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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
tomcy6's avatar
tomcy6
2,579 posts
 
For $9500 list you can buy a pair of Carver 350 watt amps with a 10 year warranty and Bob claims the tubes will last 50 years:
http://www.bobcarvercorp.com/350wattsamps

" The DC restorer circuit, an exclusive to Bob Carver designs, keeps the output tubes running cool, prolonging their life to beyond 50 years! Prior to the advent of this feature in Bob’s amplifiers, other amplifiers operated their vacuum tubes at a very high idle power in order to keep the distortion low, frequency response extended, as well as for a host of other reasons, related to amplifier performance. And they still do. The downside of doing so is that the tube life is drastically shortened, about three to six years at the most. Worse yet, tube performance begins to deteriorate as soon as the amp is turned on, gradually (and insidiously) robbing the listener of sonic pleasure. In addition to extended tube life, thanks to this invention, there is also no need to purchase expensive matched tubes for the Raven 350."

Now I know there are Bob Carver haters out there, but let’s try to keep to the facts. From those who should know, are these claims realistic?
wolf_garcia
6,683 posts
 
I think if a tube is on, it's wearing out…I'd like to see what at atmasphere says about this.
axememan's avatar
axememan
279 posts
 
If a tube is glowing my understanding is it is wearing out.
testpilot
912 posts
 
If a tube is glowing my understanding is it is wearing out.
Yes, it is wearing out in the same manner that car engine is wearing out when left to idle.
axememan's avatar
axememan
279 posts
 
If the Tube is driving a signal then the Tube will wear more compared to it glowing with the just the heater filament being lit up while waiting for the signal.
.The powering on and off does cause some stress to the tube from the Hot/Cold part of that process.I know people with Guitar amps that have NEVER changed a Tube yet..after years of use.
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