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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
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
yogiboy's avatar
yogiboy
5,891 posts
 
Call the manufacturer of the preamp and ask if you can replace with a lower gain tube. I do this on my tube phono preamp with no problem!
tooblue
1,997 posts
 
@gochurchgo, you need to just leave that Quicksilver alone and let it break in till you get a couple hundred hours + on it. The builder is very conscious of the tubes he uses and the matching of them. Enjoy the music.
kalali's avatar
kalali
1,977 posts
 
You didn't mention what signal tubes you have in the preamp but if you have 12AX7 tubes you could switch to 12AT7 or even 12AU7 tubes which have lower gains, respectively. 
gochurchgo OP
931 posts
 
This has nothing to do with the preamp I just bought. There was a discussion I had with an acquaintance which is why I ask. It has nothing to do with me personally.

i was asked the question and I said that it seemed to me that by dropping the out put 10db the added volume to make it up might add more of the tube coloration.
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