preamp vs. no-preamp


Hi guys, I would like to know your opinions regarding the classic question (which also has been posted many times in this forum, I know, I know) whether or not a preamp is needed for a good (= musical sound). You see, if you can delete the preamp and connect the DAC into the poweramp, you can save lots of money, sometimes up to $ 15,000 for a Conrad-Johnson ART (this is off course an extreme example). The money you have spent on the preamp can be used for buying a better source or amplifier (mono's?). So theoretically if you don't have a preamplifier you can improve the sound reproduction by: deleting redundant audio circuitry and interconnect cables, upgrading the quality of you source, poweramplifier or speakers.
My personal experience is that without a preamplifier the sound is becoming thin and uninvolving, but I know there are audiophiles who don't have a preamp in their audio system.
dazzdax
I have talked a lot about this subject in other threads. The inherent problem is that whatever parts ANY CDP is using to control its output/volume is not as good as a the parts in world class preamp that does the same thing.

It's like asking the question as to why should one go with a seperate preamp and amp when an integrated amp does the same thing. Yes I will admit their are world class integrated amps... HOWEVER, a well matched world class amp and preamp will beat a world class integrated amp any day of the week sonically. In this case though, a lot of the reason amp/preamp combo beats integrateds occurs because of isolation issues between low level signals and high level signals.

The problem is that too many CDPs that control volume use a kind of passive preamplification to do this. Basically most of them put out ungodly high outputs at full throttle/volume, and this signal is run through some passive preamplification (usually a type of metal filament technology) that contol it by the .5 db. I used to have a Camelot Uther DAC/digital preamp, and my sound dramatically improved when I moved to an active SF3SE preamp and having the Uther at max output.

KF
My experiences are exactly oppostie of Keith's, I have tried a few pre amps and always found running direct to be better. I in fact did use a CJ Art series I and compared it running direct and both I and the other audiophile listening agreed the CJ colored the sound and lost a LOT of detail/resolution not to mention having a MUCH higher noise floor. I have tried a BAT VK-30se and found there was NO comparison between the two, the passive attenuation of the Capitole was leaps and bounds better. Other pre-amps that friends have tried include- BAT VK-50se, Aesthetix IO signature with dual power supply, Manley Steelhead, Lamm L1 and L2, Edge it just doesn't seem to matter most prefer it run direct. For that matter the best digital playback I have heard ALWAYS uses a passive attenuation of some sort be it in the CD player or an external along the lines of the placette. Any other thoughts on this subject? this really seems unusual that Keith and I would have exact opposite point of views. My only concern that I have right now is I would like more body/weight in my vocals and a slightly larger sound stage- would an active pre help this??? I doubt it- more room treatment, power cords or maybe a new amp is on my docket.
Tireguy, I am not going to claim I am always right. And I have not heard your CDP though I have heard AMAZING things about it. And if you have tried all of those preamps, all I can say is WOWSERS! I wish I were so lucky!

Maybe you have a magical kind of synergy between your CDP and your amp? I am not familiar with either piece.

If you want more body weight and a larger soundstage here is what I suggest getting: Virtual Dynamics Nite AC cord and Nite ICs. The combination is pretty frightening... The only thing I have to say about the Nite AC cord is it just is not fair that AC cords can make as big of a difference as it does in any given system. Especially when put on the Amp and Digital Source. It just is not fair.... The IC's are very good... They may not be absolutely neutral (my verdict is still out on them), but they initially impress me a whole heck of a lot.

KF

KF- If you are not famaliar with Jena Labs and are still searching for the holy grail-in cables- you owe it to yourself to try them. Me, along with everyone else I know who uses these cables feels we are off the upgrade path- yes they are that good! I am skeptic that new cables would help, I am leaning towards pointing the finger at the room/amp. I have heard 5 different Capitole mkII's in different systems and they all seem the same(I surely didn't accomplish all of this comparison at my place :) ran direct, the VK-500 is the cheapest amp that I know anyone is using with a capitole MkII- I don't think I should be bragging about that though!

I am also going try a few PC's before an amp swap, I currently use the Jena Labs 7 strainders and think they are really good but I want to get an Elrod EPS signature 2 and a Shunyata Anaconda on the capitole to see if it will truly give me what I want prior to biting off more then I care to chew :)

It is possible that synergy is the factor at hand- one only knows why our systems all sound so different! Cheers and happy listening ~Tim
I just checkout the Jena Labs website and they look interesting. Both Jena Labs and Virtual Dynamics cryogenically treat their cables. This gives them an edge over most cable companies. Maybe one day I will compare the VD Nite with Jena Labs cables. My verdict is still out on the VD IC's (I just sent a long run to VD for retermination), so I am back to my old Nordost QF... However, I would HIGHLY recommend the VD Nite power cords. Do a search here and AA and the only potential negative comment I have found about these VD Nite cords is their steep retail price ($1500, but can be had for nearly 1/3 on the used market).

The guy I bought mine from was a dealer who was unloading all of his VD cables because he could not compete with VD (due to them selling them directly online). Anyway, his opinion was they were the best he has ever heard, and I wholeheartedly agree with him. He had them in his $100k reference system with top of the line Audio Note gear and Nordost Valhalla speaker cables (he thinks the Valhalla are the best speaker cables he has ever heard, he really wants to find something less expensive that comes close or sounds better than the Valhalla). I am not into the Audio Note sound per se, but it is VERY revealing.

One thing about the VD Nite cables (all of them) require ungodly times to break in (500 hours may not be an unreasonable estimate). Many people I think sell these cables before they have not broken them in sufficiently.

Anyway, I would suggest you try an Ayre K-1x preamp with phono, and get yourself into VINYL! The Ayre K-1x maybe one of the best line level and phono preamps ever made combined. There may be slightly (very slightly) better line level preamps out there (for insane $$$ as opposed to the $9k or so the Ayre sells new). There may be slightly (oh so slightly) better SEPARATE phono preamps out there, BUT no preamp on the planet that I have heard or read about (MAYBE the Supratek Cortese, but this has yet to be determined by my ears), has as good of a line level AND phono section. The K-3x (I have it, is pretty darn great), the K-1x is out of this world.

You will find that vinyl with a K-1x will make your digital well... sound... not-so-good. I am an evil man.

Sorry to take this thread off topic. But I must say Ayre preamplification is worth every penny.

KF
My experience has been the same as TOK2000. I have never had any luck running a cdp direct. Pre-amp does more than just control volume it is really the first level of control in your system. In my system the pre-amp has always had the biggest impact on performance. I could use a mid-fi level amp, high quality pre-amp and get astonishingly good results but if I used a mid-fi level pre-amp, high quality amp I got poor results. Even the audio aero, wadia 861 sounded compressed and lost substantial depth in soundstage running direct. Just my two cents.

Chuck
I agree with Tim, I have always prefered the sound of running the CD player direct, even Wadia. Unless you have the ability to spend a lot of money I don't think you can get better sound with a preamp and CD player than you will get with the Audio Aero Captiole Mk 2. I have tried a Pass Labs preamp on my Capitole and easily prefered the sound of the Capitole run direct.

Tim an Elrod EPS 2 sig might just be the answer to your woes.
I'll stick in the pro preamp camp. Although I don't think I ever went direct from CDP to amp (I've always had too many sources), I did experiment in the early 90's with passive preamps. I didn't care for them overall. They were very revealing, but they did sound thin and bass shy. I've been back on active preamps for over 8 years. I currently use 6 sources, so I need a preamp. I'm sure in the right system a CDP driving the amp straight may sound pretty good, but then how would I play my LP's?

Regards,
John
I threw a Creek passive in my system while the tube preamp is out for repair, and it sounds remarkably good. However, I am missing some body and it is a little thin. Is my preamp worth the price difference? To many it may not be, but to others it would be. I still think a good active preamp is preferable to passive. Frankly, the detail is not that much better than the active.
Every passive preamp I have tried has cut down on both dynamics/microdynamics and resolution/detail. They all tended to put a veil on the music that was not good at all.

One thing about live music is that it is dynamic. If there is one sin I cannot forgive in a component is lack of dynamics. I can forgive something sounding a little more dynamic than it should in certain areas of the frequency spectrum, but lack of dynamics is a pretty big audio sin...

I will say this Saxo, many tube preamps are not the end all in resolution by a long shot. Many solid state preamps are not either. There are not a whole lot of excellent preamps be them tube or SS made.

I must admit that I have not tried some of the state of the art passives of today. Not too many companies make passive preamps to begin with.... This should tell us something about them. Good ideas tend to be copied in the audio world. If a technology works well people will build it and refine it.

I really WANT to know what Capitole uses to regulate volume. If it's regulation is as good as Tireguy says, they should make a preamp with the same technology (maybe they do, I have not done the research).

KF
Passive's are not "preamps". A "passive" is simply a "line level attenuator" that may also function as a "line level switchbox" if it has multiple inputs. While one could argue that it is a technically a "pre-amplifier" because it is before the amplifier, the name "preamplifier" came about as there was a need for amplification prior ( or "pre" ) the final gain stages of a high level amplifier. As such, a "preamp" was "amping the signal prior to the main amp".

Let's get the terminology right, stick to it and use it accordingly. Either that, or you'll all be forced to write a 5000 word essay on the subject. Preamp's have a gain stage : ) Sean
>

PS... Don't get me started about buffered units. All hell would break loose then : )
If a preamp actually amplifies, where on the volume control is zero gain? That would have to be about 5 oclock on the dial, which we never use. So why would we want to amplify a signal just to attenuate it?

I understand that a preamp doesn't actually amplify, rather it optimizes impedences to optimize power transfer. Of course, whether one can hear the difference continues to be the subject of debate (in my mind as well).
Gboren the gain is the constant value on the most of the preamps. There are preamps with variable gain. Turning volume up or down you still working with already amplified signal.
Changing the volume by changing the amp's gain is not efficient and will not sound right.
Remember that all passives are not alike. There are resistive and transformer based passives. There are significant differences in the impedance matching characteristics. The transformer based passives may not exhibit any of the problematic qualities that many of you have experienced in your resistive passives. They should not be "lumped together" because they are very different.
Come on Sean, jeesh, I'm sorry. That's what people were calling them in the very early 90's. Technically, you are correct. However, I will not be submitting a 5000 word essay.

........passive preamp.. whoops I said it again...hehe...buffered unit.....couldn't resist it.

Regards,
John
I'm with TWL on this one- and about to trial the Bentaudio.com transformer-coupled preamp. I have had passives in my rig previously, and agreed on the 'thin' sound, however clarity/detail was very good (sorry Keith, have to disagree with you on that one). However Keith, what I do agree with you on is the lack of dynamic impact across the entire frequency spectrum with passive, and I am hoping the transformer-coupled passive addresses this- should be interesting.

Oh- and Tim- YES to the VD Nite PC's (I use a couple of them- excellent product), but no to the Nite IC's- smooth over too much detail in mine and other reference systems we have tried them in...

Re: the Capitole (I owned MK I for a year and a half, and have heard MK II extensively in my system and others), I agree w TIm- direct seems to be preferable, however the Cap is ultimately not revealing enough for my tastes, and I ended up changing to my current rig which is eminently preferable (albeit more $$)- Spectral SDR 3000SL transport (incredible) and the superb new Audio Note Dac 3.1 Balanced (transformer-coupled) w Kharma Grand Ref digital IC. I am looking forward to testing the merits of the preamp idea once again (am running direct currently, as the tube monoblocks have volume control). I will try to post results on the transformer-coupled pre, as it may be an excellent avenue for some of us...
2 years ago when i had burmester 969 transport,dcs elgar+purcell with aesthetix preamp(amps were komuro,speakers were amatis)i was thinking as TOK20000,i used my system every time with preamp never with elgars volume control and never liked volume control of elgar(it was firts version)good pre-amps is the heart of the system.but now i have CEC tl-omk2 with kondo s ongaku dac connected directly to 2 pair tenor amps with passive volume control on it which drive kharma extended exquisite speakers.
several times i tried very good pre-amps(by-passed volume control of tenor),and every times i prefered without preamp.
my last change now,i m waiting for kondo s new ongaku preamp.
but as many things on audio,passive or active preamps and models are system dependent.
and i think there is just one solution ,is to try...
Sutts, My Bent TVC was shipped out yesterday. John said it should work very well in my system. I am going to try with a Sony xa777es and a krell ksa-250. I have Vmps super tower/R's and also a set of apogee centaur minor's to try it out with. Hope it is everything I have read about it.
Twl has a very good point. It is my belief that the reason that some passsive attenuators sound thin and lacking in dynamics is because they fail to present a high enough input impedance to the source and/or low enough output impedance to the power amp. It's all about impedance matching.
An active preamp can much more easily present a high input impedance and a low output impedance, and should therefore be more system independant.
I have no experience with transformer coupling, but if it solves the impedance problems then I can see how it could be the best of both worlds ... the transparency of a passive attenuator with the impedance matching (and hence the dynamics) of an active preamp.

I'm just too much of a tightwad to try out my theories !
Adsal,congratulation you have the BEST DAC in the world.
What did you have before? M100?

How close the sound compare to the analog ?

Sell your Tenor and buy the Ongaku Fuji !

Good Luck and love to hear your system.
Anyone knows if there is a DIY guide or circuitry for transformer based passive preamp?
I stay with my preamplifier! Poor Dazzdax, I wonder if he is going to count the results of this discussion and then go with the majority...As Tok20000 and Czbbcl I had the same experiences. Connecting my Accuphase directly to my Pass results in a flat non musical sound. Going through my ARC Ref1 preamplifier made the whole difference. I did the same test with a Wadia 861 and an ARC VTM200 and then through an ARC Ref2 preamplifier, same result. Finally, Wadia 861 to Nagra monoblocks directly, then going through the Nagra PL-P preamplifier...same result. In any case, I do not mind to keep testing, after all is part of this vicious hobby. But in my experience has allways been consistent. Going through a good preamp is the best way.

Marakanetz, there is good info at this link

www.bentaudio.com

They have parts, kits, and info on building these passive transformer volume controls.

They also have complete units, with either manual or remote controls.
Gecus- Your experiences are interesting, I would have to agree with the CD players you used. I had an Accuphase DC-300 digital pre and I never cared for the volume control on it- it like the players you tried use a digital volume control, which some claim drops bits. I did not experience bit dropping per se how ever it just never sounded smooth enough it always had that digital edge/glare to it.

Sutts- Thank you for reinforcing me trying that PC, I will have to give them a shot! Hey you never know until you get it into your system.

This is really very helpful, I never realized we were all this split in our opinions on the subject :) I nice friendly disagreement- Happy listening everyone even if you use a pre ;)
audio999
first i will get kondo s ongaku preamp,and i m waiting some news from kondos new amps gakuou 2x30watts with av305 tubes.
before kondo i used weiss and elgar+purcell
regards
Great thread. I am currently running my 9000ES through a pair of Rick Shultz attenuators. The amp. is a Anthem amp2 and Totem Forest speakers. I was looking at the matching anthem pre. or the Adcom 750. After I pay off some of the Cristmass bills.....
Tim
Gboren: You're looking at the subject too narrowly

Not all "preamps" are connected to devices that emit high level signals. There are such things as a phono system, which requires gain prior to being fed to an amplifier. Try running even a high output MM phono cartridge "wide open" into a power amp and see what you hear. Obviously, one needs a LOT of gain in this situation, regardless of the amplifier being used. As such, ANY attenuation of the signal would result in hearing "less than nothing".

As far as line level signals go, some sources simply don't output as much drive as an amplifier may require. This could be due to a weak signal being received from a distant broadcast, very quiet recording ( which applies to tapes, cd's, etc..) or simply due to the fact that the source component itself does not have enough gain in the output stage. As such, additional gain / further amplification may be required prior to feeding the signal into the amplifier to achieve the desired listening levels.

To top this off, some amps offer different levels of input sensitivity. While some amps may roar with as little as 750 millivolts ( .75 volts ) fed into them, others really do need at least 1.5 - 2.0 volts for full output. Since i have seen some sources that put out less than 1.5 volts when driven to capacity via loud recordings, this still may not be enough. For example, the Philips SACD 1000 maxes out at 1.6 volts output in SACD mode when a high level signal is fed into it. On music that does not "roar" and a quiet recording, it is quite possible that you might only have peaks of 500 millivolts to 1 volt available to drive your amp with. For some amps, this would just start to "tickle" them and not really be enough to get their "full fledged attention", hence a lack of volume and squashed dynamics.

All of the above situations would be highlighted even further if using long runs of lossy cable, suffered from signal loss due to poor loading ( impedance problems ), and / or using highly in-efficient speakers.

Having said all of that, i do agree that most of the problems associated with using a "passive" has to do with impedance mismatches and / or weak recordings that aren't strong enough to drive the gain stages of a source component to full output.

If one wanted to avoid such a situation, i'd look for a source ( tuner, DAC, CD Player, etc... ) that was capable of at least several ( 3 - 4 volts ) of output. This should be plenty to drive any amplifer / speaker combo to high listening levels. It would do this without pushing the gain stages of the source into compression, even with a quiet recording. The end result would be no need for a preamp, so long as you only had one line level source that you listened to or didn't mind swapping cables between multiple sources.

Those of us with phono systems, multiple sources and "thirsty" amps / speakers don't mind using an "active gain stage with user selectable inputs" : ) Sean
>
Running my Wadia 860x into a VAC 70/70 MKiii didn't sound as good as using a VTL IT85 (basically a VTL 2.5) with NOS tubes (bugle boys, 7316). The Wadia direct was too bright! Using the pre sound better (full, rich), without sacrificing detail.
I am for with preamp.Flemke by the the adcom 750 is more
tansparent than krell ksl i used to have.I think very
people realize how good is this 750.
sorry to get sidetrack.I have tried theta cd,dac audio
alchemy,and heard wadia,and heard the accuphase $27,000
without preamp,they sound better with preamp,although
if, i dont have the money, i can live listening without
preamp, with this gear especially the accuphase Sacd.
I heard the conrad j ART this gave me the hair raising
experience.
As with everything else in this hobby, it's really about what kind of sound is "preferred" vs which sound is the "best". If you prefer the sound using a preamp, then thats the "best" sound for you. There is no ultimate sound that we will all agree on. It always amazes me that we hear that the goal of hi end is to pass the music from the source to the speakers without adding anything. Yet, if we line up 10 equally expensive components for comparison, each sounds different. Obviously, its not in the best interests of the manufacturers to have all amps sound the same, because our preferences vary so much as individuals. So they intentionally tweak their products for a particular sound that will appeal to a large enough audience, who then declare it to have the "best" sound. Best for them, but not for everyone.
If you have a player that has an analog volume control you are better off without a preamp. If your player has a digital volume control, a preamp may do a better job.
As with everything else in life, it depends. If you go the no preamp route you have to be very careful. The most important factor is now mating the source properly with the amp. Source output impedance and amp input impedance and sensitivity are paramount. The newer transformer based "passive" preamps are the way to go. Impedance matching is accomplished. Once these issues of impedance and sensitivity have been addressed then I believe no preamp is the way to go. With the transformer passives, dynamics and bass frequencies are preserved with the added benefit of the usual gains in transparency that passives are known for.
I'm reviving a VERY old thread to ask a question. What about a cassette deck in between the CD player and amp? Due to my CJ blowing out, I temporarily ran the CD player (an X-Ray, which has no volume control) through my NAK 670zx (which does have an output control), and connected the tape deck to the amp (Classe 15). It actually sounds great (although I do miss the "tube sound"). Plenty of gain and power. I've read about the problems with compatibility and sensitivity, but as I said, there is plenty of power and gain. Is there a problem with this as a temporary setup until I can get my pre-amp fixed? I do not want to hurt my speakers (Vandy 2ce sigs) or my amp. Thoughts?