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Old 6th June 2002, 01:52 PM   #11
SteveG is offline SteveG  United States
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Join Date: Jan 2002
Location: Newton Falls, Ohio
I will agree that feedback has it's place... as someone already said, it's a good tool to put a GOOD design over the edge. But, at the same time, I think the appeal of tubes (besides their distortion characteristics) is the fact that you can get the job done with very few gain stages, and while the distortion is relatively high compared with solid state designs, it is of low order, and is not irritating or harsh. NFB, it seems to me, is a subtractive process. I say that you should build gain as linearly as possible with as few components in the signal path as possible, and then if you have some left over it may be alright to try some NFB. It could put it over the edge. Looking at the numbers, is it really worth it to put a design that is making .5% distortion at typical average listening levels into the .0X% range? I'm not convinced that the cure isn't more harmful than the disease, in a case like this. Distortion on the peaks seems fairly natural to me- our ears produce it. As long as it is clean on average, and the order is low and the amount fairly low on peaks, I don't see the problem with it. Also, if we have efficient speakers, it seems fairly simple to keep the amp in a low distortion area at sane volume levels. Just my .02
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