2. amps-preamps
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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

Showing 1 response by elliottbnewcombjr

elliottbnewcombjr
5,249 posts
 
I've never experienced what you describe in any of the tube equipment I ever used.

Perhaps the volume control needs a bath in contact cleaner.

If cut the signal strength anywhere, between preamp and amp, and I personally would want remote control of that and easy removal of it.

Loudness Compensation. Old tube preamps and receivers had Fletcher Munson Loudness Compensation circuits, whereby frequencies were progressively adjusted for equalization at lower volumes.

Have your friend look for this feature and enable/disable it, perhaps it is involved in the differences heard.

https://en.wikipedia.org/wiki/Equal-loudness_contour
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