[sabes]

I'm using the sig 70's in a smallish (11x15x8) room with vinyl and squeezebox sources, through tyler acoustics linbrook signature monitors, and have been thrilled with them since the day Vinnie first let me audition them. I just spent a great weekend with my college roommate, best friend and fellow ac member, robert57, doing little else but doing system comparisons (ok, we did manage to squeeze in a frank kimbrough trio show (with John Hebert and Matt Wilson) at firehouse12 in new haven (75 seats in an active recording studio - wonderful), followed by a fantastic malaysian meal (ya with me, Vinnie?!)), and I needed to report back in.

One of the things that I've been wanting to figure out is whether or not to use a preamp with the 70's. Now, Vinnie has very definite ideas about this, and while I have a phenomenal amount of trust in his judgment, I'm also a stubborn guido who has to check things out for himself. Except that the 70's replaced an integrated amp setup, so I didn't have a pre.  But I did have a singlepower mpx3 headamp. So I called Mikhail at Singlepower and he retrofitted my mpx3, making it a full-function preamp as well.  That took a bit of time (from November to mid-January.  But, as soon as the mpx3 arrived,my music server coughed up another hard drive (3rd one!).  So I've been listening to lots of vinyl over the last couple of months while fighting with seagate, etc, etc, and have established that I really like the sound of vinyl with the pre, but like it just as well direct to the sig's (yes, rob, i did some more testing after you left!).  But until this weekend, I hadn't A-B'd the squeezebox with and without the pre.

Well, the results are in. Vinnie's right (isn't he always?) - MUCH prefer the sb2 direct to the sig's - cleaner, more detail without losing any richness, better bass - really, in every way a sizeable improvement. Now I made some additional tweaks (upgrade to black sands silver mkV pc on the power supply for my modded sb2, port plugs for the linbrooks, new jumpers for speaker cables, etc.) to the system, and it absolutely glows. My experience is much more limited than many of the contributors to ac, but I have listened to a great many systems over the past few years, and this setup is not embarassed by any I've heard.  In fact, we had made an expedition to listen to an extremely highly regarded amp (by folks here as well as in the audio press) which is double the sig's price, through a pair of top notch electrostatic speakers, and we both felt very comfortably that the sig 70 setup equaled or bested anything we had heard on our road trip.

In sum, I could not be happier with my purchase, and my co-conspirator this weekend was in full agreement.  We had any number of "oooh-aahhh" moments listening to things like Nils Lofgren's "Keith Don't Go", Edward Rosser's lovely rendering of Debussy's "Clair de Lune", and heard the bass solo from The Bad Plus' "Keep the Bugs Off Your Glass..." like I've never heard it before - it was live, right in front of me. Thank you again, still, Vinnie - these amps are a gift every time I sit down to listen (and I'm listening more as a result!).

[topround]

Late.. very late, last nite we hooked up my Mapletree Ultra 4 se tubed pre(12sx7 tubes) with a sig 30.
Speakers were heavily modded Klipsch CornScala speakers, big and efficient.
I had always wanted to hear that sig 30 in a system with my pre. What I heard was delicious. The transparency, speed and Prat, coupled with great tone was amazing!!
I can see why people flip out over this thing.

Now I am no big fan of passive preamps, they do bring you a step closer to the music I believe but at a cost of musicality(for me that is) I am not here to start a war, I prefer an active tubed pre. My ears are wired that way. And I am no expert at this stuff.
I believe the Mapletree added a touch of warmth that just added to the greatness of this amp, it made something so musical even more so. There are no absolutes in this crazy hobby and it is all subjective to a degree. My experience last nite was wonderful.

[sabes]

There are no absolutes in this crazy hobby and it is all subjective to a degree.

agree with you wholeheartedly. 

[Vinnie R.]

Thank you again, still, Vinnie - these amps are a gift every time I sit down to listen (and I'm listening more as a result!).

Hi Sabes,

Thanks for the follow-up!  Sorry I couldn't join you guys... sounds like you had a good time. 

Between your post and Toprounds post, you can see why I believe that it is important that people try it both ways if they can to see what works better for them and in their system.   

Larry Borden of StereoTimes.com is next in line for reviewing the Sig 70s (with a few different speakers, including DeVores) and I asked him to try them with and without a tubed preamp and to comment on that. 

BTW, will you or Robert57 be attending the Montreal Show next month, or the Stereophile show in NYC in May?  Hope to see you guys there!  We also need to get together again at my place... these Omega Super 3 Hemp XRS Dipole prototypes that I'm testing are amazing!    You got to hear them with the Sig 70s!

Thanks again,

Vinnie

[jrebman]

Sabes, first I want to thank you for starting this discussion.  At just about the time you posted this I was seriously considering selling my Signature 70s (and Vinnie was aware of this).  Why, you ask? As I try to answer, keep in mind that I don't exactly know -- these amps are damned near perfect in that they are flawlessly quiet, incredibly dynamic, very smoothe from top to bottom and have plenty of extension at both ends of the spectrum.  So why is it that when I sat and listened to all this incredible sound something just felt like it was missing?  I don't exactly know -- perhaps it had to do with imaging and soundstaging (which aren't my highest priority anyway), warmth which the 70s have in very nice proportion), or whatever.  Vinnie, myself, and others suggested that I try a tube preamp in the system to see if that would give me what I wanted.  Consider also that the system I am speaking of was simply a stock Denon 2910 player, a pair of Anti-ICs directly to the signature 70s, and speaker wires to my Adagios.  I suspected the source had something to do with it, but this same feeling of "something missing" was even present with my Audio Aero Capitole, which had an incredibly smoothe tube output section.  This is probably why I took so long to come around to the idea that tube preamp in the system was going to make any kind of significant difference.  Also there was the issue of money for a decent preamp, and beyond that very little room to put one even if I found one that I could afford.

I considered many, and almost pulled the trigger on a couple before finding the one I settled on.

I won't go into the whole story (that's for a longer review of the preamp itself, which will come in good time as I really give it thorough consideration, roll some tubes, and get enough different kinds of music through it), but one thing lead to another and I eventually hooked up with Bill O'Connell of Morning Star Audio -- importers of the Eastern Minimax line of tube gear.  Bill, like Vinnie, Louis, and so many other AC manufacturers) is one of the real good guys in this business and truly wants his customers to love their music and the gear they buy from him.  So, back to the story... I came around to thinking that the Minimax preamp may be what I wanted and Bill offered to put me in touch with another guy who had one of his modded preamps in front of his Sig 30s but was also looking for that special something from his system.  I had some correspondence with this person and he had had every iteration of the Minimax preamp, including a couple flavors of modded ones -- the latest generation of which he said was the best bang-for-the-buck preamp he had ever heard, and also bested his significantly more expensive Levinson when combined with the RWA Signature amp.

I gave it a shot.  Bill sent the preamp directly to the engineer for modification, and then it eventually arrived here and I put it into the system.  Ok, so now the system has the multiplayer connected directly to  the preamp with a pair of Anti-ICs, and the output of the preamp is connected to the Signature 70s with another pair of Anti-ICs.  I put the stock tubes in the preamp, plugged it in to an elcheapo power strip alongside the plug for the denon (using the included power cable) and flipped it on and went away for 30 minutes for it to warm up.  BTW, I may be insane but I also feel the Signature amps sound slightly better after about 20 minutes of being turned on.

I'll pause here and save this and then continue in the next post...

[ebag4]

well come on Jim, don't keep us in suspense!!

[jrebman]

The story continues...

I was now ready for my first listening session, and more than a bit nervous to hear the result.  Here I was, with a new preamp that has already been modded, new tubes (which always sound veiled to me) and recollections of other tube gear, most of which added significant warmth, rounded off the edges, damped the dynamics, and always, always (with the exception of the Capitole) added significant noise.  I hate tube rush and hum -- maybe because I don't have my sense of sight I am more sensitive to it than most (which is in no way meant to imply that I hear any better -- my brain just pays more attention to auditory information than the average person), and of course there is the problem of tube "bloat" in the midrange.  I love the dimensionality of good tube gear and the harmonic body and textures that a good SET can reveal and present in a very palpable way -- the wood of a guitar or cello, the head of a drum and it's trailing resonances, and so on.

Ok, everything is warmed up, a small stack of CDs from several genres and that I'm intimately familiar with sitting next to the Denon, and I'm ready to begin...

Hmmm, no sound -- Ah, you have to select the correct input, idiot!

Ok, now over to the listening position and start the first CD.  It took an eternity for it to start and then... all I can say is WOW!

So, what was there?  Well, let's see, there was the full force of the music, all the extension and dynamics intact, more of that "harmonic body" across the spectrum, and a soundstage that was at least 30% larger with great imaging.  The presentation was a bit forward compared to the original passive setup, but I figured that to be the stock tubes, or at least something some tube rolling could take care of.  I'm not worried.  There was one more thing that was there which I was not expecting at all -- more, yes, more, detail -- something which I was thinking was going to be lost to some degree with the tube pre.  When I can hear background singers taking breaths between phrases, I know it's good.

So, what wasn't there?  Noise.  Noise wasn't there and that stunned me.  I had become very accustomed to the black background of battery powered tripath amps having used them for the last year or so.  I like the spaces between notes to be silent now (when they're supposed to be), I like hearing reverberations decay to nothingness naturally, and so on.  This was one of my top priorities for a tube preamp and this certainly didn't disappoint.  Ok, that out of the way, it was on to the next thing -- detail, and as I have said, there appears to be evenn more detail with the preamp in the system  I'm guessing that this has to do with impedance matching in an all-passive system versus the system with an active drive stage -- in fact, I attribute much of what I'm now hearing to that phenomenon.  Dynamics?  There is spades -- no worries here, and again, leading edges seemed even sharper when they were supposed to be -- not like any tube gear I've ever heard.

Now for the million dollar question: was the tone or harmonic body there in that way that I so enjoyed with a single-driver SET amp?  A resounding "yes"! drums now sounded like drums with drum heads and body resonances instead of percussive thwacks.  On Jerry Garcia and David Grisman's Shady Grove CD, Jerry's guitar has a very real woody tone now and Grisman's mando not only sounds like a mando, but a classic Gibson mando.  Across the board, at all ends of the spectrum from cymbals and mute trumpet to ddouble bass and tympany, it was all there and all good.  Not artificially bloated in the mids, with no discernable noise, and all the dynamics anybody could want plus something else... that one last thing... that quality of dimensionality that only tubes can bring.  I had found it and it was good.

I took out the stock tubes and rolled in a NOS military grade 1950s Genalex (made by Mullard) rectifier, a rrarely used but highly musical 12FQ7 in the buffer stage (which can only be done if you have had the modifications done), and a brand spanking new 1955 CBS/Hytron 8514e (12au7 equivalent) in the gain stage.  When I first listened to this combination it sounded slow and muddy and very dark.  I had heard the hytrons sounded closed in and slow for a while but much better after a day or two of play, and sure enough, a couple of days with this holy trinity of tubes in the preamp I had finally arrived.

Now, should this sound like a raving review of the modded Minimax preamp, well, it sort of is, but the real point of all this is that without an amplifier that can do absolutely everything the source signal demands of it, the best sources and preamps in the world won't get you any further than the amp will let you go, and the Signature 70s deliver!  They deliver it all, with no strain, no hint of holding back, and no sign that anything can push them to the breaking point (of course every amp has it's limitss and common sense should be exercised), and all this without a hint of hum, hiss, or any other nasties to ruin the effects.

I now know that the Signature 70s are going nowhere, nor will be the little giant of a preamp, and even though I now know that the sound I'm experiencing is the best that I've ever had, it's only going to get better with improved sources, power delivery and perhaps that Response Audio EXtreme makeover for my Adagios.  Now I'm confident that I can hear any subtle changes anywhere in the system, and that has not always been the case.

Looking back, I really am at a loss to explain this, but as I mentioned earlier, the only thing that makes any sense at this point is some sort of impedance mismatch, non-linear reactive losses in the signal path from the source to the speakers, etc., but whatever it was, when the drive of a tube preamp that is apparently adding no perceptible noise, preserving detail and dynamics, and adding a dimensional richness was introduced in the system, it really showed off everything the Signature 70s are capable of -- which is a faithful representation of the sum of the upstream components feeding it, and in my case an 89dB, 2-way transmission line speaker as the load.

So, 4 weeks ago I was seriously pondering selling my Signature 70s, and now you'd have to pry them from my dead body if you want them, and all because a small, affordable, capable preamp was able to deliver what the amps have been wanting all along.

Do I need to say that this is my ears, my tastes, my room, my speakers, etc., and that YMMV, but I am now firmly in that growing camp of believers who think the pairing of a good tube front end with digital amplification is as close to audio heaven that I'm going to get.

Vinnie, thanks for hanging in there with me, !  When it comes to my music, I'm generally a pretty hard customer to please, but given my financial limitations I'm driven to find the most for my money that I can possibly afford, and now I don't know that even if I had all the money that one could want, that I would change this setup -- it does everything I need, and does it beautifully.

Best,

Jim

[-Richard-]

Hi Jim ~

It is always wonderful to read your posts... I think you have really found something quite
extraordinary here.

I am deeply grateful to you for posting your impressions... always articulate, well thought out
and deeply insightful.

I feel that you and I have a similar auditory aesthetic... so I am counting my pennies to see
if I can spring for the Minimax preamplifier... I want to hear what you are hearing.

Thanks again, Jim, for sharing your audio journey with us... Vinnie's new Sig amps are
doing something that is so beguiling that I want to write about it soon... to share with
everyone what I am hearing... however the Signature 70's still need more burn-in to
"come into full song" as the Brits sometimes say.

Please share any other thoughts you may have with us, Jim... I read everything you write
with the greatest interest.

Warm Regards ~ Richard

[kbuzz3]

What a post !!!! I think im going to break out some of my tube pre amps for my sig 30!!! I think the joule electra may be perfect

If a post can inspire, its a great one

[miklorsmith]

Great story!

I'm running my Signatures through a Lamm LL2 Deluxe.  It is an absolutely beguiling combination.  It is highly reminiscent of the Yamamoto 45 SET sound I enjoy.  Without upstream tube conditioning, I'd give the nod to the Yamamoto nine times out of ten.  With the Lamm in the system, it's very close.

The Sigs are very smooth but do not create the harmonic content of tubes.  Put some upstream and it's a different conversation altogether.

[jrebman]

Well, thank you all for the responses.  I'm not even sure what I should or could say at this point, but I do want to acknowledge the compliments.

In truth all of you have been part of my journey, whether you know it or not, and that's why forums like this are as valuable as they are.

The preamp continues to improve and Bill said it will take a good 300 hours or more before it settles in, so that will be interesting when it gets there.  I honestly feel like I have found my way to a great combination.  How? I have no idea but trial-and-error, sprinkled with a bit of intuition and plain dumb luck, and of course the subjective reports of others who share the passion and ferreting ou t the ones that resonate with me.

I've made plenty of mistakes along the way, spent many an hour in indecisive fretting, changed my mind, only to change it back a day later, and in general demonstrate any number of other qualities of the disease, but things are really beginning to gel, my tastes maturing, and really, the music is truly starting to take center stage and the equipment falling into the shadows -- I said "starting" .  There are still gear decisions to make, and I'm sure some of them will need rethinking, but the bottom line is that I'm really enjoying the music now, and that's as it should be.

When I want to get philosophical and ask why the audio hobby is so appealing to me, I have to think that the answer lies somewhere between the ability to exercise both halves of my brain, the emotional and healing aspects of the music so beautifully presented, and in my deepest self, the fact that it is a substitute for a lost physical sense that I had depended on to supply my most immediate and palpable connection to the world around me.  Music hath charms...

-- Jim

[kbuzz3]

stupid question but i can find my instx manua. How does one wire up a sig 30 for use with a pre amp? 

[lonewolfny42]

stupid question but i can find my instx manua. How does one wire up a sig 30 for use with a pre amp? 

Simple....you plug in the preamp output IC's into the top inputs on the Sig. 30....rear 30 photo..
Then set the amp volume...say half way....and adjust your preamp volume to where you like it.

Jim....
Glad to read you stuck with your 70's...plain or flavored with tubes... it works....

                                Chris

[Vinnie R.]

Now, should this sound like a raving review of the modded Minimax preamp, well, it sort of is, but the real point of all this is that without an amplifier that can do absolutely everything the source signal demands of it, the best sources and preamps in the world won't get you any further than the amp will let you go, and the Signature 70s deliver!  They deliver it all, with no strain, no hint of holding back, and no sign that anything can push them to the breaking point (of course every amp has it's limitss and common sense should be exercised), and all this without a hint of hum, hiss, or any other nasties to ruin the effects.

I now know that the Signature 70s are going nowhere, nor will be the little giant of a preamp, and even though I now know that the sound I'm experiencing is the best that I've ever had, it's only going to get better with improved sources, power delivery and perhaps that Response Audio EXtreme makeover for my Adagios.  Now I'm confident that I can hear any subtle changes anywhere in the system, and that has not always been the case.

Hi Jim,

Great post!  I am very glad that you decided to try out a tubed preamp in front of your Sig 70s... based on our discussions it sounded like a good fit for what you were looking for.  Thanks for posting feedback about Bill's EE premap.  I'd love to hear one for myself one day 

stupid question but i can find my instx manua. How does one wire up a sig 30 for use with a pre amp? 

Hi kbuzz3,

Chris is correct!  If you were to set the Sig 30s volume to max, you'll probably have too much gain and the music will get loud too early on your preamp's volume control.  Set the Sig 30s volume attenuator to a position that you find allows you to get the most useable range out of your preamp.  Just think of the Sig 30s DACT stepped attenuator as a gain control for the amp, and once you dial in the gain, use your preamp's volume control.  This will give you the most control, and lowest SNR.


All,

So as you can see from Sabe's original post all the way down to Jim's, the question of "to use an active preamp or not to use an active preamp?" has no correct answer.  It really all boils down to the rest of your system (source, speakers, room acoustics, etc) and your taste in sound. 

With certain warmer sources (e.g. NOS dacs, iMod, etc.) and speaker combos, you might find that a tube preamp adds too much coloration and/or noise and takes away from the music.  In other cases, such as Jim's set-up, a good tube preamp adds "good stuff" to the music and is a pleasure to have in the system. 

I think it's great to have you guys post your personal experiences here for the benefit of everyone... it is much appreciated! 

Have a great weekend,

Vinnie

[jrebman]

Thank *you* Vinnie!  Today I just pushed the whole system further than it has ever been before... I really cranked it up and gave the NY Rave disk a play from start to finish.  Wow, and it truly didn't even blink -- not the amp, not the speakers, nothing.  Sure wish I had an accessible VU meter, but suffice it to say it was very loud -- much louder than I would normally play, but I wanted to see what would happen under some more extreme conditions.  There was no hint of clipping or distortion, and the speakers remained totally controlled and glare free.  Never, and I mean never, heard anything like it in my house.  Wonderful!

Yes, it really is all about synergy, and I certainly hope nobody was interpreting this as me telling them what to do, or that if they don't have a preamp, they are missing ut.  It's about synergy and personal taste and finding what trips your trigger.  I found, at least the foundation (and then some) to finish building the remainder of the system on -- squeezebox, turntable, and all the associated options and tweaks implied with those.  Ok, now it's fun again, and I think that's about the best place to be with all these things audio.

Thanks again,

Jim

[Vinnie R.]

Hi Jim,

Awesome... Glad everything is working out and you are having fun and enjoying your system! 

Thanks again for posting,

Vinnie

[jrebman]

And then... today I just had to go and put a NOS Mullard 12AU7 in the gain position in the preamp... OMG!

Sorry, no more words.

-- Jim

[Sigfreed]

Hi Jim-

I also am using a EE Minimax in front of my Sig 30's and love this combo.I was wondering if you had the chance to try an aftermarket power cord on that Minimax?
I am using a VH Audio Flavor 4 with gold wattgates.This cord is pretty reasonably priced and can be found used occasionally for an even better price.I got better sound out of all of my gear using this cord.I use it on my source as well as on my preamp, sub and line filter.I was a healthy skeptic of aftermarket powercords until i delved.They have certainly delivered in my system. Brand new the cord needed to definitely get some hours on it(at least 10) before i started hearing the magic.He offers a 60 day money back guarantee on them so for me it was worth the try.I kept that cord and then ordered more along the way as funds allowed.
I am loving my Sig 30 and it is almost right there with my Wright 3.5's(SET) in alot of ways and in some ways even better.I keep thinking i am going to go back to the Wrights's to listen to that again and compare but i can't get myself to yank the Sig 30 out of there to do that.I started a thread on here "Sig 30 compelled" if you would like to read more about my journey. It's been great and i have become a huge fan of both the EEM and Sig 30 for sure now! ENJOY! 

[jrebman]

Sigfreed,

It is really a nice pairing.  Did you by any chance have yours modded by Bill's engineer friend?  I don't know what the stock one sounds like, but this one is dead quiet, unbelievably dynamic, and allows you to use the 12FQ7 or 6414 in the buffer (middle) tube position, which really seems to bring a great sound to the system as a whole.  The NOS mullard I put in yesterday made such an amazing change that I listened to it for about 6 or 7 CDs straight through.  The soundstage opened wide, wide, wide, and deep, deep, deep, there was much more body in the lower mids and upper bass that the reverbations of the studio or performance space really came to life, drums, acoustic guitars, cellos, upright bass, all sounded so full and real that it was just scary, and then there were the vocals -- clean and clear like I never heard them before.

Anyway, to the subject of power cords, they are definitely on my list, but I'm a little cash poor right now with my wedding coming up in two months, so they will have to wait.  Hmmm, wonder if audio dealers have wedding gift registers .  I'd actually like to get a pair of Black Sand Violets for my squeezebox PSU and the minimax, but as I said, that will have to wait.

Thanks for letting me know about how your pairing of the Sig amp and the Minimax pre is working out, I have to say that this combination is one that I will be holding onto for a long time -- and anybody who knows me, knows that is quite a statement .  The Sig 70s, the Minimax and the Adagios seem to complement each other so well you 'd think they were all designed and voiced together -- synergy in spades.  Finally!

-- Jim

[nicksgem10s]

Hi Jim,

I have been following your journey with the Sig 70s because I am on a very similar one with mine.

I have been using them in my system for several months now and have used several different speakers and have not had a preamp in the system. 

I run them direct with my Consonance CD120 that has been modified into an incredible digital source.  I recently made a huge upgrade in my speakers to Salk Sound HT3.   

I can't believe that the Sig 70s can drive the HT3 speakers in my system without a preamp but they can and they sound incredible.

I did however have the opportunity to hear the Sig 70s paired with the new Audio by Van Alstine Ultra SL tube preamp (20db gain).  The extra gain was welcome with the Ultra SL in the system as the Salk HT3 is a pretty difficult speaker to drive to its full potential (at least with 30 watts).

I am broke right now after the speaker upgrade so I am not using a preamp at this point in time.

I am however going to be trying out a Burson Buffer in my system to see if the impedance matching from my source to amps and the added 6db gain give me the boost I am looking for.

Vinnie's amps are amazing.  Do you know of any other 30 watt amps that can drive speakers like this?  His power supply and design is incredible.   

I will post more when I have something new to add.

Thanks for sharing your experience and I will be sure to do the same.

Nick