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mike m
 
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Default Help--Dynaco MK3's

Hello All
Help!
I'm going nuts trying to get My MK to work properly have 2 identical
Dynaco MK3's. Completely rebuilt 6 months ago and both worked
beautifully. Went on vacation for 10 days, came back Sunday night turned
on the system and heard almost nothing from the right channel(amp#2).
Switched connections first to see if it was a source problem. Problem
follows Amp #2 . swapped 6an8's, swapped 5ar4's swapped kt-88's. Problem
follows amp #2

Unit #1 works perfectly.clean sound to max. gain. Unit #2 has a very
week output and as gain is increased the sound becomes louder and more
distorted.
I have been comparing both units A to B
Both units have identical voltages at all test points within 5% of each
other.
Both units have been completely rebuilt with all new caps and resistors.
All speaker connections are now with banana plugs.
I have checked every value of caps and resistors on unit 2 and all are
correct. I have checked all solder connections at least a dozen times,
including putting a hot iron to every joint. I have checked for any
touching wires, contacts etc. I have gone over the unit 3 times now on 3
separate days.

I checked the feed back circuit and all values are correct.
What am I not seeing?
Any suggestions?
Thank you in advance
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Mike Mueller