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previous: anonymous Sorry, I was holding a crying baby ... -- 8/17/1999 12:55 AM

Re: Update suggestions for Tube Amp FAQ?

8/17/1999 1:12 AM
R.G.	Re: Update suggestions for Tube Amp FAQ? Ah. OK, got it. That advice originated with my reading of Russell O. Hamm's paper, "Tubes vs Transistors Is There A Difference?". In this paper he notes that he found that substantially all the tonal differences in tubes and transistors occurs in the first 12db of overdrive. Having read that, I posted an opinion that to make a smooth overdrive/distortion device, you could deliberately limit yourself to the 12db overdrive per stage and put in multiple stages of no more than 12db per stage to maintain the softness of overdrive even if you accumulate huge amounts of overdrive in several stages. This would keep harshness from accumulating. This trick should keep the "tubiness" of the sound even in a massive gain device. I've tried this with an iterated CMOS clipper, limiting overdrive to only 6db per stage. It makes for a sustain-forever sound with an even tone at almost any signal level, but without the harshness of a massively clipped stage. I'm sure that I'm not the only one smart enough to see that possibility, and it might have been someone else that you read as well, but I think we both got it at the same place.

8/17/1999 1:12 AM

R.G.

Re: Update suggestions for Tube Amp FAQ?

Ah. OK, got it. That advice originated with my reading of Russell O. Hamm's paper, "Tubes vs Transistors Is There A Difference?". In this paper he notes that he found that substantially all the tonal differences in tubes and transistors occurs in the first 12db of overdrive.

Having read that, I posted an opinion that to make a smooth overdrive/distortion device, you could deliberately limit yourself to the 12db overdrive per stage and put in multiple stages of no more than 12db per stage to maintain the softness of overdrive even if you accumulate huge amounts of overdrive in several stages. This would keep harshness from accumulating. This trick should keep the "tubiness" of the sound even in a massive gain device.

I've tried this with an iterated CMOS clipper, limiting overdrive to only 6db per stage. It makes for a sustain-forever sound with an even tone at almost any signal level, but without the harshness of a massively clipped stage.

I'm sure that I'm not the only one smart enough to see that possibility, and it might have been someone else that you read as well, but I think we both got it at the same place.

Replies:

hys how about how to pick a o/t & p/t f... -- 8/17/1999 7:14 PM
GFR Accumulated soft overdrive -- 8/20/1999 12:36 PM