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previous: Dave Balance pot is a 10k. I use a sign... -- 7/29/1999 3:51 PM View Thread

Re: Dumble schem errors - again!

7/30/1999 4:14 PM
Gil Ayan
Re: Dumble schem errors - again!
On 7/29/99 3:51 PM, Dave said:  
"Balance pot is a 10k. I use a signal generator (400Hz) and get about 20v AC at the plates, tweek the pot until they match....I use a 10 turn 2watt cermet pot with excellent results...Dave"
Now, Dave, could you please comment on the tonal differences, if any? I understand that Dumble really did balance the PI plate voltages very carefully in all of his amps. However, and on the other hand, I have played with different plate load resistors in my amps (say 91K and 100K, or 82K and 100K, or 82K and 91K, etc.) and found the tone to be really the same. There are other places in the amp where a little tweak goes a long ways, but this didn't seem -- to me -- to be a place worth spending much effort on.  
But, if it doesn't make much of a difference, I still wonder why Dumble would bother to put a trimmer in there and all.  

Dave I never tried unbalancing the PI...... -- 7/30/1999 4:26 PM