Importance of line stage pre--Who Knew?


Well, I'm sure a lot of you knew, or there would be no $5K and up market for line stages.

As for me... This month marks the 40th anniversary of buying my first stereo with my own money. In all that time I've only had solid state in the signal chain except for a Jolida phono preamp and matching line stage I picked up a couple of years ago. It turns out that the tubes in those units were for a buffer stage to warm up the sound, while the gain was handled by op amps. Well, recently an audio buddy came by to spin some vinyl and show me a tube-driven line stage preamp he wanted to sell.

See it here.

This is just a simple, modest line stage preamp with 5-input rotary selection knob, balance, and volume. Five pairs of inputs, one fixed and two volume-controlled pairs of outputs on the back. However, it's a PTP hand-wired design with tube rectifier and large transformer. I didn't want to like it as it had a couple of deal-killers: 1) no remote control and 2) too tall to fit on my audio rack thanks to that outsize transformer. It would have to be a game-changer for me to consider getting it.

We tried it out in the humblest of circumstances. I set it on a Rubbermaid step stool in front of my rack and patched it into the signal path, bypassing the Jolida op amp/tube buffer line stage.

HOLY MOLY!

Game changer? Sh'yeah! After just a few seconds of hearing it you know it's not leaving the house. So what did it do?

It simply sounded more real and less electronic. It heightened the illusion of performers in real space making music. It took my system a big step away from a tune player to a sonic virtual reality device. Sonically the difference might be considered subtle, but in the realm of emotional response to the music, it was a big step. There was more separation between the various elements of the mix, and if you sat in the sweet spot between the speakers, you heard a 3-dimensional image of performers spread out before you. That physical separation also separates into audible separation. It was easier to hear how the musicians interact with each other to make music together--just like in a live performance. Instead of an amorphous left-to-right smear there was a sonic hologram of where the performers stood in the mix. However, this did not desconstruct the performance, but rather showed how the elements worked together to form ensemble music.

Timbres sounded more real: Brass had more blat when called for, more sense of air flowing through metal, of lungs full of air providing the energy for the resulting sound. Strings sounded pluckier, voices more human, acoustic instruments woodier... you get the picture. It made LPs sound enveloping with a nicely laid-out soundstage, and it elevated computer-based digital music from tolerable to involving and enjoyable, again with the 3-D imaging and wider-than-the-speakers sound stage.

Before picking up this piece, I was thinking of upgrading amplifiers yet another time. But I experienced a valuable lesson I had previously known more in theory--that for fine gradations of amplitude, tubes rule, and it's the low level--preamp and component level--signals that are most fragile; if part of the signal drops out at that stage, no amplifier will bring it back regardless of the amp's bandwidth, rise time, signal-to-noise ratio, or resolving power. The preamp has to caress and amplify those low level signals and pass them on to the amplifier so you can groove to them when they exit the speakers. Since all my sources--LP, CD, FM, iPod, and computer--run through this unit, everything sounds better,

In fact, one of the things I learned from this experience is that my $220 used 1981 Heathkit amplifier is even better than I thought. Paired with this preamp, it is still superb. Sure there are better and much better. But for now and some time to come, it'll do nicely.

Since picking it up I swapped in a set of Sylvania NOS tubes--a JAN (mil-spec) 6X5WGT rectifier (smoother delivery and better voltage regulation) and a matched set of '50s-era Sylvania 6SN7GTB triodes (even more liquidity, less grain, more 3-D imaging). I'm a happy man. Next up--sell off some electronics and get a tube phono stage from this maker.
johnnyb53

11-04-12: Peter_s
Maybe you can figure out a way to add a motorized volume control to it?
To my surprise the lack of remote became a non-issue.So far, with this unit I don't miss the remote control. With all my previous SS preamps and integrated amps I constantly fiddled with the remote's volume--turning it up to hear loud passages and down when crescendos might wake the house or simply irritate me.

However, the noise floor on this preamp is so low that I can hear soft passages just fine and the crescendos, while loud, don't get hard or bright. From this new experience, I'm theorizing that if you constantly fiddle with your volume control, it *may* indicate that your line stage lacks low amplitude resolution. With the new preamp, I keep the volume knob at one position and just let the music play on. This is a complete paradigm shift for me and it profoundly enhances my listening experience.
Johhnyb53 I know just what you mean. Good for you. I just put a Joule Electra LA100 mkII preamp in my system a few days ago. It's not my first quality tube preamp; I once had the top of the line Cary preamp in a different system. The JE preamp has made everything in my system sound more like real instruments and music. It has brought dimension, depth and realism. It is a "game changer" that has brought the "high end" experience to my system. As a jazz lover, I'm very happy with what this tube line stage brings to the music.
Jhonnyb53,
Congratulations!Getting rid of OP-Amps and their associated negative feedback was a wise move. This new found realism,life- like flesh and blood presence and emotional connection is an eye(ear) opener once discovered.Well implemented simple circuits with tube amplication seem to do this the best.Passive and solid state have`nt been able to match this realism and involvement you describe in my experiences(so far, maybe one day). I certaintainly can understand your increased joy and happiness.
Regards,
The thing that can be frustrating about this hobby is the old adage, you don't know what you don't know until you know. I guess that is why most of us are constantly experimenting.
JohnnyB53,

I just had an experience like that myself this past week. I had been using my Dac as a Pre/Dac and bought a Dared tube preamp from a buddy and the second I hooked it up my wife said WOW!!! (So did I) It sounded like we walked into the IMAX as sounds instantly had fire breathing life with power, presence & colors! Now, I can't say I did not know this was going to happen but I had gone so long with out a preamp I guess I kinda forgot what a huge difference it makes. Now I am looking to tube roll myself and make it even better.
Telescope trade,
I`m just curious,what was your reasoning for going without a seperate preamp initially?
Regards,
Hi Charles,

I had sold my last pre & amp awhile back and went to an integrated amp for a bit, then sold it and bought a pair of Newforce Ref 9's and hooked it up to my Pre/Dac (Emotiva XDA) and said "good enough" and just left it like that. Then I decided I wanted to add some tubes somewhere, and the preamp made the most sense so I got the Dared and that's how it happened.
Johnnyb53,

A well designed tube line stage can make a world of difference, plus you
can roll those 6SN7'S for flavor.

I got a TRL 6SN7 preamp a couple years back, in less than 5 seconds of
play I knew it would not leave the system.
I have a really refined system, one that I've made countless improvements in from power delivery to chassis tuning to optimization of cabling...

It's really interesting because I have two systems and one uses a tube amp and preamp while the other uses an all-digital electronics chain. They both use power regenerators and similar cabling and both sound outrageously good.

That being said, in my view the all-digital system has the edge in dynamics and transient speed and it also sounds the most natural or realistic if your reference is live acoustic instruments including the human voice.

I have a truly excellent dual-mono 6SN7 tube line stage that I can instantly switch in and out of the all-digital system between the digital preamp and digital power amp and in the past, with certain combinations of cabling and AC filtering products it has made a marginal improvement in smoothness and musicality over a direct Balanced XLR connection. Although the improvement of the 6SN7 pre was small, I thought it worth having.

But recently, I added the PS Audio P3 Power Plant, Mojo Audio AC power cords on the preamp and amp, and the Wyred 4 Sound C2 Balanced XLR interconnects between the preamp and power amp. I did this in individual steps and each time I inserted a different piece, starting with the PS P3 Power Plant and adding in the different power cords and finally the interconnects and found there was an improvement in musicality, inner detailing and musical bloom.

In my recent comparisons between the direct XLR connection and the tube line amp connection there is less of a difference and in fact the XLR connection offers slightly better dynamic punch and clarity with the same level of musicality. So at this point I'm thinking of removing the tube buffer entirely.

I still love my tube system for its great musicality and smoothness but for true musical realism I favor my evolved all-digital chain.

I think tubes provide smoothness in systems that have other problems that need to be masked. But once you eliminate the problems that cause grain and harshness, really good digital or solid-state electronics can provide a musical experience that is as good or even better than tubes. And I can listen to this system at a very healthy volume for hours without any listener fatigue.

My main problems with tubes (besides the inevitable tube rolling) is their treble and bass roll off at the extremes, their slight rounding of fast transients, and their inevitably higher noise floor. This translates into a smooth and musical but more muddled and less resolving musical presentation that can be had from the best solid-state or digital gear IMHO. YMMY, and I realize that many folks prefer a sweet, relaxing presentation that loses some detail and articulation in the process.
...a bit of a caveat......most changes (subtle, grand, good, bad) are perceived as a "Wow". Live with this new one for a few weeks and discover ITS warts...you just might want to go back to your old one.
I don't think so Stringreen. I've been in this hobby 40 years and have been a reviewer for over 15 years so I have a lot of experience with such things.

All I know is that as my Mojo Audio power cords continue to break in, the sound is getting incrementally better and better. In fact, I have never heard digital high frequencies sound so much like the real thing!

I'm not sure I understand what you mean about going back to my "old one." My old one of what? If you mean the tube pre it's easily switched in and out. And incidentally, the tube pre usually works better with my turntable source because the highs are a bit more extended with the vinyl source and the tube pre knocks that down just a touch. But I need to try it again because I haven't played the turntable since I installed the new W4S XLR interconnects on Friday.

BTW, I'm from Tucson so if you ever get the urge to take a day trip it might be worth your while...

Frank ;-)
I respect plato`s opinion and he`s right YMMV.I`ve found the complete opposite result.High quality tube components(preamp and power amplifiers) are more resolving,honest,realistic and nuanced.They seem to be purer with audio signal propagation. They are capable of preserving the musical signal and allow that vital emotional connection and expression of music.Thus far in my personal experience SS/digital amplified signals just are incomplete and stripped of the inner detail subtle information,just does`nt sound as real life as high quality tube electronics.For some reason this observation does`nt hold up with source components(CD and DACs so far, gube vs SS),I don`t no why.
Just another man`s point of view. I know preference can go in either direction.I hear less masking and superior resolution with the tube gear.This is why they sound more natural and less HiFi character compared to SS/digital amplifying the signal,at least to my ears.The good thing is we all eventually find our own audio direction and solution. Johnnyb53`s revelation makes sense to me. I don`t believe he`d have quite this same reaction without 'good' tube components.There`ll always be two sides to this story.
Regards,
If the OP actually listed his system it would give a better context to understand his recent aural discoveries.

I also think Stringreen makes a good point.
With all due respect, Charles1dad from your reply my feeling is that you've just never heard digital or solid-state done right.

But here is a possible explanation. With solid-state gear those who don't like it normally feel this way because of its sins of commission... This means that since ss amps and preamps are generally lower-noise and more linear through the audible range that you can hear more of what is going wrong in the treble if you don't use proper cabling, chassis diffusion, or AC conditioning/regeneration products.

With tubes, the sins are mainly of omission meaning that they generally roll treble, round fast transients, and muddle things a bit in even the best designs. This makes the sound more "musical" at the expense of removing musical information, nuance and detail.

And honestly, I've done these experiments enough times to be confident in my position. The outcome is always the same.

I absolutely love both my digital and my tube systems. They are both glorious. But I know the digital system is more nuanced and revealing while at the same time seeming more like a live musical experience.

By contrast, the tube system sounds extremely smooth and euphonic. It has a huge holographic sound stage and the music is so sweet and soothing it can literally lull me to sleep. But ultimately I don't think it's as musically correct.

As I said, both systems sound great in their own right. I just think the digital format has more potential to take me closer to a "Live" performance. But everything has to be right and optimized for this to happen and I've taken pains to do this right.

With tube gear it's easy because as I said the sins are of omission rather than commission and you gain more by the tubes removing high-frequency nasties and rounding transients than you lose in bass control, proper transient reproduction and lower noise.

Obviously many tube fanatics won't agree with me but it's mostly because they haven't had the same success getting their solid-state or digital gear to sound right... because it's more difficult to achieve and you need to really understand the things that work and the things that don't.
This a really good thread. I hope a lot of people take the time to read it. A good preamp makes a huge difference. Unfortunately, most people overlook the preamp and go for the more "exciting" components like amps and speakers. Thats a huge mistake. When you get the right preamp, its like a window opens up in your system.
There are simply too many variables to be able to make definitive generalizations about tubes and solid state or analog and digital. No doubt a lot of it has to do with implementation, cabling, vibration isolation and other tweaks, especially those addressing room acoustics. And whether CDs are just off the shelf and untreated, for example.
With tubes, the sins are mainly of omission meaning that they generally roll treble, round fast transients, and muddle things a bit in even the best designs. This makes the sound more "musical" at the expense of removing musical information, nuance and detail.

Having had both solid state and tube systems I just cannot agree with this as it pertains to the best designs, which regardless of price point, I will say are few and far between. I especially find this comment erroneous as it pertains to direct coupled and OTL designs that have been properly executed.

As for your statement on solid state, the part pertaining to chassis diffusion, cabling, and AC/power regeneration says it all...and I say that with all kindness because I just can't stop shaking my head. If that is what it takes to get solid state to sound its best, then maybe those designs should not be considered "the best" and need to be revisited.
I have always said that a tube preamp is the most important component in a system. I realize that is a controversial statement; a good source is very important too. I found I need the gain and dynamics of an active pre for listening satisfaction. I have two Joule Electras btw, which have replaced much higher priced preamps; just more musical in my system and for my tastes.
I feel the same as Clio09.Plato I respect your opinion but realize we`re just not going to agree and that`s okay.
Don`t make an assumption on what me and other posters here have heard or experienced just because our conclusions differ from yours. You have two systems and find the digital one more correct, I can`t argue with what you hear,that`s personal.I stated my reasons for preferring tube amplification you don`t have to share the same opinion. Don`t comment on my exposure(or lack of), you have no idea what it consisted of.

Over the years I`ve listened to many tube and SS based systems(and digital) and have formed my own conclusions also.It`s pointless to turn this into a which is ultimately better. Both approaches will have plenty of supporters. Let us just agree we`ve both found our respective paths to satisfying systems.
Regards,
Okay, ClioO9, You're right, we are not going to agree. But I want to make a couple of points. First, yes, perhaps direct-coupled OTL amps are a little less muddled than other types (I have owned the Atma-sphere M60 Mk3.1's btw as well as highly-modified AHT/Acoustat direct-drive OTL amps), but conventional OTL's like the Atma-sphere's throw an amazing amount of heat which is not great in AZ in the Summer. But beyond that, they are a crap-shoot as far as their bass-performance goes because of the usual bass impedance peak at some audible low frequency. I had a problem with that.

Second, my idea of using chassis diffusing feet on my gear applies equally (if not more) to tube gear, not just digital and solid-state. I take it from your remarks about power regeneration that you are poo-pooing it, which I find very suspect in view of the sonic improvements regeneration provides. But I won't argue further with you because I see no point in it due to your close-minded attitude.

Charles1dad, you're right, I don't know the full scope of your experience but without me tooting my own horn I would just say that the odds are (being a past president of the NJ Audio Society, a veteran Senior Reviewer and 40-year audiophile) that I have more experience tweaking different types of products and systems than you do. Without a resume of your experience I haven't a clue.

I'll also allow that you and others may take the "tubes are great" view, and I basically agree, I just think there are other approaches that can equal or exceed the limits of tube technology based on my own first-hand experience (not other's opinions or hearsay). Sorry to be a progressive thinker, I guess.
Plato, not necessarily poo-pooing power regeneration (I tried these products in my system so I do not consider myself close minded on the subject) but just your comment and the idea that this, along with cabling and chassis diffusion, is what is required to get the most from solid state. If you need all that then IMO something is wrong elsewhere in the system.

As for the Atma-Sphere your point on the heat and AZ is well taken. However I live in Las Vegas and have managed to tolerate the situation. In may case I look at it as an opportunity to have a built in sauna. Martini and iPad in hand, some good music, and sweat off a couple pounds in the process :)

11-04-12: Stringreen
...a bit of a caveat......most changes (subtle, grand, good, bad) are perceived as a "Wow". Live with this new one for a few weeks and discover ITS warts...you just might want to go back to your old one.
This ain't my first rodeo. I bought my first stereo 40 years ago. I worked in high end audio retail for a year soon after. I've had a lifetime of swapping and comparing components, cables, and now tubes. I *know* what to listen for regarding long term musical involvement and emotional satisfaction.

There's no way the Jolida JD5T 10dB gain line stage can touch this MAGI PTP-wired line stage. I also have 15 years experience swapping current production Russian, Czech, and Chinese tubes against NOS GE, Philips, RCA, Raytheon, and Sylvania tubes, some JAN versions and some not. The NOS tubes--even up to '80s production Philips JAN 12AX7WAs--are consistently quieter, smoother, and more durable.

To those who wondered, my current setup is a Technics SL1210 M5G (has the factory tonearm rewire) w/KAB fluid damper, an Oracle sorbothane mat, tonearm wrap, LpGear ZuPreme headshell, Audio Technica AT150MLX. The turntable is platformed on a combination of brass cones, Vibrapod cones and pucks, a very heavy 3-1/2" thick maple butcher block cutting board supported by silicone gel pads. This feeds a Jolida JD9A phono stage with NOS Sylvania 5751 Gold tubes with Herbies tube dampers, with the unit sitting on Vibrapods. This formerly fed a Jolida JD5T line stage but is now feeding a MAGI all tube line stage to an unbelievable 1981 Heathkit AA-1600 power amp (about 180 wpc) powering a pair of Mirage OMD-15 floorstanders assisted by a pair of Mirage MM8 subs.
I agree with Plato in my experience of 47 yrs. Tubes are fantastic and have their place. But when I want to get more of the music- the rhythm, flow, needed dynamics, timbre, the picture of the whole package. A more natural balance of what I would remember as the real thing as being there, as reasonably best as we can produce it via our sound systems. The ss stuff I have more often does that for me.To me there is music and there is sound. You can walk down a street and here live music coming from a closed up home. I can't explain it but it definitely is different than reproduced sound/music. To me it is easy to tell and for me I get it most, most of the time from my ss stuff. I have not had but only a few high quality tube amps, pre amps and I have been around a few more. They were all more expensive than my ss stuff. I know I haven't tried every option we have a audiophiles. I have only optimized them for about 10 of my 47 years so it might not be a perfect comparison. But that is my reasonable conclusion for me.
ClioO9, okay, fair enough, but ALL the tweaks I've mentioned (cables, chassis diffusion, and AC conditioning) make positive improvements in EVERY system and on nearly every product I've experimented with. But I can agree that most product offerings have room for improvement.

I suggest you go over to PS Audio's website and read Paul McGowan's blogs on the new PowerBase product he's developing. To me this makes a lot of sense... based on my own trials and tribulations. Mike VanEvers used to offer a wood-block resonance tuning kit that I've found quite useful and instructive in my own experiments.

Frank
I'll admit VansEvers was on to something with the resonance tuning using wood. Somewhere I still have his paper on the various types of wood and their resonance frequencies. His power block was one of the very few conditioning units I liked. Wish he was still making products.

Tried the PS Audio regenerators in the past and didn't like them. However, I will take a look at the newer technology being developed. If it looks interesting I will give it a try. One thing I do like is their trial period.
Clio09 I definitely like the new P3 Power Plant in my digital system. In my smaller tube system I use a Monarchy Audio P100 (sounds really sweet but has low power output) to power my digital sources with great results. Keep in mind you don't want to kill the chassis vibrations... just redistribute them to other nodes by using other materials for diffusion. This (wood blocks and other feet) works on just about every component I've tried it on.

Paul McGowan's development of his new as yet unreleased PowerBase is accessible under "Paul's Posts", which is a continuing saga that he e-mails out on a daily basis for those who sign up. The story begins here: http://www.pstracks.com/pauls-posts/beginning/8708/

And you can track that backwards to the present day's post to see how it developed and where it went. This is actually fascinating... to me at least. Frank :-)
I have found that eliminating my Quicksilver line stage removed a slight haze , images were sharpened, dynamics improved. I am using Audiokinesis Prizmas (94db efficient). I am driving a JAS Array 2.1 (amp section only) directly with my DB audiolabs DAC using the dithering control in Pure Music as a volume control. I have tons of gain, better dynamics/transparency. I hear no downside, preamp is now for sale. YMMV
This thread was about the insertion of a quality tube preamplifier and its affects on the sound of the system. It seems somewhere along the way it turned into a tubes vs solid state battle.
With tubes, the sins are mainly of omission meaning that they generally roll treble, round fast transients, and muddle things a bit in even the best designs. This makes the sound more "musical" at the expense of removing musical information, nuance and detail.

This statement is utterly false in every respect. Tubes can have bandwidth in preamps that is as wide as the best transistors- we get 400KHz out of our line stages. I imagine some tube circuits might do as suggested (its tricky to get wide bandwidth out of 12AX7s for example). But there is a reason that color TVs could be made with tubes in teh 1950s and that is because the tubes themselves have plenty of bandwidth (you need lots of bandwidth to build analog video circuits).

Additionally if anything I find the transistor circuits to be the ones lacking detail, not tubes, generally speaking. However transistors do make more odd ordered harmonics (which is the source of their oft-perceived brightness) which some might come to interpret as greater detail if that commission is slight. However I find that quite often what is happening is brightness is masquerading as detail- when you get detail and a relaxed presentation (read: able to listen to it all day and all night without fatigue) together at the same time then you are on to something.
11-05-12: Foster_9
This thread was about the insertion of a quality tube preamplifier and its affects on the sound of the system. It seems somewhere along the way it turned into a tubes vs solid state battle.
Usually does when someone makes a rediculous statement about one or the other
I don`t believe the OP`s post was ridiculous at all. He was simply happy with the improved sound via the addition of his tube linestage.It`s his opinion.I don`t understand why some feel compelled to tout 'my non tube approach is better' as it`s irrelevant to the original topic.If you prefer non tubes, great, start your own thread.
Regards,
11-05-12: Charles1dad
I don`t believe the OP`s post was ridiculous at all.
I wasn't referring to the OP.
When people post things that imply one topology sounds better to some people because it "masks other issues" (IOW - You don't know what good sound sounds like), or the ever popular "You've never heard what I like done right" (IOW - You don't know what good sound sounds like) it is inevitable.
As the OP I can say that putting *this* line stage in *my* system improved it in every way. I do like what tubes do in resolvving microdynamics at the low line level, but I've also heard SS units do impressive things at that level, particularly the Marantz Reference series that uses their proprietary HDAM gain modules.

The other factor is that although this unit flies under the radar and I was able to get a used one for $500, if I compare its features and build quality with the current market, it's equivalent to an overachieving $2500 unit such as one might get from Rogers, Rogue, or PrimaLuna. A SS unit at that price would also outperform the $299 (now $550) Jolida unit it replaced.
Plato,

"11-04-12: Plato
ClioO9, okay, fair enough, but ALL the tweaks I've mentioned (cables, chassis diffusion, and AC conditioning) make positive improvements in EVERY system and on nearly every product I've experimented with. But I can agree that most product offerings have room for improvement."

Can you clarify that one? I understand that you are only talking about systems that you've worked with and not every system out there. But are you saying that any of the tweaks that you mention always works well or did you have to try a few different ones until you got the right match. Just to clarify, if you tried 10 different interconnects, did all 10 sound better, or did just certain one(s) make a better difference? So even if not everything you tried worked well, you always managed to come up with something?

For me, most of the time I can find some kind of tweak that works, but not always. I have yet to find a cable that sounds better than the stock cords on my Ayre amps.
Foster 9,

"11-05-12: Foster_9
This thread was about the insertion of a quality tube preamplifier and its affects on the sound of the system. It seems somewhere along the way it turned into a tubes vs solid state battle."

I can't believe I didn't see that. I thought the OP's post was great, and on a topic that is hugely overlooked; I just missed it. To clarify, anything that I said in my other posts was referring to SS as well, and not just tubes. I love tubes but I do believe that SS has come a long way and is worth consideration.
W3ux,

I understand what you are saying in reference to your Quicksilver. Their preamps are not in the same league as their amps. They have a very "classic" sound to them. I wouldn't be so fast to dismiss tube preamps in general, though. There are plenty of other tube preamps that are much more revealing and modern sounding. If you have the opportunity to demo some other units, I think you might change your mind.

11-05-12: Schubert
Makes me feel better, only took me 10yrs to figure a tube pre was better.

Oh, I had my suspicions that a tube pre would be a better thing for several years, but between young kids around the house and the much higher price of good tube gear I just didn't pursue it. But I'm glad I finally did. It's not like I didn't enjoy my music before; I just enjoy it that much more now.
Abucktwoeighty, having gone from a solid state preamp to the tubed preamp I have now, I can only say that the musical realism has really stepped up.
I would also need to phono pre, as I'm currently running the McCormack with a built in phono stage. Haven't started looking seriously yet, just figuring what I may need and how much I would like to spend. Had to make another financial decision recently that put thoughts of system changes on the back burner for now...
Zd542 - The person that started this thread said he was using a modest line stage, the Quicksilver line stage I was using the latest model and is quite a good performer. Any device inserted in the signal path will impart a sonic signature, no matter how good. If your computer source is as good as you can afford(I'm using a Mac Mini with pure music) and has adequate gain, a preamp is not necessary, you will lose detail and transparancy. You need efficient speakers ( I'm using horns )and proper matching to the DAC for this to work properly

11-08-12: W3ux
Zd542 - The person that started this thread said he was using a modest line stage,
I'm the OP and when I said it was a "modest" line stage I meant that it was very simply built, no gilded tube cage, no Italian styling, no 1/4" thick face plate, no ceramic/polymer hybrid footers, no remote control. However, as far as features that count sonically--excellent circuit design, rugged components, PTP wiring, oversize transformer and tube rectification, ceramic sockets, high quality panel-mounted RCA plugs--it has a build quality to rival line stages up to at least $2500 and maybe $4000.

If your computer source is as good as you can afford(I'm using a Mac Mini with pure music) and has adequate gain, a preamp is not necessary, you will lose detail and transparency.

Yet somehow this line stage is able to caress very low level signals and amplify them intact, and do no damage to high treble signals, such that everything I run through it sounds better, whether sourced from CD player, phono preamp (from turntable) or my Audirvana-driven iTunes.

You do have a point though; the guy I bought it from is replacing it with a transformer-driven passive preamp. Rather than attenuating via variable resistor values it's handled by a multiple-tapped transformer to provide the attenuation while preserving--and even enhancing--signal strength.

My power amp has attenuators for each channel, so I *could* plug into it directly, but the attenuators are on the back panel and I'd have to shut off the amp, wait 20 seconds, and then manually change interconnects every time I wanted to switch sources. Having the right line stage instead is easily worth it to me.
Unexpectedly fixing the bottleneck in your system for $500 makes for a super day. I know I - and probably a lot of others - have had that transformational improvement going from a bad to a good preamp.
W3ux,

I didn't mean to suggest that your preamp, or anyone else's, for that matter, is not good. Quicksilver makes great products. I think the V4's were one of the best sounding amps I've ever herd. I only meant to say that while their preamps are very good, you can spend more money on other products, and get more of the "audiophile" characteristics some people want. More detail, better imaging, dynamic contrast, are all things that can improve as you go up. I didn't mean to offend in any way.

There was mention of using a passive preamp/line stage by some of the other posters. Whoever it was that brought them up, I'm with you. If you don't have a lot of money to go for a really good active preamp, I wouldn't hesitate to get one. You can get truly excellent results with a passive. There are a lot of people who have tried them and didn't like the results, though. I think a lot of that has to do with the source. Since there is no gain on a passive, the job of amplifying the signal is on your sources. If you are using a cheap, mass market CD player, for example, it probably won't sound good because of because of the poor output sections in those types of products. If you have a better CD player with a good output stage, that should eliminate any problems.