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General question about tube preamps and gain

I have a (possibly moronic) question unrelated to my previous thread. This is a general question about tubes and gain.

So say you buy a tube preamp and it sounds clean and clear. You decide you want that dark, syrupy sound (classic tube sound?). So you buy tubes that impart this sound on the signal and install them.

Now installed, you notice that the more you turn the preamp volume up, the more the tubes impart that sound on the signal. But you can’t play it loud. 
So could you, theoretically, put attenuators (lets say -10db) between said preamp and the power amp to lower the output signal which you’d then turn the volume up and drive the tubes a little harder to impart more of the tube’s sound at lower levels?

I hope this makes sense. It does in my head but that don’t mean much.


gochurchgo
gochurchgo OP
931 posts
 
@tooblue  do you find that driving the tubes harder adds to the sound?

the 3B was a preamp I was looking at on the used market after glowing reviews and good words on forums about it.
audioman58's avatar
audioman58
4,389 posts
 
The gain of the amplifier has a direct correlation to the output of the preamp, if an amplifier especially a solid state amp ,Has too much gain it can impact also a higher noise floor 
I have seen this a lot with direct heated Triode preampsIt depends on direct or indirect tube circuit , there are many factors
tubes also , you didnot mention what types of tubes 
for example a 12au7 ,and a lower gain 5963 variant may be warmer sounding 
but have 15% less gain , you just have to turn the volume up a bit 
more to get the same spl levels , any time you add a another Attenuator or something in the signal path less sonic purity ultimately.
gregdude
222 posts
 
It couldn't hurt to try your idea. Does the power amp have adjustable sensitivity?  Lowering that would also be an option. 
tooblue
2,004 posts
 
To answer your question, I am not sure that I am driving the tubes harder, just that with the attenuation I am getting more into the sweet spot of the volume controls. Both the pres I have seem to have benifited greatly with attenuation employed, please note both these pres have dual stepped volume controls, with that said as you add volume each step seems to be smaller allowing for closer adjustment. Hopefully someone will jump in with a better explanation than I am able to provide. Both these pres have been used with the same amps with the same results, VTL MB125s, Pass XA30.5, Canary CA306 and Quick Silver M120s all needed the attenuation.
gochurchgo OP
931 posts
 
While this question isn’t about my preamp
specifically, I’ll play devil’s advocate and use it for reference.

Lets say the preamp comes stock with 12AT7 JJ’s.
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