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For tube sound, which is more important: preamp or power amp?

I have always loved the “tube sound” - warmth, midrange, soundstage. Through the years (since about 1975), I have owned many tube and solid state amps and preamps, in various combinations. Presently, I have a tube amp and a solid state preamp. But like most of you, I am thinking of making changes, again.  Not to cloud the discussion, the specific brands are not important.  I also listen to acoustic music, females vocals, love mini monitors, EL34s, NOS tubes, and don’t care that much about bass.  So you can see that my taste fits the tube sound very well. But I have had systems that are too warm, not enough dynamics or details, and fat in the low end, too.

okay, now to the discussion.  To produce the tube sound, which is more important: the preamp or the power amp?  Let’s talk in general, and (if possible? May not be) not tied to one specific piece/brand/model of equipment.  I know there are exceptions to any general rule.  Not sure if it makes a difference to your comments, but I have no phono and am running line stage only.

As an attempt to prevent the conversation as going in a big tangent, let’s assume equality of price/quality. i.e. not comparing a $10k power amps contribution to a system to that of a $1k preamp.  Let’s also assume that the amp (tube or solid state) can drive the speakers just fine, such that compatibility does not limit the decision. And ignore mono blocks versus stereo amp differences.  

two follow ons: I have  the perception that preamps give you more bang for the buck - meaning that it takes less money to get a great tube preamp compared to a great tube amp.  Agree/disagree? And second, I have never owned a tube dac or CD player, and will assume that tubes in either of these is less critical than in a preamp or power amp. Agree/disagree?

i am interested in your thoughts.

Bill
meiatflask
nugat
38 posts
 
I tested various tube/SS scenarios with my Shiit Freya preamp, SS hypex n-core and Airtight AM201 tube amplifiers and Shiit Yggdrasil DAC. Freya offers three options: passive, FET, tube. For the last position I use 1940's VT231 Tung Sols. Here are my observations for preamp/amp combinations. Since I don't hear  meaningful differences between passive and FET positions of Freya, I'll just use "passive" here.

Passive+AM201-- good "tube" sound combo 
TungSol+AM201-- too much of the good thing. Euphony blurs detail.
Passive+ncore  -- maximum detail and truth
TungSol+ncore -- less detail more euphonic. I use it for jazz with female  vocals. The voices become a bit "sunny and smiley".

In practice I use the last two positions for the convenience of switching Freya only and no need of recabling.
 
meiatflask OP
155 posts
 
As the OP, I have thoroughly enjoyed everyone’s comments.  As I expected as I threw the question out there, quite a bit of the discussion is philosophical, and the views are quite different.  And you cannot avoid some of the very practical issues such as speaker needs and tube life/ cost.  

I have avoided the speaker compatibility issues by using relatively efficient mini monitors that are easy to drive, and have a small room where 30 wpc is more than enough.  I know that many of you don’t have this luxury and so your situation is more complicated. 

so, (and knowing that this will not be my final equipment purchase) I think it’s time to buy another tube preamp (replacing my naim ss) to go into my primaluna tube amp.  Rather than bog this thread down with specifics, I’ll probably start another discussion on the merits of a 2-4k preamp versus dropping 8k and making the preamp the most expensive item in my system.

but, continue discussing preamp versus power amp, as it has been great.

Bill
bigkidz
3,404 posts
 
All very good comments above.  It comes down to what tube sound you are looking for IMO.  To me building components my DHT DAC provided more of the tone, dimensionality, soundstage, micro to macro dynamic swings then either my DHT preamp or tube power amp.  So my experience may be quite different than others.  My DAC was recently purchased by another Agon member and he has a Dude tube preamp, with NuForce mono block amplifiers.  His Dude provided beautiful tube sound in his system with a SS DAC.  Inserting a DHT DAC added space, dimension, tonality, micro to macro dynamic swings, more separation of vocals and instruments, depth, etc. to the sound.  DHT is a different type of tube sound that is not lush like the old CJ gear.  Different tubes provide different sound to the system, 6922/6DJ8, EL34, 300B, 6SN7, 101D, etc.  To me DHT is more like SS meets tubes type of sound.  Which is the best bang for the buck is another evaluation.  I recently modified a CJ MV-50 power amp.  These amps can be purchased used for not too much money.  It had some damage so I rewired the amp to all point-to-point wirings and added a few upgrades to caps and resistors.  The amp in stock for IMO is a basic good tube amp.  After the upgrade it was a wonderful sounding tube amp.  So in general which is the best bang for the buck, that comes down to the design and your ears.  I cannot say one does more than the other IMO.  I hope this was somewhat helpful.


soundsrealaudio's avatar
soundsrealaudio
756 posts
 
If it were me I would go for a good tube amp. One that is not fat sounding. That can also be caused by the tube amp / speaker combo. so make sure that the work well with each other. 

So now that you are there you can try some different preamplifiers, both tube and solid state and find out which one you prefer. 
soundsrealaudio's avatar
soundsrealaudio
756 posts
 
I have been chastised for not indicating that I am a dealer and I just forgot to do that. Sorry. 
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