ year old quarter track open reel prerecorded tape.  The quick clarity (aka transient response) of this amp enhances the perception of the music's timing, pace and rhythm.  For example, some modern classical pieces have some odd timing that up until now I dismissed as performance error.  Not with the 400R/600R.  There's no mistake, it's in the music on purpose.  Frank is right--this thing is "simply astonishing!" :o
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: kc8apf on 29 Nov 2011, 03:19 am
I've had my 400R for almost a week but doing a review with my current speakers (Definitive Technology Mythos ST) seems a bit pointless.  The amp is a precursor to upgrading speakers to a set of Salk SongTower RTs in a few months.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 7 Dec 2011, 10:53 pm
Lets get this thread back to owner's comments about the new 400R and 600R amplifiers.  There are a few of you I was hoping to hear from by now

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Hydro on 17 Dec 2011, 04:49 pm
I bought the 600R that Frank built over Thanksgiving. Been listening to it for over a week now and feel I have a pretty good handle on the sound. I replaced an Ultra 350 double in my main system that uses Soundlab A-1's. I tried it on my studio system that uses Elsinore diy speakers with an efficiency of about 90db. On both systems the first thing I noticed was the bass. Much more control, punch and extension. I can see why Frank suggests trying this amp before buying a sub. I have found that I like the way Gold Lion Genalex cryo reissue tubes sound in these amps. I used the supplied JJ's in my Ultra DAC and really like them there. Didn't like the Gold Lions in the dac. The Gold Lion's give the sound a very lifelike feel and really get the phasing of guitar pedals right. They might be a little etched sounding for some tastes. Back to the 600R, after getting used to the bass of the new amp I was able to concentrate on mids and highs. In my efficient studio system I didn't notice that much difference from the Ultra 350 dd, but on the very complex and inefficient load of the Soundlab electrostats there was a big change. Everything has the immediancy of live. Image is rock solid and there are layers of sound I had never heard before. I will not be sending this amp back on the 30 day trial. Thanks Frank for another great product.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 19 Dec 2011, 08:21 pm
Thank you Hydro, for your kind comments about your new Fet Valve 400R amplifier.

I notice other threads here at AC regarding the efforts of users to get better bass from their systems, often wondering what subwoofer to graft onto the bottom end or whether a tuned port would work better than a infinate baffle or so on.

Hardly ever do they wonder if their electronics ahead of their speakers might be the issue.  I have often suggested that your system won't play bass if the electronics ahead of the speakers don't reproduce bass properly.

Those of you with a Fet Valve 400R or 600R amplifier know what I mean.

Merry Christmas!

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 20 Dec 2011, 10:10 pm
Okay. I guess I'm next. This is my review of the 600R, which is the current version of my amp. I went from a FetValve EXR5 to an Ultra to an Ultra Double+ and now to the 600R, all via upgrades. In all cases for my listening rig I've used TFK ECC801S tubes.

Compared to the previous versions of the amp, the 600R is transparent transparent transparent. More so than I would have expected given how well I thought previous version of this amp portrayed the musical space. The very sense of the actual recording space is so clear now. The clarity extends into the deepest parts of the soundstage. No grunge at all coming from the speakers. In this, I'm not diminishing the previous versions of the hybrid, but the 600R does provide a cleaner, larger, more clearly defined 3 dimensional space. Very subtle musical cues which I had a hard time picking up on before are now more easily picked out of complex pieces when a lot of instruments are going.

The music also seems "faster" (improved transient performance - is this because of the improved regulation?). The sudden shifts that occur in some pieces of music (especially small ensemble acoustic jazz) grab my attention more than with the earlier versions. But the amp doesn't do this by being hard or edgy. It’s neither hard nor soft; double bass and bass drums have that proper organic “meaty” quality without being blurred. Trumpets and violins have the proper screech when called for. If you’ve heard either one live when the musician is really setting fire to them you’ll know what I mean. In the past I’m not sure I got as clear a sense of that – especially on trumpets with that neat combination of burnished brass but metallic bite.

The clarity goes from top to bottom. It's better in the top but gets progressivley more better :icon_lol: as you go to the lowest octaves. Yes, the bass is way better than it used to be - more spacious, more articulate, more powerful. But take that with a grain of salt. If your speakers are capable of reproducing the lower octaves you will get much better sound out of them. If not, well, it's better but there's no substitute for a larger enclosure and larger drivers. Let's say you'll get probably the best bass you've ever heard from whatever speaker you've got. :green:

What else is there to say? The front to back position relative to the speakers seems about the same. I first wondered if the 600R was setting the image a bit further back because of what I was hearing with the improvement in depth, but that was an error in my judgement.

Are there any negatives? I don't think so. I wondered briefly if the heroic amounts of regulation might cause the amp to "overdamp" the music, but I'm not convinced of this. What had me wondering about this was when I was listening to the Ondine recording of the Philadelphia Orchestra playing Saint-Saëns Symphony Number 3. I was actually at this performance when it was recorded, and heard it again a couple of weeks ago with Philly, but this time conducted by Marin Alsop. I sit in orchestra center about 10-12 rows back. In this piece there are a couple of points where the triangle is struck. When you hear it live the sound almost "shimmers". It just floats along in space for a while, until it gives up it's energy and disappears. When I played the recording at home the same triangle moments were clear, but seemed more matter of fact. There wasn't the same kind of "hang time" as when I heard these live. Is it because of the way the mics were placed? The way the recording was mixed or processed? Could be. Over-regulation in the amp? Not as sure about that but I don't think so. Too many variables.

Don't misunderstand me, my feeling about the 600R is nothing but positive. I haven't heard better in my system - ever. Look at what I'm doing: I'm sitting here talking about comparing a live event to a recording coming out of my home system! Before the 600R I'm not sure that kind of crazy talk would have been possible. Is the 600R better than any previous version I've heard of Frank's hybrid design? Yes. Should anyone looking for a better amp consider it? Yes.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: martyo on 21 Dec 2011, 10:43 am
Sounds pretty amazing Tony. Interesting comment about over-damped. Sometimes class D amps are praised for their bass response. The ones I've listened to all sounded over-damped (in all the frequencies) and there was no "proper organic “meaty” quality" to the bass. I'm very envious dude!
Thanks for the excellent write-up, ENJOY!! 8)   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: mark funk on 21 Dec 2011, 11:04 am
Ya, sounds like you like it.  :thumb:




                                                                                        :smoke:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 21 Dec 2011, 12:50 pm
Sounds pretty amazing Tony. Interesting comment about over-damped. Sometimes class D amps are praised for their bass response. The ones I've listened to all sounded over-damped (in all the frequencies) and there was no "proper organic “meaty” quality" to the bass. I'm very envious dude!
Thanks for the excellent write-up, ENJOY!! 8)

Yes, I've heard Class D amps a number of times (but not driving my speakers) and I've heard that real overdamped quality. Takes some of the life out of the music. The 600R is not like that at all (no fear of that).

As I said, in my case I very well could have heard exactly what was on the recording. The last time I'd heard it through my system was too far back for me to remember this bit of subtlety.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 21 Dec 2011, 03:38 pm
Received my 400R yesterday and put into my Rebuilt Maggy IIIa system, cold out of the box the sound is quite good.  Bass is amazingly full, mids are round and sweet. Highs seem lacking a bit.
I can easily hear some of the magic, the enveloping of the music around me, but I am worried about the highs.
My test recording for is the Women of the World celtic cut called "Raindance"  The first few seconds is simulated Rain that is clearly heard from my seat with other amps, but was missing with the 400R. I had to put my ear to the ribbons to hear it.  To double check I put back another amp (250w/ch classD audio, cheapy) and the rain sounds were there clear as day.
So I put the 400R on the bench to burn in for the next 100hrs with pink noise (my cat hates this, I do need to get some big R's for this) to see what happens.
I will post again after the burn in....
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 21 Dec 2011, 03:43 pm
Thanks for the thoughful and favorable review, Tony.

Regarding the concept "overdamped," this just is not possible with our power supply designs.  Since they always are available to supply instant current, instantly fast, with way more capacity and no interaction between devices that the audio circuits could ever possibly demand, they drastically improve transient response and overall clarity and bass response than possible with any other configuration.  Go back and listen to any old DMP CD to hear the highs just float out into mid-air.

For most users, the amazing clarity and imaging and just awesome bass depth and tonality and impact will be the best improvement they ever did to their audio system.  For many, a Fet Valve 400R or 600R will also eliminate their yearning for a subwoofer too.

Even Stereophile, which normally never gives us the time of day, reported that at this summer's California Audio Show, that the Salk room had the best bass at the show.  Of course they never reported that is was all AVA Fet Valve equipment driving the Soundscape 10s at that show.  Evidently the astonishing bass just appeared out of thin air.  Secret tip, it was us there driving the Soundscapes,  really!

Best regards,

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 21 Dec 2011, 04:07 pm
Thanks for the thoughful and favorable review, Tony.

You're welcome, Frank. I try to be as objective as possible, which some may misunderstand since the audio rags tend to portray things with an extremist mentality. The 600R is a big step up in amplification.

Regarding the concept "overdamped," this just is not possible with our power supply designs.  Since they always are available to supply instant current, instantly fast, with way more capacity and no interaction between devices that the audio circuits could ever possibly demand, they drastically improve transient response and overall clarity and bass response than possible with any other configuration.  Go back and listen to any old DMP CD to hear the highs just float out into mid-air.

I suspected you had a solid explanation. :)

Interesting what pelliott321 said.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 21 Dec 2011, 05:09 pm
 :scratch: No highs?  gonna "burn it in", double huh?  What do you think Frank does when they test and before shipping.  What "burns in"?  Perhaps you have a defective unit?  Another very rare first?   Ya gotta explain how playing it for 100 hours will somehow bring something, that ain't there now?  If it's a defective ckt, nothing.  Why Pink, isn't White noise even better? 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: AVnerdguy on 21 Dec 2011, 05:33 pm
I was evaluating the 600R and speaker combo for a few weeks before commenting.

I had a FET Valve 550 w/double die option which I had for just more than a year. When I purchased that model I was pleased at how much more detail I was hearing with materials I was very familiar with. The amp was very precise (only way I can describe it) with tight bass and very clean highs. Cymbals and brass instruments were reproduced with amazing clarity and the depth of the soundstage was outstanding. I was running it into a set of Maggie 1.7s which was a great combination.

Decided I wanted to try the Maggie 3.7s which had just been introduced. At almost the same time AVA announced the 600R mod for my current amp. After a long hard investigative process I decided that was too hard to pass up. However, I was wondering just how much better could it be over the FET 550 and was I just throwing around cash and getting into the next best thing that comes along cycle.

I am delighted to say that the 600R is better. The bottom end is tighter with more definition on bass notes.  It seems to have more drive down low. The high end is silky smooth and I’m not sure if it’s the amp or the speakers but where there used to be slight bit of harsh edging on brass instruments at high volumes is now gone. The soundstage is wide and deep. The individual instruments that used to get lost are all now independently recognizable and I find myself picking out a single instrument to follow through a song. Amazing to find out how much was going on in the background. Backup singers are individual voices easily distinguished whereas before they were grouped together. It is easy to place the location of instruments or vocalists within the soundstage.

Again, new speakers and a new amp at the same time make it difficult to point to which was the greater improvement. However, I believe the amp was a definite improvement and drives the 3.7s effortlessly. I find that I am listening at higher volumes with less fatigue. I don’t realize how loud it is until I turn it down and I attribute that to how clean it is. The amp is absolutely noiseless and can go from whispers to crazy loud volumes with astonishing speed and detail (has caught me off guard a few times). Never a hint of harshness or breakup.

On a side note – I think it dissipates heat a little better than the 550. I might be imagining that but the cabinet is not as warm as it previously was.

A solid upgrade to an already great amp. I am very satisfied with the improvements and highly recommend it to anyone thinking of upgrading a previous version.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rcag_ils on 21 Dec 2011, 05:51 pm
Quote
Even Stereophile, which normally never gives us the time of day, reported that at this summer's California Audio Show, that the Salk room had the best bass at the show.  Of course they never reported that is was all AVA Fet Valve equipment driving the Soundscape 10s at that show.  Evidently the astonishing bass just appeared out of thin air.  Secret tip, it was us there driving the Soundscapes,  really!

Best regards,

Frank Van Alstine

Maybe my comment is totally unrelated to this thread, but it's just plain poor journalism, not to mention unethical.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 21 Dec 2011, 07:00 pm
festuss:
I am just reporting what I hear, which is what this thread is for.  It was a pretty positive report for a new unit out of the box.
Is this a place for AVA zealots or for real information? Turn your flame down and you will live longer.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 21 Dec 2011, 09:51 pm
Festuss, I don't think it is really appropriate to subjectively discuss what someone else claims to hear, or not hear, in this thread.

I welcome all inputs here sticking to the topic of their own thoughts about new Fet Valve amplifiers.

I do note that pelliot's comments seem somewhat non-typical, especially since the 3 dB down points are 4 Hz and 350,000 Hz.  I suspect that there is a real difference beween his previous amp and ours and that he is simply used to the high end performance of the old one, even if it actually has more extreme high end output than it should have.  Time will tell,  but I agree that we don't think break in time is of much value.

Just stay back and enjoy the comments.  Maybe they will convince you to try a Fet Valve 600R or two yourself.

Merry Christmas.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 21 Dec 2011, 10:30 pm
I do note that pelliot's comments seem somewhat non-typical, especially since the 3 dB down points are 4 Hz and 350,000 Hz.  I suspect that there is a real difference beween his previous amp and ours and that he is simply used to the high end performance of the old one, even if it actually has more extreme high end output than it should have.

I've spent a bit of time over the years listing to Maggies (yes even back to the IIIa). As I recall they are a bit of a difficult load to drive. I say this with some confusion, as the FetValve has always been known as something that could drive the most difficult sorts of loads. pelliott, which amp were you using previously?

In reviewing the reviews so far, I think only pelliott and I made any sort of specific elaboration on the high end. I'm approaching this question with caution as I think in my case I can explain it, but I'd like to ask the other reviewers if they could chime in with some additional thoughts on this end of the spectrum.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rockadanny on 21 Dec 2011, 10:55 pm
In reference to the HFs ... Do cymbal strikes sound like plastic-tipped wood stick striking brass? Or is it more of a generic metallic sound?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: AVnerdguy on 21 Dec 2011, 11:11 pm
I think the cymbals are the best I've heard. Hard to say if it's the new amp or the new 3.7s BUT they sound just like when I'm jammin with the guys in the basement. Sharp attack with great decay and sound so smooth - no brash/harsh sound. You can hear the strike and can tell where they hit it depending on how they hit it.

Brushes on a snare are outstanding as well. I can hear a pick on the strings and the reeds rattle on a sax on quiter recordings. Subtle, not emphasized but just there.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 22 Dec 2011, 12:09 am
I think the cymbals are the best I've heard. Hard to say if it's the new amp or the new 3.7s BUT they sound just like when I'm jammin with the guys in the basement. Sharp attack with great decay and sound so smooth - no brash/harsh sound. You can hear the strike and can tell where they hit it depending on how they hit it.

Brushes on a snare are outstanding as well. I can hear a pick on the strings and the reeds rattle on a sax on quiter recordings. Subtle, not emphasized but just there.

Cymbals are interesting. Their fundamentals go up only to about 1 KHz, but the upper harmonics can go up to about 15 KHz or so. When I hear them in concert they don't seem to have as pure a decay quality as something like a triangle. Where the triangle remains very pure during its decay, the cymbal sound tends to get homogeneous. Maybe it's because the fundamental range is so wide to begin with.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 22 Dec 2011, 12:18 am
Cymbals are a strange instrument. They actually start to create canceling wave forms by themselves. When 2 or more are hit in a short period of time, they begin to have some in-phase/out-of-phase stuff going on. It's that acoustical "pressure ridge" ting going on. I hear it all the time in recording music, and most of the time with live music. The problem is the instrument itself, as it moves in an odd and diffusing manor when stuck with a drum stick.

Wayner
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: jtwrace on 22 Dec 2011, 12:21 am
Have you guys seen this?

http://www.youtube.com/watch?v=kpoanOlb3-w&feature=related

These are pretty cool too.
http://www.hammerax.com/liquicy.htm
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 22 Dec 2011, 03:06 pm
Tonyptony/AVA:
First off let me say unequivocally, that I like very much what I heard with the 400R in my system.  The bass is big and fast and the mids are beautiful, warm and evolving.  What I am missing is the "Air". I clearly said this in my first post here.
I have used various amps.
The main purpose of getting the 400R is to replace a pair of dbSystems 150w mono-blocks I bought used in 1995.
These were known as dark, laid back amps.  The high freq, low level detail I was talking about is clearly audible with the dbsystems amps but not the 400R.   This is true with the very cheap class D audio cds 254.
I have also have a TAD-60 50watt KT88 Chinese amp and even had and ultravalve for awhile which did not have enough umph but clearly produced the high end I was use to with my maggy's 
I have another day of break-in (even though Frank poo-poos the idea, I just do this will all equipment I get in) and I will evaluate again, I will run graphs. 
I can work with the ribbons xover, very easy to pump it up, if I choose to keep the 400R, I have 30days to work it out
What I was hoping for for constructive help, not implying that I am crazy or stupid or wrong.  I hear what I hear.  In my 40 years with this hobby I have admired Franks work, even used some of his ST-70 stuff, But I am a realist, I do not blindly follow with my tongue dragging on the ground the great god AVA.   
   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: jtwrace on 22 Dec 2011, 03:10 pm
Tonyptony/AVA:
First off let me say unequivocally, that I like very much what I heard with the 400R in my system.  The bass is big and fast and the mids are beautiful, warm and evolving.  What I am missing is the "Air". I clearly said this in my first post here.
I have used various amps.
The main purpose of getting the 400R is to replace a pair of dbSystems 150w mono-blocks I bought used in 1995.
These were known as dark, laid back amps.  The high freq, low level detail I was talking about is clearly audible with the dbsystems amps but not the 400R.   This is true with the very cheap class D audio cds 254.
I have also have a TAD-60 50watt KT88 Chinese amp and even had and ultravalve for awhile which did not have enough umph but clearly produced the high end I was use to with my maggy's 
I have another day of break-in (even though Frank poo-poos the idea, I just do this will all equipment I get in) and I will evaluate again, I will run graphs. 
I can work with the ribbons xover, very easy to pump it up, if I choose to keep the 400R, I have 30days to work it out
What I was hoping for for constructive help, not implying that I am crazy or stupid or wrong.  I hear what I hear.  In my 40 years with this hobby I have admired Franks work, even used some of his ST-70 stuff, But I am a realist, I do not blindly follow with my tongue dragging on the ground the great god AVA.   
 

Good for you!  I very much look forward to your results.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 22 Dec 2011, 04:39 pm
Good for you!  I very much look forward to your results.

What does that mean? Any piece of equipment is only a link in the chain. I hate to over use this word, but it is synergy. In my studio I have 4 different amps (not all AVA, most SS), 2 preamps and the combinations of sounds I can get are amazing. No amp sounds alike, but neither does any preamp. It's all up-stream and down-stream stuff, that makes the complete system "bloom" and produce air. Sometimes, it could be the power conditioner, who knows. Experimenting is always in order with any new piece. I've even had to change speaker spacing and toe-in with different amps. Remember that Frank's new amps have tremendous speed and high slew rates.

Wayner
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 22 Dec 2011, 05:47 pm
I give up
Is any one reading what I am saying here, are you blind, deaf, or just dumb.
The only thing I am changing is the amp. I am just reporting what I am hearing, which is what this thread is for.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 22 Dec 2011, 06:52 pm
Guys, before things start getting out of control let me try to address both pelliott's and Wayner's points. I do agree that introducing a new component - in this case an amp - into an otherwise set system can and very well may introduce a change to the overall musical experience. I said this before but I'm still finding it hard to understand given Frank's care in design - is it possible there's something about the way the "R" series output could possibly interact with Maggies to explain this? I know AVnerdguy has 3.7's, but the older Magnepans like the IIIa's I think may present a different sort of load characteristic compared to the newer ones. Be nice if Jim Winey could step in and comment on this.

Having said that, in my case I've been through three previous versions of the FetValve design. While I cannot make the same sort of statement regarding a loss or reduction in high end as made by pelliott, I'm convinced now there is something different about it. I've spent hours listening to pieces of music where pure, uncomplicated high frequency sounds would previously project themselves upward into the same sort of physical space that we now get in front to back form with the "R". With the "R", the frequencies are still pure and present (in my case), but they sometimes seem "held down" - like the upper space they used to project into is no longer there.

Am I being fooled? Maybe. It's possible the improvement in the size, depth, and clarity of the soundstage is putting things into a more balanced perspective. I don't know. I still love the way this thing sounds, but there was a certain bell-like quality to the EXR5 and the Ultra which has changed somewhat starting with the Double+ and through the "R".

BTW, my hearing is still as good as it was back then. Just had it checked in late spring.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 22 Dec 2011, 07:01 pm
Every time I have had my amps (or even preamps) upgraded, I've had to reposition my speakers. Don't ask me why or give you a detailed explanation, I cannot. I do believe as the upgrades present even faster components and better execution of these components, affects the sound stage.

That said, I do not believe it is possible to simply interchange an amp, without something downstream being affected, and it is almost always the speakers. Perhaps they need to be farther in, or farther apart, toed in more, or less. But I think you will find that doing this will bring back the so called "air" that you think you have lost. And sometimes, it's a very small amount of movement that changes the sound field and it's content.

That is my point.

Wayner
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 22 Dec 2011, 08:07 pm
I find the comments herein regarding the very high frequency performance of the new Fet Valve 400R and 600R amps to be very interesting and not at all annoying.

I have no problems at all with you all reporting it as you hear it.

The main speakers I use here for component evaluations are Salk HT3s.  They are  large and robust three way design with ribbon tweeters.  I also use a set of B&W 801s of a completely different design basis just to make sure I am not designing amplifiers for a specific amplifier.

I should note that many of the guys working for me have expressed dislike for the Salks.  They commented that they were just too bright edgy.

Over the years, as we have significantly improved the high frequency linearity of our amplifiers, their dislike has significantly reduced.  Now the Salks are appreciated by all here.  We still get the high frequency detail, air, and transparency as before, but the last trace of grain and brightness has been removed.  Note that the frequency response of the amp has not been compromised, they still are ruler flat past 200KHZ (-3dB at about 350KHz) and square wave performance is perfect, no leading edge overshoot at all.

Of course no amplifier is perfect for every speakers.  We try and design so the speaker load will not interact with the amp at all and have the clean power available to drive anything.  The amps also have a  very high input impedance so they are easy loads for a preamp to drive.

Of course this may sometimes cause an unanticipated interaction with interconnect cable or speaker wires of non-standard electrical values.  Sometimes we suggest going  back to a low cost simple coax shielded cable to see if some exotic interconnect cable or speaker wire is modifying the results unknowingly. This is always worth trying if your results are not what you expected.

We would ask that if the high frequency performance is not what you expected, please search your entire system for a possible culpert. Most new owners simpy love the amps and report back exactly what we had hoped for. Any help you can give us to identify negative interactions will help us advise all clients how to get best results with these new and unique designs.

Thanks again for your comments.

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 22 Dec 2011, 08:20 pm
Last night I plugged in the 600R that had just arrived. When I listened to it, my jaw kinda dropped. I will have to do a more detailed review but an immediate improvement in detail is obvious wrt dialogue and song lyrics. I was halfway through watching a movie that had a really difficult dialogue track when the new amp arrived and the rest of the movie was completely intelligible--now that was just plain serendipity. Then I put in one of my latest addictions, Shakira's Greatest Hits and I could finally understand more or less all her lyrics (as long as they're in Spanish ;) ), without even making much of an effort to concentrate; I also noticed a rumbling quality to the bass in that album that is just nice. The 10,000 Maniacs "thump" seems to have gone away somewhere (Mars, hopefully), and this morning when I put on American Beauty, dammit Frank, I could hear details of Jerry's duets with Grisman on "Ripple" that I always suspected were there but could never confirm as directly as now; in general, the percussion is much sharper including that thing where they do a quick repeated tapping on the whatever (maybe the cymbals).

It's not just detail, though. The imaging and soundstaging has gotten ridiculously good. It resembles a headphone effect, with the whatever jingling right next to my ear.

I haven't had a chance to hear some classical music yet, but I'll get out the Brandenburgs and read the score along just for a chuckle. And my ultimate percussion test, Santana's Moonflower...

My AVA journey began as a "permanent replacement" of my Stax headphone habits, with the Fet Valve Ultra 550, through a pair of 550s in monoblock, to a Double 550+, and now the 600R. I was always very happy with whichever one I had (and rather surprised that there was a match for the clarity of the Stax), and continually gobsmacked when the new kid in town improved on what was already there. This 600R is no exception.

Of course no new arrival goes without the popping of the hood. Things inside look quite tidy, and you could build a springboard for your pool with the pcb boards; so servicing these puppies should be simultaneously easy and unnecessary...

Frank, I don't know what digit beyond the decimal point of distortion you were working on in this latest iteration, but no matter how far along it is, the improvement is still lovely and audible. Congratulations on a fine achievement.  :thumb:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 22 Dec 2011, 08:32 pm
We would ask that if the high frequency performance is not what you expected, please search your entire system for a possible culpert.

Frank, rest assured that in my case it's not "not what I expected", but more "hmm, this is different, I wonder why?". I will admit to not having taken Wayners advice to try and reposition my speakers ("But they've always sounded good where they were!" :)). There may be something to that.

BTW, I am vey familiar with the HT3s. Two of my audio friends have them. I agree the high end can be interesting if not driven properly, but when it is it's quite something.

Happy holidays to all.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: dlparker on 22 Dec 2011, 09:05 pm
I find the comments herein regarding the very high frequency performance of the new Fet Valve 400R and 600R amps to be very interesting and not at all annoying.

I have no problems at all with you all reporting it as you hear it.

The main speakers I use here for component evaluations are Salk HT3s.  They are  large and robust three way design with ribbon tweeters.  I also use a set of B&W 801s of a completely different design basis just to make sure I am not designing amplifiers for a specific amplifier.

I should note that many of the guys working for me have expressed dislike for the Salks.  They commented that they were just too bright edgy.

...

Thanks again for your comments.

Frank Van Alstine

This brings up an interesting point, and one I'm very interested in - "whose ears"?!?

If I remember correctly, Frank hit 74 recently, and I hit 65 in July.  In addition I have tinnitus which starts somewhere between 9&10 kHz.

Although it's not specifically pertinent to the 'strictly' AVA nature of this thread or forum in general, I'd like know what others have experienced in this regard in relation to the current subject of high end response and individual 'ear response' (is there such a thing?) curves.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 22 Dec 2011, 09:09 pm
I should make it clear that I listen in near field conditions and I hear everything. That also means that I notice everything, too. I'm only expressing my interests here, as I have been down this road a time or two, and while some amps do have little impact, others may be different. Just mark your original locations so you can move them back to where you had them. I will also admit that my obsessive disorder kicks in when it comes to speaker placement, as mine are probably within 1/32" of mirror condition to each other.

Again, I have no explanation for this, but I suspect component speed increase.

Have fun.

Wayner  8)

BTW, Frank is not the only one that listens to new prototypes, there is an entire crew, Dean, Dr. Dean, Larry, Mary, Nate and others.

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: dlparker on 22 Dec 2011, 09:27 pm
Thanks Wayner.  I'm definitely having fun.  And generally extremely happy with my my most definitely suspect hearing and the huge improvement in my musical listening experience since I first entered the AVA world in July of '10, after more or less 40 years of interest in Frank's stuff.

I should make it clear that I listen in near field conditions and I hear everything. That also means that I notice everything, too. I'm only expressing my interests here, as I have been down this road a time or two, and while some amps do have little impact, others may be different. Just mark your original locations so you can move them back to where you had them. I will also admit that my obsessive disorder kicks in when it comes to speaker placement, as mine are probably within 1/32" of mirror condition to each other.

Again, I have no explanation for this, but I suspect component speed increase.

Have fun.

Wayner  8)

BTW, Frank is not the only one that listens to new prototypes, there is an entire crew, Dean, Dr. Dean, Larry, Mary, Nate and others.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: jtwrace on 22 Dec 2011, 09:28 pm
What does that mean? Any piece of equipment is only a link in the chain.
Wayner
Of course but the man gave an opionion on how it sounds in his system.  Whether he likes the sound or not is secondary to how he's been blasted.  Maybe it (the amp) will come around for him and maybe not.  He hears what he hears and that's all there is to it.  We all hear differently subjectively. 

The AVA amps might not be for everyone and if one doesn't agree with the AVA sound it should be acceptable for them to return the amp with the fantastic return policy that AVA has in place.  That's what it's for.   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 22 Dec 2011, 09:38 pm
Who blasted him? Me thinks your looking for some street action. Keep diggin'

W
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: jtwrace on 22 Dec 2011, 09:50 pm
Me thinks your looking for some street action. Keep diggin'

W
What's that?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 22 Dec 2011, 10:17 pm
Peace here please!

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 23 Dec 2011, 02:12 am
Over the years, as we have significantly improved the high frequency linearity of our amplifiers, their dislike has significantly reduced.  Now the Salks are appreciated by all here.  We still get the high frequency detail, air, and transparency as before, but the last trace of grain and brightness has been removed.

Frank, what engineering parameters are factors in the reduction of grain and brightness? How is "brightness" differentiated from high frequency extension? Fellow engineers would appreciate the elaboration.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 23 Dec 2011, 04:22 am
Clearly the sound of the amp is system dependent.  I did an intial review of the 600R when Frank loaned me the amp. I paired it with a modded Ultra preamp and modded Ultra DAC along with my Magnepan 1.6's.  The amp had tremendous air and transparency with the best treble and high frequency resolution and detail that I have heard.  However, the sound leaned slightly on the bright side until I rolled some warmer sounding tubes in my preamp and DAC.  In Franks studio with the HTR3's I did not notice any brightness.  I found the speed and attack of this amp to be phenomenal.  If any if you guys want to sell your 400 or 600R give me a PM.  I would be more than happy to take it off your hands :D
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 23 Dec 2011, 05:45 pm
Tony asks what engineering parameters are factors in the reduction of grain and brightness?

Good question, there is no simply answer we are aware of other than doing our best to design circuits that improve linearity, even if we cannot measure the changes with our test equipment.

In our big hybrid power amplifiers, I can kind of give you a time line of the things that have been improved over the years.  Each made easily audible improvements in musicality and reduction of grain and listening fatigue, but almost none can be observed with our test equipment.

Probably the first important improvement was going from the original Hitachi power mos-fet output devices to Exicon devices.  This change was forced upon us as the Hitachi devices went out of production.  The only circuit changes necessary were an increase in the value of the gate resistors from 100 ohm to 220 ohm to insure high frequency stability.  The musical differences were obvious, not only in our hybrid amplifiers, but in our solid state amplifiers too.  The most notable audible effect was a sense of "sparkle" and life to the high end previously missing.  That and a feeling of overall clarity too, with no negative effects at all.  The necessary changes in gate resistor values told us the Exicons were faster devices, but nothing at all different about them we could see up to the three meg limit of my generator and scope.

Another fairly early change was done to eliminate a hump in the ultrasonic frequency response around 200K Hz.  Way up there beyond the hearing of bats, the square waves were not perfect.  We finally traced the issue down to the outputs being slightly loaded by the protect zeners installed to make sure that the allowable gate voltages were never exceeded.  Changing one set of 1000 ohm resistors to 100 ohms fixed this issue.  It also made another useful reduction in grain and brightness in the hybrid amplifiers, of course with no measurable effect other than that now ultrasonic square wave performance was perfect.

Much later, Dean Kayser, our resident EE expert, suggested that the same active regulated power supplies that we had installed in the hybrid and tube preamplifiers would also be useful in the hybrid amplifiers.  This required a new multi-stage power supply board, with active regulators for the tube and for the mos-fet in the small signal transimpedance loop.  We did regulated power supplies for each tube heater at the same time.  This provided a major improvement in overall clarity and musical involvement. Again, we could hear it and knew that it was better engineering, but could not measure it within the capabilities of our test equipment.

That next step was finding a replacement for the Hitachi J79 mos-fet being used in the audio circuits.  This was a tough one because there seemed to be no suitable replacements out there.  We finally decided to give the Exicon 10P20 plastic case mos-fet a try as it had the voltage and current requirements, but somewhat higher gate capacitance.  In spite of this, it made a major improvement musically.  Evidently the Hitachi had some unpublished characteristics that was limiting its value in a music amplification application, again something we cannot verify on the test bench but certainly can hear.

More recently, we had the entire audio circuit reanalyzed by an outside EE and he came up with only one useful new suggestion, that the capacitor across the bias pot was limiting internal bandwidth, the effect being masked by the feedback.  That part went from one micro-farad to 10,000 micro-farads, with another improvement in overall musicality and purity.

Finally, in the release before the current new production Fet Valve 400R and 600R amplifiers, we redesigned the audio boards to allow one more active regulated power supply per channel, so that the tubes no longer had to share one supply per channel, now each tube plate and the accompanying mos-fet each had their own independent active regulated power supply.  Again an engineering improvement we knew would be worthwhile, but as usual, not one we can measure, except with our ears.

The final breakthrough has been providing active regulated power supplies for the output transistors themselves.  This is a tough one, as since all the current supplied to the loudspeakers has to first pass through the power supplies, each active regulated power supply must have at least the same current and thermal capacity as the output mos-fets do themselves.  We were able to meet this goal with a clever use of the new Exicon double die mos-fets.  Two in parallel per channel with a zener reference, provides the amazingly stable active regulated power supply we were looking for.  An added benefit is that the amp runs cooler as the output devices no longer see the whole hear 200V raw power supply rails, just the appropriate lower regulated rails.  The regulator devices run very safely too.  At idle, they see high voltage but no current draw.  At clipping, they must provide very high current, but as the raw supply pulls down from demand, the voltage across the regulators substantially decrease, keeping them always in a secure safe operating area.

As usual, nothing new to see on the test bench.  The bandwidth (3 dB down at 350KHz and 4Hz) remains the same and square wave performance is still perfect and the slew factor remains infinite. However, as all of you have reported, the overall musically of the new Fet Valve 400R and 600R is quite amazing.

So, what engineering affects grain and brightness?  All of the above.  Just lots over very hard work applying improvements that we know are good engineering efforts even though the test bench does not give us much help.  I think the Fet Valve amplifiers are a done deal now, unless, of course, the future reveals new concepts to try.  Right now I am just enjoying the music.

Best regards,  and Merry Christmas,
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 23 Dec 2011, 06:50 pm
So, what engineering affects grain and brightness?  All of the above.  Just lots over very hard work applying improvements that we know are good engineering efforts even though the test bench does not give us much help.  I think the Fet Valve amplifiers are a done deal now, unless, of course, the future reveals new concepts to try.  Right now I am just enjoying the music.

Best regards,  and Merry Christmas,

Frank, I can't tell you what a big smile is on my face after reading your comprehensive and willingly offered summary of design improvements for the FetValve. It makes my engineer's heart proud to hear how you worked through to the result we have now - even if some of it can't be measured! :beer:

Merry Christmas to you and the whole AVA family. :xmas:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: dlparker on 23 Dec 2011, 07:09 pm
Quote

from: avahifi on Today at 05:45 PM

     So, what engineering affects grain and brightness?  All of the above.  Just lots over very hard work    applying improvements that we know are good engineering efforts even though the test bench does not    give us much help.  I think the Fet Valve amplifiers are a done deal now, unless, of course, the future reveals new concepts to try.  Right now I am just enjoying the music.

    Best regards,  and Merry Christmas,

Frank, I can't tell you what a big smile is on my face after reading your comprehensive and willingly offered summary of design improvements for the FetValve. It makes my engineer's heart proud to hear how you worked through to the result we have now - even if some of it can't be measured! :beer:

Merry Christmas to you and the whole AVA family. :xmas:

See what I mean?  This is more evidence in support of my theory that Frank is in fact the real, genuine, dyed-in-the-wool Santa Claus!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: AVnerdguy on 23 Dec 2011, 07:45 pm
  An added benefit is that the amp runs cooler as the output devices no longer see the whole hear 200V raw power supply rails, just the appropriate lower regulated rails. 

So I wasn't imaging things! I thought the amp ran cooler than the previous version. Good to know.

Great amp with outstanding performance. I hate to say it but this will be the last thing I buy from AVA - it's so good I have no reason to and I'll be using this one for many years to come. Well, maybe many years down the road I'll replace the AvaStar with the new Fet Valve that is....... :D

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rlee8394 on 23 Dec 2011, 07:46 pm
Frank,

That is a great explanation on the circuit enhancements for the amps. Many of us engineers and technical folk appreciate that kind of circuit description over the usual marketing speak. That's the kind of information that makes your equipment even more valuable in my estimation. I miss that kind of detail that I used to get from your Audio Basics newsletter. Wish you had more time to elaborate on all of your designs in that matter. As tonyptony said, we do appreciate the elaboration.

Congrats to you and your team for continually designing exceptional equipment. Looking forward to new AVA products in 2012.

Ron
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: mark funk on 23 Dec 2011, 08:07 pm
Oh, I miss Audio Basics. This sounded just like it! Wish we had more. Keep it coming Frank. :thumb:



                                                                                         :smoke:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: plaf26 on 23 Dec 2011, 08:20 pm
Quote
now ultrasonic square wave performance was perfect.

Aha, thought so!  Been wondering what that square wave response is like.  Bravo!  I'm one very happy 400R owner! :singing:

Merry Christmas, everybody!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 23 Dec 2011, 09:26 pm
In our big hybrid power amplifiers, I can kind of give you a time line of the things that have been improved over the years.

...

Best regards,  and Merry Christmas,

This is a lovely present to us and to the whole audio community. Thanks Frank and team AVA!  :thumb: :thumb: :thumb:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: modular747 on 24 Dec 2011, 05:10 am
Frank, thanks for the excellent discussion of your circuit developments.  It also provided clear insight into how you and your team go about the quest for improvement. 

It's not surprising that standard measurements fail to show the sonic improvement (or just change for that matter), with the circuit changes mainly involving power supply and component updates.  I'm wondering if the new Fet-Valve preamp and DAC, which have a completely new voltage gain stage topology (as well as no global feedback), show any measurable changes?

Merry Christmas!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 24 Dec 2011, 01:46 pm
What, no magic internal hookup wires?  From Shabango Shuntatatatatata, with anti electron strand hoping twists?  You mean it's all about electrical design and components!  Oy Vey, reality, what a concept!  AVA sonic bliss and perfection, still.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 24 Dec 2011, 02:17 pm
I see I generated a lively debate
Ok after 100hrs I can report I am about 80% there.  The raindrops are now clearly audible with the 400R but at a slightly reduced volume over what I am use to. 
I know Frank said burn in would not make a difference, but it did.  I even burn in used equipment before I listen, you just do not know how long the caps have been idle.
I think I can beef up the ribbon a bit at the xover. 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 24 Dec 2011, 02:29 pm
I do need the input impedance of the 400R Please
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 24 Dec 2011, 02:34 pm
 :scratch: Only 80% ? Are you saying if my AVA stuff is off for a week, I need to play it 100 hours before I listen to it?   :scratch: :scratch: :scratch: :scratch: :scratch:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 24 Dec 2011, 05:01 pm
Festuss please!  This thread is for users to report on what they hear, not for arguing about what they hear.

If pelliot says the treble improved to his hearing after a 100 hour burn in, that is what he hears.  There is absolutely no point to debating about what he says he hears.

I want a kind and interesting discource here, free of flames and fireworks.  It is altogether possible for extended run time to improve vacuum tube based equipment such as the Fet Valve 400R and 600R amps.  The small signal tubes do indeed need run time to settle down.  What an owner hears as this happens is what he hears.  When it comes to tube equipment the user may very well hear the equipment evolve into even better than out of the box musicality.

Best regards, and a wonderul Christmas and great New Year to all.

Frank Van Alstine

P.S.  The input impedance is 1 meg ohm, its a triode imput.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 26 Dec 2011, 08:35 am
Oh yeah, tubes do take a bit of time to settle down. So, apparently, do the rest of us.  :wink:

Ok time for my daily "effing AVA" moment. The Dhol Foundation's debut album has some percussion work that is meaty beaty big and bouncy. It has never failed to sound anything less than excellent to me. They can put on a bit of a show live, apparently, e.g.

http://www.youtube.com/watch?v=uNDPRHH5BUc

But now, with the 600R...

:o 8) :lol: :icon_lol: :thumb: :angel: :rotflmao: :inlove: :dunno: :eyebrows: :drool: :singing: :xmas: :hyper: :dance: :bounce: :rock: :kiss: :birthday: :wtf: :deadhorse:

 :bowdown: :notworthy: :bowdown: :notworthy: :bowdown: :notworthy:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 26 Dec 2011, 03:27 pm
Are yuu saying that you really like your Fet Valve 600R amp?

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 1 Jan 2012, 07:57 am
Are yuu saying that you really like your Fet Valve 600R amp?

Frank

Hi Frank,

I'm wondering if this is also a matter of toning down harmonic frequencies that would have ordinarily cause the perception of brightness? When Hugh Dean and his amps were on the circle, that was one thing he strived to deal with. And you know, his newer amps are right up there in sound quality with the best of them. Not to detract from this thread, I was just also thinking about the fact that even though we humans can't hear above 15K or 20K if we're lucky, the harmonics associated with the wide band amps do make a difference. So have you ever plotted the harmonic freqs? This stuff will be even more true as the devices get faster.

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 1 Jan 2012, 08:03 am
Are yuu saying that you really like your Fet Valve 600R amp?

Frank
Almost forgot, now, is there anything more you can do to improve your SolidState stuff? I know this is not on topic, but i didn't see anywhere else to ask this?

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 4 Jan 2012, 04:41 am
Most here have just upgraded from another AVA amp, except for the comparison to the A21 there haven't been any mention of how the "R" series compare to other brands.  Can you say what league the AVA amps are in?  I haven't heard any AVA and wondered are they toe to toe with the likes of Levinson.

Also, as a potential customer some specs on the website would be appreciated, or additional specs.  For instance, the input impedance should have been posted to where one wouldn't have to ask.  I didn't see mention of features either like XLR/RCA other connections 12v trigger etc.  Another post mentioned no global feedback, if that's true it should be mentioned, I find that a nice attribute.  If a person is deciding on whether to bring an amp in for evaluation you want to get a feel for if it will meet your needs or wants.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 4 Jan 2012, 03:03 pm
Even though I decided not to keep My 400R, I think it is a very good amp.  I compared it to a pair of dbSystems monoblocks, a ClassD Audio digital amp and the TAD-60 (KT88).  The 400R certainly bested the dbSystems monoblocks and the ClassD Audio by a wide margin.  It was the 60watt/ch KT88 Chinese amp that I liked better.  To be completely fair we tested three preamps, and the sound was different as was expected with the different preamps.
Out of the group of friends that spent many hours of listening, one preferred the 400R no mater what preamp we used.
There were some that felt that the differences between the 400R and the TAD-60 were very slight and a toss up, and one preferred the TAD-60 over the 400R(me), no matter what preamp we used.
Now for complete disclosure, the best sound(for me) was with the TAD-60 in triode mode, but in this mode the TAD-60 could not play as loud as the 400R.  In triode mode the amp can only put out about 40watts.  So for careful listening at reasonable levels(less that 85db) its the triode mode for me, and if I want to rock out a simple switch and I can drive the Maggy's to the mylar slapping point which is around 95-100dbs 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 4 Jan 2012, 07:43 pm
The tube vs. hybrid comparison is pretty interesting. I was so completely convinced that I preferred the U70 to the 550 that it took a good long hot summer to give the 550 a long listen. When I put the U70 back in, lo and behold, I had changed my preference.  :scratch:

The way I see it, different is not always better, but it can be fun anyway.  8)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 5 Jan 2012, 01:45 am
Even though I decided not to keep My 400R, I think it is a very good amp.  I compared it to a pair of dbSystems monoblocks, a ClassD Audio digital amp and the TAD-60 (KT88).  The 400R certainly bested the dbSystems monoblocks and the ClassD Audio by a wide margin.  It was the 60watt/ch KT88 Chinese amp that I liked better.

pelliott, I'm glad you were able to come to a satisfactory conclusion. I am a bit suprised about running the Maggies with a low power triode. I thought the Maggies were a much tougher load to drive.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rcag_ils on 5 Jan 2012, 03:17 am
I drove my maggie with a 20 w/ch triode, and a 40 w/ch ultralinear push/pull and couldn't get enough volume out of them.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 5 Jan 2012, 03:28 pm
"In our big hybrid power amplifiers, I can kind of give you a time line of the things that have been improved over the years.  Each made easily audible improvements in musicality and reduction of grain and listening fatigue, but almost none can be observed with our test equipment."

Wow,
  Frank set out a nice explanation of the improvements to the FetValve hybrid amps over time.  Can anyone put the names & dates on the models as they changed?  I get so confused by the fetvalve amp name progression....  :cry:

Murf
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 5 Jan 2012, 07:03 pm
I am not going to go off topic here, other to say that at the factory Maggy demo's the 1.7, 3.7 with a 40 watt tube amp
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 6 Jan 2012, 04:01 pm
The Fet Valve 400R amp was received back yesterday in brand new condition and bench and system tests say it is just fine.

I really can't believe that a 60 watt tube amp would offer anywhere near the dynamics and transparency of a  Fet Valve 400R running power hungry Magnapans.  Oh well, we certainly are not going to please everyone.

In any event, we now have a lovely new 400R ready for a new owner and available right now.  Inasmuch as it is very slightly used, including a one hundred hour burn in on white noise, it is available at a $200 discount.  $2349 plus $45 shipping.

This unit has our standard black faceplate and an IEC AC power socket.

Call us at 651-330-9871 to order.

Best regards,

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 6 Jan 2012, 04:27 pm
The 400R amp has sold.

That took all of ten minutes!   :)

Regards,

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 6 Jan 2012, 06:19 pm
Cool!!! Yeah really, more watts is more control!   Bizarre. And it's IMPOSSIBLE that a 60W all tube, sounds better, I would put money that it sounds bloated and dull.  WATTS in AVA form, pristine, clear dynamic. More watts ain't louder, it's CONTROL, more current available, etc.  Been low power, and it stinks.  Watts in AVA form are LIVE.  60W ain't doing anything close what a much higher powered AVA is gonna do.  Especially AVA hybrid, best of both.  sonic Bliss.  He didn't mention having to "burn in" Chinaman.......sum ting wong.  The specs on the Chinaman, look ABYSMAL, I think perhaps this person wants very colored, dull, non lifelike sound.  It just doesn't make sense. But it's great someone  got it, and is gonna REALLY enjoy it!  AVA, sonic BLISS priced for mortals.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 6 Jan 2012, 06:39 pm
Be kind, remember "better" is in the ear of the beholder.  Not saying each is comparable but keep in mind Frank's valve amp is rated at 35 watts and he says it keeps pace with a 100 watt solid state amp.   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: jtwrace on 6 Jan 2012, 06:42 pm
It's pretty sad that a man gives his opinion and now he gets bashed for it.  The 30 trial is there for just what this buyer did.  Tried and it didn't meet HIS expectations

Why all the fuss over it?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 6 Jan 2012, 07:23 pm
I agree.  This thread is open to user's opinions, and they are for sure their opinions, for better or for worse.

We can't assume that the user did not hear what he says he hears.  We might wonder about it, but can't deny it.  No point browbeating about it.

Calm down Festuss, the guy liked his 60W tube amp better, we can't change that.  One of his comments makes me wonder about the rest of his system though.  He claims that several listeners could hear no difference at all between the 400R and the tube amp.  I can only think this would be possible if the front end of his system was not very transparent at all.

I could also mention here that I have slowly come to realize that a really good preamp will help minimize major sonic differences between amplifiers.  A power amp has two musical problems in general, one is its own built in distortion.  The other is how it behaves on distortion from the source.  A great amp will not take the source distortion and distort it even more.  A lesser amp will add not only its own distortion, but will also further distort distortion from the source, making things worse.  If the source has minimal distortion, life is made a whole lot easier for the ho hum amplifier.  Differences should still be obvious on well recorded and dynamic source material, but a really good preamp is kind to the amps attached afterwords.  How this applies to pelliot's case I have no clue.  He just did not have the results I would have expected when the 400R went into his system.

Regards,

Frank Van Alstine

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 6 Jan 2012, 08:34 pm
It's not like he hated it either, he just liked something else better.

At the moment I keep going back and forth between the JBLs and the Tannoys. I think absolutes are hard to come by, and then you shoot past 'em because they're fixed and we're flabby squishy things. :bounce:

So in the end one user got a free audition at a great amp (and, I have to assume, kept another great amp) and another user got a great amp for a nice price break. Sounds like a good deal all around. Well, except that Frank lost a couple of Franklins, but he seems to be able to handle that petit contretemp.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 6 Jan 2012, 09:25 pm
You guys still do not know how to read very well,  We used three different preamps. The speakers were maggy iiia's The sound did not change that much between the preamps.
I also said the 400R was a very good amp
Frank you should have received ti back by now so I am waiting for the refund
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 6 Jan 2012, 09:28 pm
Hi Paul,

Your purchase price was credited back to your CC account today.

Thanks for your comments.  I wonder what DAC you were using, or was it all vinyl when using the FV400R?

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 7 Jan 2012, 10:39 am
 :D  Absolute sound gave 400R Fet Valve  BEST BARGAIN amplifier, and a giant killer comment!  In this months issue.   Also best bargain for best sound, looks like the 400R and 600R Fet valve is yet another lineup  in the continuing AVA sonic bliss, for mortals.  45 years and still going strong.  Once you have AVA the other stuff just looks so grossly over priced and dumb.  Wonder which province in China his better sounding amp came from, cus they have different sounding ckts depending on the contamination in the water. When the boards are washed off during mfg, it affects the sound. This episode just baffles me.  Sum ting Wong.   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rcag_ils on 7 Jan 2012, 10:54 pm
Quote
Especially AVA hybrid, best of both.  sonic Bliss.  He didn't mention having to "burn in" Chinaman.......sum ting wong.  The specs on the Chinaman, look ABYSMAL, I think perhaps this person wants very colored, dull, non lifelike sound.  It just doesn't make sense.

I don't see how Frank could allow this kind of racist ranting in his thread, Festuss sounded like a sorry white ass living in a trailer park.

Pelliot likes what he likes and he has the right to do so. Festuss, whatever color fetus you are, knock that shit off.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 9 Jan 2012, 01:29 pm
I am still amazed that you are looking for fault with either me or my system, as for the reason why I rejected the 400R.
I never said it was anything wrong with the amp, only that it was not a big enough improvement over what I have to justify over $2500 expense.
(http://www.audiocircle.com/image.php?id=56119)
(http://www.audiocircle.com/image.php?id=56120)
My sources for Vinyl is a Sota Star Sapphire with Alphson 100HRS tonearm with shelter 501 series II cartridge
step-up is either Lundalh transformers or Vendetta Research SC1
For digital is a Sony 9000 for transport only, or Logitech Touch/ wintel music server no wireless connection
DAC is TwistedPear Buffalo II(Trident regulators)/Lagato3output with separate digital/analog powersupplies The buffalo uses the ESS Sabre 32bit chip.
Preamps are either the Transendent Sound Grounded grid or the Dodd Buffer
Power amp is the TAD-60 with KT88's in triode mode
Electronic Xover is Marchand XM9/Basis Bass Correction Equalizer set at 40hz.
I am only using the low pass filter for the Subs. The Maggy's are running full range
Subs are Janis One's powered by a 150 watt chip amp with over 200000 mfs in powersupply
Subs are flat from 40hs to below 20hz
Subs were not used during the evaluation of the 400R   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 9 Jan 2012, 03:19 pm
Nice stuff. :green: But does that tube amp run so hot it needs a chimney exhaust?  WOW. Looks like you also have several better sounding blocks of wood and metal things under electronic equipment....what does that actually do? Especially one in the center of a chassis which should be supported at the corners, so as to not flex and stress stuff inside, no? 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 9 Jan 2012, 03:56 pm
I am still amazed that you are looking for fault with either me or my system, as for the reason why I rejected the 400R.
I never said it was anything wrong with the amp, only that it was not a big enough improvement over what I have to justify over $2500 expense.
(http://www.audiocircle.com/image.php?id=56119)
(http://www.audiocircle.com/image.php?id=56120)
My sources for Vinyl is a Sota Star Sapphire with Alphson 100HRS tonearm with shelter 501 series II cartridge
step-up is either Lundalh transformers or Vendetta Research SC1
For digital is a Sony 9000 for transport only, or Logitech Touch/ wintel music server no wireless connection
DAC is TwistedPear Buffalo II(Trident regulators)/Lagato3output with separate digital/analog powersupplies The buffalo uses the ESS Sabre 32bit chip.
Preamps are either the Transendent Sound Grounded grid or the Dodd Buffer
Power amp is the TAD-60 with KT88's in triode mode
Electronic Xover is Marchand XM9/Basis Bass Correction Equalizer set at 40hz.
I am only using the low pass filter for the Subs. The Maggy's are running full range
Subs are Janis One's powered by a 150 watt chip amp with over 200000 mfs in powersupply
Subs are flat from 40hs to below 20hz
Subs were not used during the evaluation of the 400R

Hi Paul,

Well, the only fault I can find is the GG Preamp. We both know it's just ok, nothing really astonishing about its sound qualities. So Frank might have a point here with referencing to the preamp. It's not that revealing. It is however revealing enough to shed some light on how good two pieces of equipment are. But!... you do have the right to your opinion, and I can honestly see that under certain conditions running Maggies at low power, which would mean low volume, could give you possibilities of slightly better detail ETC. Everyone who is squawking how this can't be or that can't be, ... well like Frank said, and again, he is to be commended for being a gentleman about it. "it's his opinion." The rest of you naysayers could take an example from Frank.

Now if paul had stated that the amp was really bad and he didn't like it at all, then perhaps some of the criticism that has been leveled at him might have been justified.

Personally, if I ever get my hands on a lot of money, and if my ears improve, I would probably just buy Frank's stuff. It works, it's proven what can be done with good stuff, and ... well, it just plain works. Then put some good speakers and a good source to them, and be done with the ratrace for many years.

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 9 Jan 2012, 04:40 pm
As I stated numerous times before we used THREE different PREAMPS during the evaluation. My GG, the Dodd Buffer and a Audible Illusions L-2.
I Liked the AI best for the warmth but the GG was better for detail the Dodd was ok.  Anyway the TAD-60 in triode mode bested the 400R no matter which preamp I was listening too except for bass strength.  When the TAD-60 was in pentode mode there was very little difference in the bass.
I know that most of your(RAY) information is based on what you have read on these forums, all hearsay.  You do not own a GG, or have heard any of this stuff we are talking about.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 9 Jan 2012, 05:23 pm

I know that most of your(RAY) information is based on what you have read on these forums, all hearsay.  You do not own a GG, or have heard any of this stuff we are talking about.

Oooh, Brother, let's clear some stuff up right now paul. Before you start attacking me, it was you! and a few others whose ears I trust have played with the GG, that told me that it wasn't that good of a preamp. It's ok for the $500 pricetag he's charging and that's all. And yes, I have heard a home brew version, and agreed when I told you about my experiences with it, it's ok. For the record, this is one reason why I haven't really tried to get one. I was only stating that if there was a weak link in your stuff that it would have to be the GG preamp, that's all. i'm sorry Frank to have hijacked your thread here. I did also note that while it's an ok piece, that it was still good enough to show some differences in equipment. i certainly wasn't in anyway out to bash your use of the GG Pre, but was pointing out that like Frank had suggested that a  preamp could be a weak link. Nothing more nothing less. As to what I have heard or not heard, I also defended your position, and this is what I get? i'll betcha Paul there are a lot of peiple like myself on the circle who don't have the availability of hearing a lot of the stuff that is on the various circles. So others like myself, ... we have to take the word of others. Although very opinionated, and I have yet to meet an audio designer of audio gear that isn't, he produces some really good gear. His opinions that I have trouble with, I just take in stride. There are those out there who do not like to hear possible negativisms about there brand of gear. Frank to his credit was ok shocked at your returning it, but at the same time was seemingly really genuinly interested in why you heard what you heard. I don't think he in anyway was bashing your stuff at all. It was some other folks on this circle who gave you hell, and by the way, I'm not one of them. Cool your jets Man.  If anything, I was out to defend what you heard, and that's ok.

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 9 Jan 2012, 08:13 pm
 :o I think ya need to go with the 600R.  More watts, better control.   And better yet is with the phase inverter, have TWO,  and run em in mono and really get those speakers going.  Probably are not getting everything out of this setup, with such low power.   More watts opens up good speakers.  LIVE is what ya want. Not louder, just better, and clarity and control, bass with DETAIL is impressive when done right.  Sloppy mud is not lifelike.  Well unless ya hang out at Stone Pony in Asbury Park N.J., which has the worst sound of any place I have ever been, BOOM BOOM BOOM.  Now back to the 400R.   
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: pelliott321 on 10 Jan 2012, 01:16 pm
I just do not get these comments about what I heard on my system, as if I am, or my system is at fault.  I am not one of these idiots that feel that just because I own it, its the best. I am the only critic I will listen to other than the other people in the room listening with me.  That why I invited friends over to hear the 400R and compare it with other amps and using different pres.  That's my reality check not what a bunch of forum trolls have to say..
This all started because Frank asked for opinions.  It is his problem that he never expected that some one would actually compare and comment in a slightly negative way.  I never said that it was a bad amp, I even praised it on some aspects.
If I had kept that amp it would have been the most expensive component I have ever purchased. $2500 is a lot of money to me and it would have to been a game changer for me to keep it, and it was not.
I posted the pics and description of my system because Frank questioned what my front end was.
This is my last word on this subject here.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: kip_ on 10 Jan 2012, 01:58 pm
:o I think ya need to go with the 600R.  More watts, better control.   And better yet is with the phase inverter, have TWO,  and run em in mono and really get those speakers going.  Probably are not getting everything out of this setup, with such low power.   More watts opens up good speakers.  LIVE is what ya want. Not louder, just better, and clarity and control, bass with DETAIL is impressive when done right.  Sloppy mud is not lifelike.  Well unless ya hang out at Stone Pony in Asbury Park N.J., which has the worst sound of any place I have ever been, BOOM BOOM BOOM.  Now back to the 400R.
Festuss, you need to get a life and actually READ and comprehend someone else's post for once. The AVA amp, no matter how great, was NOT his thing. Have you ever even heard any non AVA amplifiers or are you merely drinking the kool-aid? No disrespect intended to the brand, but you're being a jerk.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 10 Jan 2012, 03:01 pm
I do wish that my supporters, no mater how enthusiastic, would heed to my desires more closely. Moderation please!

"Over the top" support often turns many more people off about AVA than helps us. Festuss has a very unusual system with about 6000 watts of AVA power amps running it.  It has been described by the editor of Stereophile in glowing terms (although he failed to mention that the amps used were AVA designs).  Perhaps Festuss is right that without that much power we are all missing a lot.  However, I do wish he would mellow out in disparaging lesser systems.  I only have 300 watts a channel myself.   :o

I would hate to have to kill this thread because of flame wars.  :cry:

Regards,

Frank Van Alstine
Title: Children, children....
Post by: murf on 10 Jan 2012, 04:04 pm
No fighting, please!

Paul said:
"Out of the group of friends that spent many hours of listening, one preferred the 400R no mater what preamp we used.
There were some that felt that the differences between the 400R and the TAD-60 were very slight and a toss up, and one preferred the TAD-60 over the 400R(me), no matter what preamp we used."

This seems like a very even evaluation, and I sense no hidden agenda.  One person liked the AVA best no matter what, Paul ditto for the TAD, the others in between.  What's the prob?  It's not like the TAD-60 isn't well regarded (for a low powered amp).
My wife went to school on a voice scholarship.   She still sings in amatuer groups, and has great ears!  My ears had a scuba mishap many years ago, although they check out fine now.  Somehow, she is happy listening to equipment that I am not.  Is the difference in our preferences, brains, or ears?
Some like volume, some like big bass, some sparkling treble, etc.  Some people like the 'sharpness' of BMWs, some like 'smoothness' of Audis.  What's wrong with those Audi drivers (I drive a BMW)?   :green:
I commend Paul for giving his somewhat non-welcome opinion here.  It's fine to question him about his conclusions, but they are valid for him, and thus are what this thread asked for (to Franks credit).  In my innernet ramblings, I stumbled across someone else who didn't think his Maggies were a good match for his AVA amp.  I think my AVA amp is tits, maybe because my speakers have big 10" woofers like Franks favorite Salks do.  These differing opinions are standard audiophile fare.  Someone will get down on equipment no matter what the price or how 'good'.  Some will trumpet a low priced unit as a giant killer. We can only hope to know why by listening to what these people say, whether we agree with them or not. 
In summary, I think Paul should understand group dynamics a bit better & not judge by the worst examples, and some in this group should thank him for his contribution rather than question his ability to evaluate and the validity of his opinion. 
Sure would like to see that 'Chinaman' post deleted.  It isn't cute.  I only let close friends call me a 'mick', then I punch them!  :deadhorse:

Murf
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: mark funk on 10 Jan 2012, 04:13 pm
This is not the first time! Life well not come to an end(that well be in December :lol:) because some one did not pick Frank's amp! Last year a guy from work came by to hear my set before he redid his set. Well, after that he went out and got a Rotel something amp and preamp and a Raga CD player with a $1,400 new pair of B&W something speakers :o. 

It's kinda of sad when I am afraid to go out side of this circle because I am an AVA supporter! A lot of times we treat people kinda bad  :oops:.
What I tell the guys at work,

                                                          Take it easy!


                                                                                    :smoke: 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 10 Jan 2012, 04:28 pm
HEADS UP TO ALL!  We shipped the first batch of new Fet Valve equipment today with the new SILVER faceplates.

There is more to it than just the faceplates:  New power switches, new blue LEDs, hidden faceplate mounting hardware, and electronic switching control for the power amps, along with lots of mechanical design and graphic artist time.

We could now actually do a remote turn on and turn off trigger for the Fet Valve amps if someone would be so kind to inform us of what the industry standard hardware and voltage is for this function.

Its taken almost 3 months to get the faceplates done properly for us.  We are ready for more orders now.  We have all learned to build them efficiently and totally bug free.

By the way, two different writers for THE ABSOLUTE sound gave us "best bargain at the show" mentions for the new Fet Valve products at the recent Rocky Mountain Audio Fest.

Best regards,

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 10 Jan 2012, 06:07 pm
Hi Frank & Folks,

  I'll be shipping my 350+ this afternoon for the big 400R upgrade (who needs more power in a brklyn apt when it has such finesse, is so suave & dubonet?).  The only thing I don't like about the looks of my old black-faceplate is the power switch.   Can I go to Autozone or Pepboys & get a cool blue switch (it would then match my pre, transport & dac lite color)?  The switches look very similar....  :nono: :shake::scratch::wtf: :oops:


On another subject, I see Frank has the new silver faceplate amp shipping, so I would like to ask you all to NOT order until my upgrade can get to Frank & be in line ahead of you.  I REALLY hate listening to my lesser amp for long (B&K st-140; who designed that one!?), and then desperation sets in, and I'll have to call Frank & ask where my new amp is, and then Frank will yell at me, and....I'm sure you understand!   :thumb:

Murf
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 10 Jan 2012, 06:45 pm
Murf, your "cool blue switch" probably will work for about three or four turn-on cycles before it fries.

The standard "ho hum red" power switch we use is the ONLY decent looking power switch with an 80 amp inrush current rating we can find.  This is necessary to keep the switch alive during the very momentary time at turn-on as very high current flows then, forming up the electromagnetic field in the power transformer and providing peak charging current into the big power supply capacitors.  Our VERY heavy duty switch along with inrush current limiters, keeps the switch alive long term.  A standard 15 amp rated switch just won't hold up very long under this load.

On the new Fet Valve 400R and 600R amps with the silver faceplates, we had to deal with this differently.  The nice little pushbutton switch we chose for both the amps and the preamp and DAC all have a max 8 amp rating.  They are fine for the preamp and DAC, but would fry instantly in the power amp.  So we designed and installed a triac controlled turn on and turn off circuit.  The switch only triggers the triac on or off and supplies nearly no current at all.  The very rugged triac with a 200 amp rating and an 800V rating actually controls the current to the circuits, not the switch itself.

I suppose, if you wanted to pay extra and supply the switch (and it would have to be a perfect "snap in" fit into the black faceplate), we could use a different colored switch, all other things being equal, (but often they are not) and use it with the triac control circuit.

Regards,

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 10 Jan 2012, 07:04 pm
Um, I'm fine wit da red.

A simple 'no' would suffice.  I'm always amazed how Frank will indulge us & our (or rather, my) stupid questions & let us peek inside his creations.  Sorry to take your time Frank, but the new amps do look great (but my upgrade to a 400R will sound just as good!).

Murf    :kiss: :kiss:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 13 Jan 2012, 03:56 pm
Quick mini-review update.

Bells...

A couple of days ago I put on von Karajan interpreting Also Sprach Zarathustra (the 1984 recording). This one is rather scary loud at the start so I listen to a few seconds at the start of the 2nd movement to set the volume knob, then I buckle down and come back to the 1st movement and for a proper listening. If it's loud, it's loud, etc. So naturally I was enjoying the opening trumpet sunrise theme, with the very, very loud and well controlled double bass and organ for support, and the rest of the piece flowed along very well. Then I remembered I had to web about a bit and multitasked while the rest of the piece played along. Thus somewhat distracted, I was enjoying the piece when the last movement was reached and there was a hammerblow to the bells that just astonished me. I almost dropped my keyboard to the floor, I could have sworn the bell was right in the room.

Then last night, I played Dark Side of the Moon. No prize for guessing which song produced the same astonishment at the sound of bells, clocks, alarms et. al. It was like I had gadgets all over the room going off on their own, like something out of a Twilight Zone episode.

This morning it's Kula Shaker's "Peasants, Pigs and Astronauts" blending British rock and Indian music, acoustic and electronic, which presents all sorts of lovely opportunities for an amp to show what it can do. On "Namdi nanda-nandana" there is an intro with a water stream, birds, a woman reciting and you might as well be eavesdropping in some Indian forest at dawn when Crispian Mills comes in and chants the title, then some electronics hop on the background and the woman becomes a soprano and, well, all of this happens with such clean and musical separation that you can hear what everybody is doing without any effort at all, and before you know it the prescribed several minutes of silence come in because, as it turns out, the beautiful song is merely an introduction for the greater beauty that is to be provided by the listener's meditation.

The thing of it is, I had all three albums pretty well memorized. There's nothing new here. Same old same old. So, well, I'm hearing all kinds of things anew and, really, all of them musical? Simultaneously relaxed and intense? Nothing bad, all better? Huh? Some stereo rags claim that good equipment can make albums sound worse, and thankfully I am confirming that that was just a bunch of BS?!

One last quick mention--the Moody Blues in the 60's put out some fantastic albums but the mix might not have always been the best. To some extent you had to guess, the ear and the mind interpolating to flesh out the correctness of their musical idea. Well now I found myself doing so much less interpolation, so much more relaxed listening that in the end I was ready to say that maybe the recordings were not so bad after all.

It's been some weeks already since I've put this 600R in the chain and I continue to shake my head and smile at unexpected moments when I listen to it. I know this music, sometimes I can even read the musical score so I more or less know what it's supposed to sound like, and yet, there still remains the last layer of pleasant surprise. Undoubtedly the steadfast attack on distortion and the silly-fast slew rate are worth the effort. I feel like when I hike into the Sierra Nevada and drink from a stream--it's mostly the same two atoms of hydrogen and one of oxygen but the tiny additional differences create a sensual experience that lifts your spirits in ways that are not as materialistic as they might seem.

For the n'th time, congrats Frank and crew...
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 14 Jan 2012, 05:37 am
I must confess I am the one who bought the 400r and here are my impressions.  I am driving a set of Revel Performa F52's with Conrad Johnson MV-60's mono and a CT-6 pre.  I put the 400r in place of the MV-60's.  I was looking for more power while trying to find something to maintain the musicality of the CJ.  Right off I was impressed by the 400r, I was hoping it would be good but I never expected it to be this good.  The 400r's strength in my system was the midrange and musicality.  I did find out quickly that at least the FET Valve amps are particular about cables.  I noticed after turning off the music on the first listen I had a serious hum issue, through Frank's help and tracing the problem I discovered it was my cables, Siltech MXT Pro New Yorker.  These are directional and apparently not shielded on one end which turned it into an antenna.  Don't rule out all directional cables though a set of Transparent worked fine.  Sorry Frank, the generic sounded like crap.    As treble seems to be a point of discussion here I personally thought it was fine to me but did pick up that the very upper high frequencies don't seem to be as vivid as the lower high end.  For example, a High Hat seems to be more pronounce than a cymbal crash.  There are a couple pronounce cymbals on Eric Clapton's Old Frisco and a Chicago song I'm aware of and neither were as pronounced as I'm used to. I'd describe the high end is very smooth and musical.  A friend always tells me listen for the midrange, if it's right all else comes after.  If nothing else Frank has the midrange correct, not only did it keep the melody, groove and soul of the music it exposed all the details within.  Here's where my experience differs a bit.  I found the bass on some recordings looser than I expected, this isn't all bad compared to amps like Krell which have an iron grip, it depends on what you like.  Also, on some recordings I got a bit of congestion in the very low frequencies.  My suspicions is maybe the CJ preamp and 400r doesn't have the best synergy.  It's odd though because the CT-6  using 6922's has a very nimble bass response, in fact, it's not stereotypical tube bass response at all.  I also wonder if the preamp has the output voltage needed or perhaps a slight impedance mismatch.  I do plan to try the FET preamp soon.  This should tell me something and I will be back.  Don't get me wrong, even with what I mentioned the bass was good and on other recordings there was control that I hadn't heard before.  The fact the bass varies on recordings, and sometimes song to song on the same album shows the 400r isn't artificially adding anything.  With the 400r in my system I found myself just sitting and enjoying what it does, it gives music a certain coherency and you experience layers of detail.  On Christian McBride's stand up bass you could just feel the bow pulling across the strings.  Vocals were more intelligible.  On several recordings there were just more details in the music exposed.  I found the 400r musically satisfying and a new home.  I did give Frank some grief though about putting the hook ups at the bottom of the amp under where the heat sync sticks out.  Connecting from the front of the amp was a bear.  I found the 400r an incredible value.  I would urge any one who is interested in spending their money wisely to try Audio by Van Alstine before raiding the kids college fund to purchase that mega dollar piece that wow'd you in a showroom. 

I feel it's important to point out I have owned amps by Krell, Arcam, had ARC in on audition, still have a Bryston, Linn and of course Conrad Johnson, listened to amps like Levinson and Boulder, so I feel I have some idea of good amplification.  I gave my honest experience with the 400r.  Our audio purchase is a subjective decision so no one can say a certain amp is the best in the world.  What I will tell you is the 400r will go in my rack in place of my current CJ monoblocks.  And, if good results an AVA preamp may soon follow.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Stercom on 14 Jan 2012, 10:51 am
Thanks Mr. Peabody. Honest and informative review. Let us know where you end-up regarding the preamp and cords. (Yes, AVA devotees, and Frank, I know your position on cords - please lets not let the comments to this review go off on that tangent again :D)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 14 Jan 2012, 02:02 pm
The comment on the cables was meant as an attempt at humor and not a slam.  I realize not all are in the aftermarket cable camp.  I for one have no problem in hearing different effects on my system from various brands of cables.  A lot of it has to do with resolution, which makes me think Frank's gear should not have a problem revealing these differences.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 14 Jan 2012, 05:16 pm
As treble seems to be a point of discussion here I personally thought it was fine to me but did pick up that the very upper high frequencies don't seem to be as vivid as the lower high end.  For example, a High Hat seems to be more pronounce than a cymbal crash.  There are a couple pronounce cymbals on Eric Clapton's Old Frisco and a Chicago song I'm aware of and neither were as pronounced as I'm used to. I'd describe the high end is very smooth and musical.

Mr P, thanks for expressing more clearly and succintly something along what I was trying to describe with my own review.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 16 Jan 2012, 12:09 am
Mr P, thanks for expressing more clearly and succintly

Hi, Again, I raise the question of possible harmonic removal. You two guys are the second peoples now that have raised this treble thing. It seems to me Frank that some further analysis needs to be done. I am in no way smamming your amps. With the lack of this particular distortion or harmonic presence, you are now hearing an amplifier that is free from that form of distortyion. something along what I was trying to describe with my own review.
Ray Bronk

P.S. For some reason, JAWS my Screen reader is not tracking this edit. So part of the previous poster is below my post. Siorry about that.

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 16 Jan 2012, 02:12 am
Well, I'm not sure what happened to my entire post but I will try this again.

Let me be clear, there is nothing wrong with the frequency response of the FET Valve amps, what I mentioned was merely an observation not a criticism or deficiency in any way.  Not all amps will react or respond the same.  Also, keep in mind the amps effect will be impacted by associated equipment and whether or not there is synergy.  I don't know of any one amp that is unanimously liked.

I also doubt if the amount of treble one hears is solely do to distortion or if at all.  Krell has a prominent high end, to match the rest of it's response, and I can assure you it's not due to distortion.

I was listening to a Reference recording today called Pipe & Organ, the 400r was really shining.  The pipe organ was deep and controlled, brass had what I can only call a growl like it's supposed to, kettle drums had transient response with no lag or distortion, things like triangles, bells and cymbals sounded through clear with a sparkle and never piercing or brash.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 16 Jan 2012, 02:25 am
Ray, you just never know, a fellow Jaws user here. :)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 16 Jan 2012, 02:30 am
Let me be clear, there is nothing wrong with the frequency response of the FET Valve amps, what I mentioned was merely an observation not a criticism or deficiency in any way.  Not all amps will react or respond the same.  Also, keep in mind the amps effect will be impacted by associated equipment and whether or not there is synergy.  I don't know of any one amp that is unanimously liked.

What Mr P said. It's hard to provide observations without it sounding like criticism to someone. I think that's part of the problem with text only discussion.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 16 Jan 2012, 03:58 am
What Mr P said. It's hard to provide observations without it sounding like criticism to someone. I think that's part of the problem with text only discussion.

I can understand that. Actually, it's fairly conceivable that by removing this one form of distortion you might be actually hearing what was really recorded. To bad the CJ was showing a bit of conjestion. I am in no way criticizing Frank's amp at all. This little anomoly may not be one at all. Frank's amps are getting up in the pricetag of other good amps. It would be interesting to have a comparison of this amp versus other stuff in the price range. But that's a different subject for a different thread. So Frank have you looked at this amp to see if there are any suppressed harmonics or distortion figures that normally you'd see on any amp that with yours is gone??

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 16 Jan 2012, 11:38 pm
I think Frank should buy one of those $10k amps and write his comparison to the 400R. What could possibly go wrong? :peek: :peek: :peek:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 17 Jan 2012, 12:32 am
I think Frank should buy one of those $10k amps and write his comparison to the 400R. What could possibly go wrong? :peek: :peek: :peek:

Well, he might have trouble selling it, since his 400R and 600R might either be as good or beat it.

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: WGH on 17 Jan 2012, 12:55 am
Frank's amps are getting up in the pricetag of other good amps. It would be interesting to have a comparison of this amp versus other stuff in the price range.

Well, that just might happen:


We are now building a new Fet Valve 600R for The Absolute Sound.

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 17 Jan 2012, 01:37 am
Awesome. Given the typical review time and lead time for publishing, that probably means it'll be late spring / early summer before we see it in print.

Frank, do you know yet who's going to revew it? Not sure if Sue Kraft writes for them anymore. Frankly I'd like to see it go to one of the heavyweights (nothing against Sue).
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 17 Jan 2012, 05:05 pm
Ah, Ray, your loyal, and, a sense of humor, what a guy.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 17 Jan 2012, 09:19 pm
After more listening to the 400r I have a couple more comments, I've come to the conclusion that the bass issue must have been in the recording and possibly masked by lack of detail or control, I played some modern R&B like Vivian Green and the bass was very good, I could easily hear bass guitar from the kick drum and when synthetic low end bass was interjected the 400r controlled it very well while it played deep with no distortion and if any one has the first Paula Cole album that first track goes subterranian and the 400r gave it one of the best renderings I believe I've heard. 

So next I had to get nasty and play some Blues, not only was the bass good on Joe Bonomassa's Blues Deluxe there was a blistering acoustic guitar track which played through the 400r the best I've ever heard, it's like I've heard it before but compared to the 400r the notes were blurred, through the 400r I was able to depict all the notes, and Joe smokes on this track.  Then some SRV and even Bob Seger Live Bullet, I've determined the 400r sets the benchmark on "Boogie Factor".  When listening to drums the treble response seems extremely good, cymbals, high hat etc.  I also get a sense of vocals being more intelligible.  Oh, and I also listened to some CSN&Y which was very good, I could here each individual voice in the harmonies, and the overall timing was more precise.  I'm liking the 400r more and more as we spend time together.

I played some Barber, Vanessa Williams, Monk, Christian McBride, Vivaldi etc. but sometimes you have to boogie. :)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 18 Jan 2012, 04:28 am
Mr P, in the brief time that I had the 600R for review I found the spacing between instruments exceptional.  It made older compressed recordings sound airy.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: slippers-on on 18 Jan 2012, 03:29 pm
After more listening to the 400r I have a couple more comments, I've come to the conclusion that the bass issue must have been in the recording and possibly masked by lack of detail or control, I played some modern R&B like Vivian Green and the bass was very good, I could easily hear bass guitar from the kick drum and when synthetic low end bass was interjected the 400r controlled it very well while it played deep with no distortion and if any one has the first Paula Cole album that first track goes subterranian and the 400r gave it one of the best renderings I believe I've heard. 

So next I had to get nasty and play some Blues, not only was the bass good on Joe Bonomassa's Blues Deluxe there was a blistering acoustic guitar track which played through the 400r the best I've ever heard, it's like I've heard it before but compared to the 400r the notes were blurred, through the 400r I was able to depict all the notes, and Joe smokes on this track.  Then some SRV and even Bob Seger Live Bullet, I've determined the 400r sets the benchmark on "Boogie Factor".  When listening to drums the treble response seems extremely good, cymbals, high hat etc.  I also get a sense of vocals being more intelligible.  Oh, and I also listened to some CSN&Y which was very good, I could here each individual voice in the harmonies, and the overall timing was more precise.  I'm liking the 400r more and more as we spend time together.

I played some Barber, Vanessa Williams, Monk, Christian McBride, Vivaldi etc. but sometimes you have to boogie. :)


Dang Peabody...im tickled pink! First the Dyns...now this! I mean its like you've been hit in your head too the white meat and blood! I would have never thought you would have ever parted with Conrad Johnson....but from your readings the less expensive, and no bling AVA bested the expensive Conrad Johnson and bested it by a large margin! I cant wait to get to your place and take a listen. Who knows...there may be a AVA in my future.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 18 Jan 2012, 06:02 pm
I think Frank should buy one of those $10k amps and write his comparison to the 400R. What could possibly go wrong? :peek: :peek: :peek:

Th Absolute Sound is getting a sample shortly and promised a "whirl-wind" review, so it may be out in the next or two issues. I think that will say it all.

Wayner
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 18 Jan 2012, 11:58 pm
If TAS gives a glowing review I'm glad my orders are already in before AVA gets swamped.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: jtwrace on 19 Jan 2012, 12:34 am
If TAS gives a glowing review I'm glad my orders are already in before AVA gets swamped.
Well, good for you....everything gets a glowing review from TAS.   :roll:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: charmerci on 19 Jan 2012, 01:42 am
Well, good for you....everything gets a glowing review from TAS.   :roll:

I would imagine the process works something like this now. Due to advertising needs (i.e. income) the magazines either a) review components that have a good sound reputation or b) they do preliminary listening sessions before making a full review to save money.

By simply avoiding any probable negative reviews all together, companies continue to advertise.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rcag_ils on 19 Jan 2012, 02:37 am
I do think that magazines nowaday have a good idea what they would review well in advance, probably heard the eq. before they made the decision on which to review and to print on paper, they won't pull something off the shelf and give them a good/bad review, Gordon Holt at Stereophile did that back in the late 60's, gave eq a fair review, good or bad.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 19 Jan 2012, 12:57 pm
Well, good for you....everything gets a glowing review from TAS.   :roll:

I'm glad we have you here to keep things fair and balanced.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: martyo on 19 Jan 2012, 01:39 pm
I'm glad we have you here to keep things fair and balanced.

 :thumb:  Yep, and that's the perfect descriptive term to use Wayner. 8)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 19 Jan 2012, 09:25 pm
I just spoke with Frank and on Saturday I will picking up a 400R, FET Valve Preamp and FET Valve DAC to review.  I'm looking forward to it and will post my review on Tuesday.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 20 Jan 2012, 01:02 am
I'm jealous, I wish I lived closer so I could test drive some of that gear. :)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: rockadanny on 20 Jan 2012, 01:50 pm
Quote
I'm jealous, I wish I lived closer so I could test drive some of that gear.
+1  :thumb:
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: slippers-on on 20 Jan 2012, 02:40 pm
I just spoke with Frank and on Saturday I will picking up a 400R, FET Valve Preamp and FET Valve DAC to review.  I'm looking forward to it and will post my review on Tuesday.

Looking forward to it!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 20 Jan 2012, 02:49 pm
Well, good for you....everything gets a glowing review from TAS.   :roll:

Well, TAS did name the 600R (& the FetValve Pre?) "Greatest Bargain" or something similar at the latest RMAF, which isn't a judgement given to everything.  It is an honor which might induce some discriminating readers to send their amps in for the big upgrade!   8)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 21 Jan 2012, 03:42 pm
Back with a bit more observations, now I know why pro reviewers keep gear for months before writing the review, that, and the fact, they can. :)

What I've found and it's no indication this is others experience, the FET Valve seems to be more honest in the high end.  When I commented in an earlier post that I thought the very high end may not be as pronounced as lower high end turns out in my opinion to be recording dependent.  As a very recent example, and keep in mind I am not just a Jazz/Classical listener, on ZZ Top Deguello the first track, I Want To Thank You, the cymbal crashes are what I'd call faint but on I'm A Fool For Your Stockings, the cymbal crashes are right in there with the rest of the mix.  In the latter case, and when cymbals are given proper context, cymbal crashes have a proper place but never brash, very smooth delivery without masking or washing it out.  I've played several albums since hooking up the 400r which helped me make this determination.  In most instances, you can tell the instruments in the high frequency range vary as the rest of the recording.

Merely, my take on things and keep in mind systems vary as well peoples taste.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 21 Jan 2012, 05:10 pm
RE, My P's observations:
  The better my equipment gets, the more I notice how bad some recordings are.  This seems especially so on R&R CDs which were first put out as vinyl.  Very often it is the top end which is compromised.  So recently I was wondering if I should try to flavor my speakers to have more top treble. 
  But then yesterday I put on "Blues Breakers" with Mayall, Clapton, McVie, Almond, et al., & it had so much treble!  I don't think I'll mess with the speakers for a while....

Murf
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 21 Jan 2012, 05:10 pm
Mr. P, your observations mirrored mine.  I found the cymbal crashes to be very natural and life like.  My son who played in band felt the same way.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 22 Jan 2012, 03:59 am
Well I picked up the 400R, DAC and Preamp today.  I have all three hooked up and running and all I am going to say right now is that the music just sounds right! :D

Reviews of each piece in my current system and as a whole will be posted on Tuesday.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 25 Jan 2012, 11:15 pm
I added Larry's recent review of all three new Fet Valve units, DAC, preamp, and 400R amp here.

Frank

   

I had the opportunity to do an in home review of AVA's new 400R power amp, FET Valve Preamp and FET Valve DAC.  I am a current owner of AVA's Ultra II Preamp and Ultra II DAC which are hybrid designs as are his new designs.  I also use a Parasound A21 power amp and Magnepan QR 1.6 speakers.  I live in the same town and Mr. Van Alstine and was afforded the opportunity to review his new gear.

First off, the new gear has a new updated look.  Gone are the black face plates and rectangular red power buttons as well as the 2 prong wired power cord's.  The new gear comes with a high quality thick aluminum face plate with a push button on off switch and a blue LED power light.  The old power cord has been replaced by an IEC socket and cord. The new gear has a more up to date look without being flashy.

At first I was going to review all 3 components together but I decided to try each piece individually in my system and then as a whole.

I first placed the FET Valve (FV) DAC in my system and the first thing that my budding audiophile 20yr old son and I noticed was how much smoother and liquid the new DAC sounded.  The sound stage was wider and there was more transparency and space between instruments.  In addition, bass was much deeper and better controlled. On Boxer Rebellion's "The Cold Still" the bass on the first song "No Harm" was thunderus.  Bass also had great thump to it.  I did not think that my 1.6's were able to produce such thunderus bass and thump.  My only criticism about the DAC when paired with my older AVA preamp is that it seemed slightly less crisp and snappy if you will for lack of a better term.  With my older DAC you could readily make out the pluck of the fingers coming of the strings, with piano you are able to hear the plinck of the keys and drums seemed a bit more snap. I am not saying that you could not hear it with the new DAC but it just was not as prominent.  It just seemed to have a little more sparkle and detail. However the new DAC was more listenable with no fatigue or sibilance, something that I can't say about my Ultra II DAC.

Next I paired the new FV Preamp with my older DAC.  I was pleasantly surprised to find that the new preamp was a marked improvement over the Ultra II preamp.  Bass was deeper and better controlled.  The sound was more detailed and smoother.  The music was more musical, vocals were more natural and there was greater depth and transparency to the music.  I could not find any fault with the new Preamp.  Everything just sounded better.

I next paired the new DAC and new Preamp with my A21 amp and I was astounded by the sound.  Any hint of digital edginess and fatigue was gone while the music sounded very natural.  The DAC's slight lack of detail was improved.  There was even more musicality.  The attack was fabulous. Cymbal crash was excellent.  If you closed your eyes you would think that the Cymbals were right in front of you.  Bass was even deeper still, and the combination really brought out the best in my Parasound A21.  Truthfully, I did not think that the A21 could sound so good.  The A21 always seemed to have a little graininess but the DAC-Preamp combo removed any grain that I could hear.

Finally I hooked all 3 pieces together and got down to some prolonged critical listening.  The first thing that I noticed was that the music evoked and emotional response.  There was shear joy and pleasure listening to this combination of gear.  The depth of the music increased along with transparency and sound stage which is hard to do in my experience except with very expensive gear. I have found that when you add depth the music becomes less transpent. Not so here.  The combo was extremely musical, fast with clean, non fatiguing, very detailed treble.  Bass was fast, deep, powerful and controlled.  Instruments and vocals had great separation, I was able to pick out each instrument in space.  The sound had a holographic sense to it.  The midrange was to die for and was not too foward or recessed.  It seemed just right.  The overall tone of the combo was neutral to just a hint of warmth.  My son and I can be overly critical about music and we tried to find fault with this combination and we both kept on saying that the music just sounds right and that we would not change a thing about the sound.  Even my wife who has a good earand will sit and listen to music a couple of hours at a time with me, commented on how good the sound was.

Sadly, the time had come for me to return the gear to Mr. Van Alstine, but before I did, I decided to try the 400R amp in combination with my Ultra II preamp and DAC (Previously I had the opportunity to reivew its more powerful brother the 600R).  I was not disappointed.  The amp still maintained its attributes, effortless power, speed and bass.  The sound is very detailed with well rounded from the high to the low frequencies.  The sound stage was huge and very transparent.  I could not detect any difference between the 2 amps.


Music used-

Eva Cassidy
The Best Audiphile Voices XRCD
Patricia Barber
Boxer Rebellion
John Lee Hooker
The Hot Spot Sound Track
The XX
Various Classical CD's
George Winston
Traffic
Fleetwood Mac
Blue Coast Collection-the E.S.E. Sessions 24K Gold Audiphile Reference CD
Tim Gorman-Piano Variations
Garett Brennan
Buddy Guy and Junior Wells
several other CD's and XRCD's.

Other gear that I am familiar with-

Bryston, Plinnius, Mac, Conrad Johnson, Belles, Luxman, Theta, Cambridge Audio, Ayre, Anthem, NAD
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 27 Jan 2012, 04:19 am
Making me anxious to get my hands on my FET Preamp.  Can you elaborate on the preamp's connections and controls, what's the remote like?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 27 Jan 2012, 11:00 pm
Mr. Peabody,  your preamp will be finished and shipped late next week.

Here are the controls and functions it has:

The back panel has six sets of line inputs, plus tape in, tape out, and two sets of audio outputs.  The back panel also has the main system fuse, an IEC power input jack, and a "ground lift" switch to connect or disconnect the third wire AC ground. This is useful to eliminate ground loop hum in some system configurations.  Input 1 jacks are used for the RIAA phono inputs if this option is incuded.

The front panel contains the rotary selector switch, the precision volume and balance controls, the push button  power switch, and the pretty soft blue LED on indicator.  If also has four push button switches; Input/Tape, Stereo/Mono, Low Gain, and Filter functions.  It also has a headphone jack, driven by a unique unity gain high current buffer, complete with its own regulated power supply.

Inside the Fet Valve preamp reside the double sided full ground plane shielded main mother board, the shielded toroid power transformer, and the remote control receiver board (if so optioned).  The remote control option includes a custom made motor driven precision volume control and a small sender.  It provide volume up or down and a mute function. The mother board includes 5 regulated power supplies for the main tube/hybrid audio circuits, the hybrid audio circuits themselves, and provisions for adding three more optional circuit sets; RIAA phono, tape buffers, and inverters, along with their additional regulated power supplies if so optioned.  The preamp uses two 6CG7 dual triode vacuum tubes.  6SN7 tubes can be used with appropriate socket adaptors and with the cover off.  Several other dual triodes with the same pinout as the 6CG7 may be played with.  Some of these will substantially change the gain of the preamp, either up or down.

The preamp also contains time delay turn on and instant turn off circuits to eliminate any possible significant on or off transients, protecting your speakers and amplifier.

The preamp also has the provision for optional balanced line out circuits with XLR fittings.  In addition, one set of balanced line in circuits can optionally be accommodated.  These offer no musical advantage, but will allow interfacing the preamp into a system where balanced line connections are necessary.

The actual hybrid tube audio circuits are a combination of John Broskie's Aikido tube circuits with our own power mos-fet follower design.  There is no global feedback in this design.

We think you will enjoy it

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 28 Jan 2012, 05:41 am
Thanks Frank.  Curious at to what the filter button does.  The headphone stage is a nice touch.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 31 Jan 2012, 04:24 am
Any one use the AVA phono stage?  If so, what do you think?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: festuss on 31 Jan 2012, 10:42 am
Phono stages are terrific, silky smooth. noise free, bargain for the high quality sound it allows.  Like everything AVA.  Super reliable also.  So good I bought 2 in the Ultra Hybrid pre amps. One a bit newer, with a few ckt updates, all good.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 4 Feb 2012, 08:44 pm
Yes, the FET Valve is one musically satisfying amp.  It does seem to do everything right.  One of my friends couldn't believe just swapping out the amp could make such a difference in a system. 

I through on some harder Rock last night and it helped me to realize even more how accurate the amp is, and it doesn't add to the recording, my first impression paying atttention to the double kick bass drum I was a bit disappointed in the impact but as the bass guitar came in playing deep with a nice presence I realized the kick drum is actually pretty high in the frequency and wouldn't have impact like I was expecting.  This would be recording dependent but held true in what I was listening to.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 4 Feb 2012, 09:02 pm
I have the Insight+ phono board in both of my preamps. Very, very good.

Wayner
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 4 Feb 2012, 09:46 pm
Mr. Peabody,  your preamp will be finished and shipped late next week.

Here are the controls and functions it has:

The back panel has six sets of line inputs, plus tape in, tape out, and two sets of audio outputs.  The back panel also has the main system fuse, an IEC power input jack, and a "ground lift" switch to connect or disconnect the third wire AC ground. This is useful to eliminate ground loop hum in some system configurations.  Input 1 jacks are used for the RIAA phono inputs if this option is incuded.

The front panel contains the rotary selector switch, the precision volume and balance controls, the push button  power switch, and the pretty soft blue LED on indicator.  If also has four push button switches; Input/Tape, Stereo/Mono, Low Gain, and Filter functions.  It also has a headphone jack, driven by a unique unity gain high current buffer, complete with its own regulated power supply.

Inside the Fet Valve preamp reside the double sided full ground plane shielded main mother board, the shielded toroid power transformer, and the remote control receiver board (if so optioned).  The remote control option includes a custom made motor driven precision volume control and a small sender.  It provide volume up or down and a mute function. The mother board includes 5 regulated power supplies for the main tube/hybrid audio circuits, the hybrid audio circuits themselves, and provisions for adding three more optional circuit sets; RIAA phono, tape buffers, and inverters, along with their additional regulated power supplies if so optioned.  The preamp uses two 6CG7 dual triode vacuum tubes.  6SN7 tubes can be used with appropriate socket adaptors and with the cover off.  Several other dual triodes with the same pinout as the 6CG7 may be played with.  Some of these will substantially change the gain of the preamp, either up or down.

The preamp also contains time delay turn on and instant turn off circuits to eliminate any possible significant on or off transients, protecting your speakers and amplifier.

The preamp also has the provision for optional balanced line out circuits with XLR fittings.  In addition, one set of balanced line in circuits can optionally be accommodated.  These offer no musical advantage, but will allow interfacing the preamp into a system where balanced line connections are necessary.

The actual hybrid tube audio circuits are a combination of John Broskie's Aikido tube circuits with our own power mos-fet follower design.  There is no global feedback in this design.

We think you will enjoy it

Frank Van Alstine

hi Frank,

two things:
What do you use for this "precission" volume control?
And tell me more about the filtering switch? Is that for high and low and what freqs and slope do you cut off at?

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Tone Depth on 4 Feb 2012, 11:32 pm
Remote control announcement:  http://www.audiocircle.com/index.php?topic=13537.0 (http://www.audiocircle.com/index.php?topic=13537.0)

hi Frank,

two things:
What do you use for this "precission" volume control?
And tell me more about the filtering switch? Is that for high and low and what freqs and slope do you cut off at?

Ray Bronk
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Lefty052347 on 7 Feb 2012, 01:13 am
Ray:

The switch ativates a high and low filter.  The filters are 6db per octave.  They are down 3db at 22khz and 22hz.

Regards,
Dean
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 7 Feb 2012, 04:06 am
The switch ativates a high and low filter.  The filters are 6db per octave.  They are down 3db at 22khz and 22hz.

So the low filter is to cut off turntable rumble, and the high filter is to cut off digital extracurricular data?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Wayner on 7 Feb 2012, 12:55 pm
There is only one switch, so it does both at the same time.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 9 Feb 2012, 08:50 pm
Hello Audio Experts!
  Well, happy days are here again; I got my FetValve 400R upgrade delivered!

  I upgraded from a 350 '+' FV, the best sounding AVA hybrid before the 400R/600R (I didn't have the double die, but that was just more power?) Doing a direct comparison with the 350'+' amp is difficult.  It's been a few weeks since I sent it in, and I had different tubes in the '+' than in the 400R. 
  That said, I think the 400R is such an advance that the improved sonics are obvious, even with the time delay.  When I got the 350+ upgrade, I thought it had tighter control, especially in the bass.  The 400R brings the rest of the frequency spectrum up to this same high standard.  I'm finding the mids & treble to be more open & airy, more 'present' in the room, & more detailed also. 
  But the biggest difference to me is in the grip this amp has on the individual notes.  Going through a few of my favorite disks, I noticed how the notes were shaped & formed.  This amp catches the notes at initiation, holds them tight to the peak, and then keeps the correct form until the notes decay as they should.  The amp is not a slacker: no approximation, no 'area' shots, no 'good enough'.  The amp doesn't let go until the note is done, period.  This 'corralling' of the musical energy gives the notes better impact since there is no leakage to diminish or spread the sound to where it shouldn't be.
  Listening to HOT TUNA's "Hot Tuna", you can hear Jorma & Jack just bending & torturing the strings.  The harmonica of Will Scarlett just floats.  But whether the music is fast or difficult, the amp never gives in, never loses control for a moment.  I then listened to a bunch of string quartets, & the subtle detailing came through fully.  You could almost see how the bow was moving.  Next up was "Time Out", 'nough said.  The clean details, the amazing feel of the instruments, the mastery of the musicians was all there in extra portions. 
 One thing I haven't mastered when listening to music is the 'space' factor.  I know my room & speaker placement aren't ideal, so I can't really hear when the guitarist takes two steps in that direction....  With the 400R the increased detail & realism improves my ability to place the instruments.  I think this is because the music is so well shaped that the sounds seem to only come from the instruments.  With less energy escaping from the notes, more energy seems to originate from the instrument, thus placing it better on the soundstage. 
  Back to the big picture, the resulting music is magnificent.  That's my opinion, and I'm sticking to it.  My wife got home the other night (voice scholarship, still sings semi-pro) & we listened to some music.  I try to keep her in the dark about my audio spending, but she knew I had the amp upgraded because she sent it from her office. So, she said,
"That Van Alstine thing is pretty good, isn't it?"   
"What do you think?"
"I think yes".
"Can you explain how?"
"Go to hell, bud".
Elizabeth doesn't know an amp from a dac, but she has great ears!

Murf   8)  :thumb:

PS: Frank sent me a cool AVA flashlight...made in China!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: trebejo on 12 Feb 2012, 11:52 pm
Nice review Murf! You give a good impression of a pretty ineffable yet thoroughly noticeable musical effect.

It's hard to improve on the "+" amps (I'll never forget the first impression made by the realistic reproduction of an acoustic guitar's overtones with that amp). Nonetheless the "R" amps manage to do so...
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: murf on 16 Feb 2012, 06:10 pm
This is from Frank's intro blurb:

"Presenting the new AVA Fet Valve R series amplifiers...and finally (and an audio engineering first we believe) active analog regulated power supplies for each power mos-fet output circuit, ten high speed analog high current regulated power supplies in all...."

Ten regulated power supplies?  Do others do this?  :scratch:
I think it was an auto industry ad that said, "Power is nothing without control...."  2x for the amplifier industry!

Murf
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 16 Feb 2012, 09:48 pm
Just for you guys who have not noticed this thread so far:

There are sixteen separate new user reviews of our Fet Valve 600R and 400R hybrid power amps reported already in this thread.

There are lots and lots more shorter comments too.

When you have time, ready and enjoy.

Regards,

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mr Peabody on 27 Mar 2012, 03:54 am
Frank, how is the 400r only 30 lbs?  I'm just curious what is in other 200 watt amps that make them so heavy?

Can a 400r be upgraded to a 600r down the road, if so, what cost would it be?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 27 Mar 2012, 01:05 pm
First of all, a 400R can be upgraded to a 600R for the difference in price between the two units.

Weight?  Simply efficient mechanical design, thanks to Wayner.  No waste parts, no effort to make it heavier than needed to impress the real heavy sounds better bunch.  An excellent shielded toroid power transformer design.  Toroids, by the way are about 30 percent lighter than a comparable standard iron core transformer.  The amp is solid, rigid, and mechanically stable.

A better question might be why are so many powerful amplifiers so heavy that you need a fork lift truck to move them?

Regards,

Frank Van Alstine
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 27 Mar 2012, 08:53 pm

A better question might be why are so many powerful amplifiers so heavy that you need a fork lift truck to move them?

Regards,

Frank Van Alstine


Like my 60lb Parasound!  At least it has handles on the back.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Bigload on 31 Mar 2012, 04:32 pm
My new 400R with black faceplate (to match my other AVA gear) showed up yesterday! :D

I have spent most of the morning listening and I could not be more thrilled with what I have here.  I am using it to replace a very capable AVA Double 260 Insight Plus.  The rest of the system is an AVA Star hybrid preamp and Salk HT2TL's. For sources I am using a Wadia 170i iPod dock (Apple Lossless) with the AVA Vision EC DAC, an Oppo BDP95 using its own internal 2 channel DAC and a VPI Classic 1 turntable with a Benz Micro Glider cartridge.  I do not use anything fancy on cables... just Blue Jeans Cable interconnects and speaker cables.     

Regardless of which source I use, the results are the same.  I have swapped the amps around all morning and I cannot find anything to fault the FetValve on.  It simply does the job in a way that far exceeds anything I have certainly ever owned.  Additional detail is revealed to an unbelievable level.  Soundstage has expanded.  Imaging is distinct and repeatable.  The clarity and subsequent decay of piano key strikes, guitar strings and cymbals are just particularly amazing.  The bass now being produced by the Salks is beyond belief.  It comes through as a very high end musical sub being played... but it is just the 400R and the Salks.  I cannot believe stereo speakers are capable of this, but they obviously are. 

I really did not know what to expect here.  I knew my current system was a great performer.  So, my expectations were skeptical.  But I am sold.  The 400R honestly did bring the system to new level and I just cannot believe it could be much better.... at least anywhere near my current investment and maybe I will even be bold enough to say at any level of investment. 

The media I have been listening to this morning included....
CD-  Jennifer Warnes.... The Hunter
CD-  Steely Dan.... Gaucho
LP-   Diana Krall....Love Scenes
LP-   Pat Metheny...What's It All About
LP-   Patricia Barber....Cafe Blue
iPod- Philippe Saisse...Next Voyage
iPod- Pat Metheny....Life Talking

Thanks again Frank.  Very, very nice job!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: guest1632 on 1 Jun 2012, 06:40 am
Just for you guys who have not noticed this thread so far:

There are sixteen separate new user reviews of our Fet Valve 600R and 400R hybrid power amps reported already in this thread.

There are lots and lots more shorter comments too.

When you have time, ready and enjoy.

Regards,

Frank Van Alstine

Hi Frank,

on your FET Valve preamp, what is served by having a high/low gain switch? Is that just a matter of switching out a gain stage?

Since I understand you have the filter switch as both high and low together, could the high/low gain switch be subed out for one of the filters, thus separating both filter switches?

Ray
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 1 Jun 2012, 01:47 pm
The low gain switch is to make the volume control rotation more useful in systems with very efficient speakers or high gain amplifiers.  It simply attenuates the input signal to about one third of normal.

To separate the high and low filters it would be necessary to design a different switch board and faceplate just for that option - - - way too expensive to offer as an option.

However, we certainly can tailor the the filter frequencies within reason.  Or we could make it a low only or high only filter as desired.  However, this would take the unit to a "special order" status and would not carry our 30 day satisfaction guarantee.

Regards,

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 1 Jun 2012, 11:06 pm
Frank, any hint as to when we might see the upcoming review?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Tone Depth on 9 Dec 2016, 10:29 pm
Bringing this thread back to the amplifier topic:

I purchased a FET Valve 600R during the 2016 Fall Sale, and have been listening to it off and on for the past two weeks. It replaced an Insight+ Double 440H. I immediately noticed a much clearer sound, through my somewhat modest vintage speakers. Next step will be to update my speakers.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: WGH on 26 Feb 2017, 09:31 pm
The Tucson Audiophile Group had a gathering yesterday and Tone Depth brought over his FET Valve 600R to compare to my Synergy 450. The electronics were all AVA, the front end includes a FET Valve DAC and the FET Valve Preamp (previous model, not the CF) with new tubes. Note: if you haven't replaced your tubes in 2 or 3 years - do it! The lower noise floor and restored clarity is worth the $35, just call Frank. Digital was via my home made CAPS server that includes a Paul Pang USB card, three linear power supplies and a data only JMaxwell USB cable (http://www.jmaxwellusb.com/).

Speakers used are my custom mesquite veneered Salk HT2-TL's (http://www.audiocircle.com/index.php?topic=100672.0).

Comparing the two amps was hard, all AVA amps sound very similar. A year ago we compared the Synergy 450 to the AVA Ultravalve Vacuum Tube Amp (35 watts per channel) on a pair of Nola KO speakers and at low volumes there was no appreciable difference. Of course, when bumping up the volume just a little, the tighter, deeper bass and unlimited headroom became obvious.

Once again the sound of the two AVA amps was very, very close. The Synergy 450 was more tube like with a tiny lower midrange bump which made it sound warmer while the 600R was more balanced with a greater clarity in the upper midrange and treble. Overall the 600R was a hair clearer and smoother in it's presentation. Bass is the same and the both amps have excellent center image density with depth, almost everyone asks if my center channel speaker is on (it's not) because the center image is so solid. 

Musically we went through everything from Bach: Goldberg Variations by Glenn Gould (https://www.amazon.com/Bach-Goldberg-Variations-Johann-Sebastian/dp/B0000025PM) to Yello's excellent new album Toy (https://www.amazon.com/Toy-YELLO/dp/B01HFRBHNE).

Here is an accurate representation of what the room looked like when I turned up the volume on a Toy cut to see what 600 watts sounded like:

(http://www.audiocircle.com/image.php?id=158385)

Those HT2-TL's can really rock!

Wayne
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 26 Feb 2017, 10:42 pm
I am shocked that you find both the Synergy and 600R amps to sound similar.  I have heard them side by side at Franks and they sound completely different.  The Synergy being darker and warmer while the 600R was much more transparent, detailed, resolute, with a wider sound stage and punchier bass.  Both excellent amps but definitely different flavors with the R series competing way above its price point.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: WGH on 26 Feb 2017, 11:04 pm
Perhaps my buddies will chime in. Did Frank use his ABX Comparator Switchbox?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 27 Feb 2017, 12:13 am
Perhaps my buddies will chime in. Did Frank use his ABX Comparator Switchbox?

I can't remember.  But I also got to take them home for a review and heard them in my system.  I don't doubt what you heard but what I heard was 2 completely different sounds.  I heard them both with his latest FET Valve preamp and Salk HTR3 speakers at Franks and with my Magnepan 1.6's at my place.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: mresseguie on 27 Feb 2017, 12:43 am
I'd like to chime in for a moment. Last year adcoll and I drove to the Kirkland, WA area to attend Gregfisk's G2G. We brought my Gustard X20u Gustard and my Synergy 400R. One of the participants brought his Synergy 450. We spent a good 45 minutes going back and forth comparing the two amps, but we had a difficult time declaring any appreciable difference in their sounds. It is important to point out the Greg's system has GR Research OB subs that play in the <80Hz range, so his speakers were only reproducing music above that level.

This isn't quite the same situation that WGH and I.Greyhound Fan describe, but it was interesting nonetheless.

Michael
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: alexscotti on 27 Feb 2017, 01:02 am
That was my Synergy 450.  The amps sounded way more alike than different to me, at least in that setup.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: WGH on 27 Feb 2017, 01:24 am
I have heard them side by side at Franks and they sound completely different.  The Synergy being darker and warmer while the 600R was much more transparent, detailed, resolute, with a wider sound stage and punchier bass.

I'm not surprised. The Salk HT3's with a 84 dB sensitivity and the B&W 801 at 87dB/W/m are probably a better match with the 600R.    
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Tone Depth on 1 Mar 2017, 12:01 am
We started out this comparison by briefly listening with the solid state Synergy 450, which served to reset my ears to Wayne’s system. Then we switched amplifiers to listen with the hybrid FET Valve 600R, and I immediately noticed an increased clarity to the music, similar to how the music sounds with the amplifier placed in my system. It was also easier to understand the lyrics being sung, and to hear each note produced by each instrument. The clarity was most evident in the upper registers, and somewhat less apparent in the bass. I agree that the 600R has unique audible characteristics throughout the range of audible frequencies reproduced by the speakers, as compared with the 450. Near the end of the playlist comprising this demo, Wayne turned up the volume to an average sound level indicated to be about 85 dB, per my Smartphone app, and I heard what seemed to be more distortion in the music. I’m guessing that I might have been hearing speaker distortion, rather than amplifier distortion at the higher sound levels. Then we replaced the Synergy 450 in the system, repeated the playlist, and I heard the slight higher frequency distortion I had initially heard. I remarked that it would have been interesting having an ABX Comparator available to be able to easily switch between amplifiers at possibly matched sound levels to compare the sound quality in that manner. I didn’t immediately notice differences in the mid-range between the two amplifiers. I was most impressed by how the solid state and the hybrid technologies both produce great sounding music, and consider both amplifiers to be excellent.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Mike-48 on 19 Jul 2017, 07:45 pm
Yesterday, a friend came to listen who's a professional mastering engineer. His unforced comment about the sound: "I'm jealous."

Photo of the system with AVA Fet Valve 400R and Janszen Valentinas:

(http://www.audiocircle.com/image.php?id=151218)


 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 19 Nov 2019, 07:43 pm
Hi all,

After reading through this entire thread and all of the reviews I could find, yesterday I ordered a new Fet Valve 600R.  It will be used in a system where the primary source is a VPI Prime with a Hana ML cartridge feeding a Bob's Devices Sky 20 transformer to a Vision Q phono preamp.  The Vision Q connects to a Rogue Audio RP-5 preamp.  The speakers are Magneplanar 3.7i's that are crossed over at 35Hz to a pair of MartinLogan 1100X subwoofers.  The 600R has some big shoes to fill - it will be replacing a Bryston 4B SST2 amp which I consider a fine amp, especially for Maggies.  All of the information I could find about the Fet Valve 600R made it a pretty easy choice for me but, in truth, it is the reputation of AVA, and my direct dealings with Frank and others, that sealed the deal.  There are few audio companies out there that offer the value that AVA does, and I can think of very, very few that have maintained a standard of excellence in the same league for such an extended period of time.  I'm greatly looking forward to getting my 600R and will certainly report my impressions to this thread once I've had the opportunity to form them.

LarryRS
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Brad on 19 Nov 2019, 09:21 pm
Yesterday, a friend came to listen who's a professional mastering engineer. His unforced comment about the sound: "I'm jealous."


Nicely treated dedicated room!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: gryphongryph on 2 Feb 2020, 06:34 pm
Larry, how do you like the amp ?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 2 Feb 2020, 07:09 pm
Larry, how do you like the amp ?

Haven't really finished evaluating yet but I do have a couple of comments I can share.  Right now, based on initial listening tests, the Fet Valve has supplanted the Bryston 4B SST2 in a system with Magneplanar 3.7i speakers. The Bryston then was compared in a Magneplanar 1.7i system to a Parasound A21.  The result was that the Bryston replaced the Parasound.  I still have much more listening to do before impressions are finalized.  I heard Sheku Kanneh-Mason in concert the other night and was planning on listening to his "Inspirations" this afternoon to get a better handle on the sound.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 12 May 2020, 09:44 pm
Below are some updated impressions on the sound of the FET Valve 600R in my system.  It is currently in a system with Magneplanar 3.7i's where, as I mentioned previously, it replaced a Bryston 4B SST2. My first impression when I substituted the AVA for the Bryston was that I had lost some high frequency detail. But as I kept listening, it seemed that what I was hearing sounded more natural than it had. I was fortunate enough to attend a live Sheku Kanneh-Mason concert right around the time that I was comparing the amps. The sense of more life-like sound (for lack of a better term) was very evident on recordings of his cello (I had bought some of his recordings at the concert). A fellow concert-goer, who also happens to play cello, agreed - pointing out to me that the 600R sounded more natural than the 4B SST2 before I made any comment about my impressions.

In a lesson in system synergy, maybe, another comparison was made by swapping between the Bryston and a Parasound A21 in a system with Magneplanar 1.7i's. Here the Bryston's high frequency balance, which had seemed a bit too much with the ribbon tweeter 3.7i's, meshed very well with the quasi-ribbon drivers of the 1.7i's.

LarryRS
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 19 Jun 2020, 11:00 pm
A question about the 600R.  I've now been listening for a few months to the 600R and my overall impressions of the sound quality have not changed - the natural tone of the amp is really very enjoyable in my system (some details of the system below).  I do have a question though concerning the imaging/soundstage.  A consistent difference in the presentation of the 600R vs. other amplifiers I have had in that system is the size of the image.  The height of the image produced with the 600R is less than that of the Bryston 4B SST2 that it replaced or a Parasound A21 that I had in that system.  This is apparent on many recordings but is striking on some.  A good example is the cut "Chameleon" on the MoFi LP version of Herbie Hancock's Headhunter.  On that cut the image with either the Bryston or the Parasound extends from wall-to-wall but also from floor-to-ceiling - some sounds seem to come from the upper corners of the room behind the speakers on both the left and the right.  With the 600R, the sounds seem to pretty much come from wall-to-wall but they definitely do not extend as high (e.g., the sounds extend maybe 2/3's of the way up).  Is the image height and width something that is likely to be affected by the tubes in the 600R?  Has anyone replaced the JJ tubes that it comes with it and noticed a difference in the image?  I should also mention that the image also shifted just a little bit to the right with 600R and that the image changes are apparent independent of the source.  Thanks in advance for any information/opinions.

LarryRS

Preamp - Rogue Audio RP-5
Speakers - Magneplanar 3.7i/Martin-Logan 1000X subwoofers
Sources - Oppo BDP 103 disc player/Bluesound Node 2/ turntables: VPI Prime (Soundsmith Zephyr MIMC ☆); Dual 1219 (Shure V15 Type III w/JICO SAS); Technics SL1200 MkII (Grace F9 w/Soundsmith Ruby OCL)
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 19 Jun 2020, 11:50 pm
I reviewed the 600R for Frank.  I did not notice a drop in sound stage compared to my Pass amp.  Tube rolling does make a difference.  I have a friend that has a 400R with Magnepan 1.7's and he rolled tubes and the sound was much better.  I also have a friend that has the 3.7's with 2 600R's and they sound great with a huge soundstage.  The preamps used are the AVA FET Valve in both systems.

No surprize that the Bryston sounds better than the A21.  I gave my A21 to my son.  It is a nice amp that was a bargain for a while.  The new A21+ is much better.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 19 Jun 2020, 11:55 pm
I've got some vintage Tung-Sols on the way for the RP-5.  We'll see what effect they have.  Any idea what tubes your friend settled on?
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 20 Jun 2020, 12:23 am
You can PM him.  Tell him Larry in Woodbury referred you.  PM him at edn4x4 

If he does not get back to you, I will email him.

Regards,

Larry
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: aln on 20 Jun 2020, 12:38 am
Be sure to share the 12at7’s used with the rest of us.  Inquiring minds want to know.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 20 Jun 2020, 10:28 am
You can PM him.  Tell him Larry in Woodbury referred you.  PM him at edn4x4 

If he does not get back to you, I will email him.

Regards,

Larry

Maybe I'm not doing something correctly but, for some reason, I can't message him at that address.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 20 Jun 2020, 11:49 am
Maybe I'm not doing something incorrectly but, for some reason, I can't message him at that address.

I will send him an email.  It may be a few days before he answers.

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 20 Jun 2020, 12:33 pm
Thanks.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 20 Jun 2020, 12:57 pm
My email is frank@avahifi.com. You may be sending to an obsolete address.

I try to answer all within 24 hours, but a few may wait longer on weekends when I am not at the business computer.

For a quicker response just call me at 651-330-9871.  I answer the phone 7 days a week as long as I am home.

It is a land line so not answered when I am not here.  In that case leave a message.

Regarding the 600R, any good quality 12AT7/ECC81 tube will work. We have e excellent results with the JJ brand we supply in new units. 

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: avahifi on 20 Jun 2020, 02:43 pm
If you have a channel balance issue, the first step is to swap the two tubes from channel to channel and determine if the issue follows a tube.

Frank
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 20 Jun 2020, 05:34 pm
I planned to do that - although I'm not so sure it is an imbalance as much as a difference from my other amps.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: brusson on 20 Jun 2020, 07:36 pm
I was curious about the possibilities of tube rolling my 600R and found this thread after a Google search: https://www.audiocircle.com/index.php?topic=104025.60.
After reading, I decided to try a pair of the 6201/12AT7 Sylvania GOLD BRAND. I heard a difference right away, although Brent Jessee said they'd take about 40 hours to break in. They have gotten better over time.
I like a big sound stage and have set up my room and speakers (Salk 9.5) accordingly. Although the results vary with the recording, especially with the best ones, the sound stage is wider and deeper, and individual instruments are localized within.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: LarryRS on 20 Jun 2020, 10:06 pm
brusson,

Thanks very much for the information.  I will take a look on the Brent Jesse site right away.  Thanks again.

Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: I.Greyhound Fan on 21 Jun 2020, 01:57 am
LarryRS, Here is the link to the tubes that my friend bought and loves-

https://www.tubemuseum.org/ProductDetails.asp?ProductCode=SH%5FECC801S+BWB

Siemens NOS ECC801S, they are pricey.

Cheers,

Larry
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Hydro on 21 Jun 2020, 05:20 pm
I have rolled a lot of tubes in my 400 and 600R amps. NOS Mullard tubes have a great soundstage with more depth than any other tube, they also have a more "tube" sound as in lush. Gold Lion cryo tubes are more neutral but still have the huge soundstage. Sylvania are the brightest tubes that still have good bass, excellent imaging, about half of the Sylvania tubes I have tried are at least a little microphonic. Tung Sol are bright but thin on the bottom end. RCA are very neutral but don't open up like the Mullards and Gold Lions. GE JANS are really good tubes in all respects and could be a great choice in some systems, but I like the Mullards the best
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 22 Jun 2020, 11:44 pm
I like the Valvo 6201 Blues the best.
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: Hydro on 23 Jun 2020, 04:13 pm
Valvo didn't  make their tubes, just sold others under the Valvo name. Where were the 6201's you have made, tonyptony? If in West Germany they are probably Siemens, Holland would be Amperex or Great Brittan would be Mullard. Valvo tended to sell premium tubes from whatever manufacturer they bought from. 
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: aln on 24 Jun 2020, 09:10 pm
Great stuff here-I am using the Sylvania 6201 gold pin in my 600R but want to try something different in the near future.  Thanks for the great ideas!
Title: Re: User reviews of our new Fet Valve 600R & 400R amplifiers
Post by: tonyptony on 3 Dec 2020, 12:09 am
Valvo didn't  make their tubes, just sold others under the Valvo name. Where were the 6201's you have made, tonyptony? If in West Germany they are probably Siemens, Holland would be Amperex or Great Brittan would be Mullard. Valvo tended to sell premium tubes from whatever manufacturer they bought from.

Hydro, better late than never I guess! :D I’ve been putting a new house together so I’ve been away from the sites. I’m pretty sure my Blue labels were made in Germany. They are pinched waist varieties, although I know there were a number of variations in these. Most of what I have are df1 variants. A few of other dc variants.