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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 2 responses by georgehifi

georgehifi's avatar
georgehifi
10,312 posts
 
Call the manufacturer of the preamp and ask if you can replace with a lower gain tube.

Changing a higher gain tube for a lower gain tube won’t do much, you need to change the feedback loop components to reduce the gain, a job for a good tube tech.
One of my tube pre’s has a switch 1 x or 3 x gain https://ibb.co/ygM6WHt

Cheers George
georgehifi's avatar
georgehifi
10,312 posts
 
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?
You will increase the load the tube preamp sees, as then you'll have two parallel loads to ground, and it "may" not be a very good impedance match.
Better off getting the gain reduced in the preamp by a competent tube tech. 

Cheers George
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