I've made up my mind

Devil Doc · « **on:** 19 May 2011, 07:17 pm »

My next amp and pre-amp will be AVA products, which ones the fella that answer the phone will help me decide, but I can use a little help. I can't afford to upgrade both at the same time. I'll do one shortly and then one a little bit down the road. I'm presently running a PS Audio 6.0 pre and a B&K ST-140 power amp to drive my Vandy 2Ci's. They've served me well for 20yrs. In all that time I've blown a single fuse in the pre and never had a single issue with the amp. So the question is for you kind gentlemen, which would you upgrade first and why? Thanks in advance for your suggestions.

Doc

AVnerdguy · « **Reply #1 on:** 19 May 2011, 07:27 pm »

I don't know much about the pre but I do know the ST-140 very well (I fix a lot of those). I'd get the amp 1st. The ST-140 is kind of lacking on both the highs and the lows compared to what you would get with a current amplifier. Good in it's day but the change will be amazing. I think the sound stage, detail and extended low end of the new AVA amps is excellent. Also, if your source has a variable output you could go straight to the amp.

pardales · « **Reply #2 on:** 19 May 2011, 07:38 pm »

You could upgrade both with the AVA control amp (integrated).

Opus Flatus · « **Reply #3 on:** 19 May 2011, 08:00 pm »

DOC, I'd go with the AMP upgrade first. I have the Insight 240 and it's alot more open than the ST-140. By the way, the ST-140 is Frank Van Alstine's design stolen by B&K. His preamps are also very nice - I have three. I bought them used and had two upgraded by AVA, to ULTRA+ and Insight in Dynaco PAT4 chassis. The last, a SUPERPAS3, I used the AVA rebuild kit. The ULTRA+ is my favorite; really outstanding with my U70. I used my tax free money earned in the CENTCOM AOR for my upgrades

Devil Doc · « **Reply #4 on:** 19 May 2011, 09:20 pm »

Must be a Jarhead. Who else would capatilize all three letters in Doc?

Doc

trebejo · « **Reply #5 on:** 19 May 2011, 11:17 pm »

A consensus seems to be building towards getting the amp first.

That's how I did it too, amp, then dac, then preamp. The biggest difference came with the... dac. The emphasis is on the word "difference". It depends on what is being replaced.

I would suggest that you get whichever piece you are most certain of. Amps have to be paired up with speakers and thereby wait a few branch points in your decision tree (e.g. wattage). Preamps have to be matched up with entire systems and they tend to come with quite a few options already, but let me specifically mention the phase inverter, which is not only very nice but fun too.

Oh yeah, and you'll have to decide how many tubes you want--none, full tube, or just the input stage.

In your position, I would choose the amp first, but having gone through the cycle now, I'd take a good long look at getting the preamp first.

Or you can let the market decide, put them both up for sale and see which one leaves first. Nice problem.

simon wagstaff · « **Reply #6 on:** 20 May 2011, 12:51 pm »

How much volume do you wish for? I am going to put in a big plug for the U70 but am not sure if there will be enough bass grunt for the Vandys but I would bet they would sound very sweet with a U70. I am not sure if your budget would allow for a pair of them in bridged mode with the AVA pre-amp.

I am sure there will be a lot of folks who like the AVA more powerful solid state stuff but I really love my U70 (now ultravalve)

murf · « **Reply #7 on:** 20 May 2011, 03:06 pm »

I never would have guessed that so many AVA owners also had st-140s! I put mine in the main system when I recently sent my fet-valve ultra 350 amp (?) in for the "+" upgrade. The st-140 is still a very enjoyable amp, but no comparison with the Fet-valve ultra +. In fact, I couldn't wait to get my AVA amp back. I would say the same about the HK Signature amp which I also have: v. nice, but the AVA is soo much better, it's crazy.

Murf

avahifi · « **Reply #8 on:** 20 May 2011, 03:29 pm »

What is the impedance and sensitivity of your Vandi 2Ci speakers?

Inasmuch as your B&K 140 only puts out 60 watts per channel (they never did make their advertised power rating, simply measure the power supply rails) you might very well find that our Ultravalve vacuum tube amplifier will be a great match.

If your speakers are 87 dB efficient or better, that would be my first recommendation for you.

Best regards,

Frank Van Alstine

Devil Doc · « **Reply #9 on:** 20 May 2011, 04:27 pm »

Impedance: 7 ohms nominal. 4 ohms minimum
Efficiency: 88dB, 1watt - 1 meter
The thing is I'm not sure I want to get involved with tubes, and I would like some flexibility. You never now when I might get the itch for new speakers and I wouldn't want an amp that could limit my choices too much.
Thanks for all the responses so far. I really appreciate it. I would have changed the Pre first. Obviously, not the way to go.

Doc.

martyo · « **Reply #10 on:** 20 May 2011, 04:58 pm »

Quote

Thanks for all the responses so far. I really appreciate it. I would have changed the Pre first. Obviously, not the way to go.

I think you will find just as many folks recommending changing the pre first. That is how I did it.

Quote

The thing is I'm not sure I want to get involved with tubes, and I would like some flexibility. You never now when I might get the itch for new speakers and I wouldn't want an amp that could limit my choices too much.

If that flexibility is what you want, then the Ultra Double 550+ offers the most of Franks currnet production amps. 300 a side into 8 ohms. There is one small signal tube but it is a hybrid amp so the outputs are SS. The tube is inexpensive and standard ones will last for 5K hours, most likely more. You will be rewarded with that richness of sound that is a key element of why many want some glowing glass in the signal path. 300 watts might be considered overkill, but it will give you the flexibility you want and headroom in an amp is always good.

murf · « **Reply #11 on:** 20 May 2011, 06:41 pm »

"Inasmuch as your B&K 140 only puts out 60 watts per channel...."

Frank,
Didn't the later st-140 amps put out more power (the amps with the blue & red faceplate writing) than the early ones?

Murf

Devil Doc · « **Reply #12 on:** 20 May 2011, 06:55 pm »

Quote from: murf on 20 May 2011, 06:41 pm

"Inasmuch as your B&K 140 only puts out 60 watts per channel...."

Frank,
Didn't the later st-140 amps put out more power (the amps with the blue & red faceplate writing) than the early ones?

Murf

My 140 is advertised as being 105W per channel. The older version 70W. I'm sure it's more than 60W. I play it loud and it's never clipped. I'm sure I would have destroyed my speakers by now. they have a rep for not talking a lot of abuse.

Doc.

smwick · « **Reply #13 on:** 20 May 2011, 09:27 pm »

I recently purchased, but have not yet received, an AVA amp and the dac/pre combo. After speaking with Frank I decided on the Fet Valve Ultra + 350 double. Being a tube and SS hybrid should prove to be a very rewarding experience. If you can swing a Fet vale, that would be my recommendation. Also the Dac/Pre would be a nice addition later on as well.

Lefty052347 · « **Reply #14 on:** 20 May 2011, 10:04 pm »

My argument for changing the pre-amp first:
Our experience with 80's vintage AVA designs is that our older amp designs show more improvement with our current pre-amps than the other way around. Op-amps from the 80's don't come close to those produced today. The T-2 pre-amp was a totally discrete design and does a lot better. So, if your PS Audio 6.0 pre-amp is a discrete design (no op-amps) it would be a closer call.

Also, If your budget allows, I would have have a tube in either the pre-amp or the amplifier.

Regards,
Dean

Devil Doc · « **Reply #15 on:** 21 May 2011, 12:05 am »

Thank you Dean. I actually still have my pre-amps manual and it states I have a current sourced Bi-discreet class A FET output stage. I have no idea what that means, but I'm assuming no op-amps and a more difficult choice.

Doc.

JerryM · « **Reply #16 on:** 21 May 2011, 01:28 am »

Myriad upgrade options.

This matters: What is your budget, both for the better immediate upgrade, and then the next? (Regardless of your first choice, amp, pre or DAC)

Have fun with this part,

Jerry

simon wagstaff · « **Reply #17 on:** 21 May 2011, 03:00 pm »

posting only because Frank agreed with me....

I have not found a tube amp to be a hassle to deal with. check the bias every few months just for the heck of it, more often if I feel like it. i did have a rectifier tube go up in a somewhat entertaining fashion but I expect this to be a thing of the past with the diodes I installed. I have the U70, not the Ultravalve.

with EL 34 tubes the amp projects a bubble of sound into the room like nothing I have ever heard. It is almost palpable. When I switch to the KT77 output tubes the bubble is now inverted and I can almost look into it.

The microdynamics and percussion and cymbal splashes on something like the SACD of Caravanserai can be almost startling.

if I were looking for other speakers I would want them to match the capabilities of the amp and not think about changing the amp. I have mine matched up with a pair of Infinity IM 4.1. They have an 850 watt sub amp built into each speaker so the amp only sees a full load above 80 hz.

The vandy's are nice speakers as well and I am sure whatever you do it will sound nice.

Carl V · « **Reply #18 on:** 21 May 2011, 03:37 pm »

Many Moons ago my first serious Hi-Fi was the popular Vandi 2Ce
driven by cj PV5 & cj MV-50. I next went to 2 MV50's, added a 2W
sub (s). Upgraded the MV50 to MV52. Went to 2Ci & Signature then 3s signatures.
Along the way was a a few SS amps & Pres Krell & Jeff Rowland or Tubes ARC.
The systems is still in operation & sounds good.

Tubes were never that much of an issue. They are great tone amps. Pick your flavor.
And AVA has some great choices.
SS amps have some coloration & Pre amps start the whole color ball rolling.

Dean's advice & opinion is pretty solid.

In your case try to audition some of your choices. Used market may help to
extend your budget.

trebejo · « **Reply #19 on:** 21 May 2011, 06:45 pm »

Quote from: simon wagstaff on 21 May 2011, 03:00 pm

The microdynamics and percussion and cymbal splashes on something like the SACD of Caravanserai can be almost startling.

Ah yes... I have been using Moonflower as a reference for the same reason! The more you concentrate, the more you can pick out the different percussive parts, which sound less and less "musically chaotic" and more and more organized as your stereo gets better. Whether it's the U70 or the 550, you get this either way--the amps are different, but not when it comes to this ability.

The AVA components are so good that Mozart could have probably written down the score to this music after a couple of listens. With a lesser stereo, one still very much gets the sense of the musicality of these songs, but with greater clarity we can perceive a far greater sense of organization in the performance. They're no longer just a bunch of guys jamming fantastically, they actually seem to have practiced the tunes before.

Frank makes a little speech about how you need to listen to your records all over again after you get one of his pieces, and I would say that Santana's music from that time period is excellent material for confirming that advice.