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Adcom GFA-565 Capacitor Replacement

I own two Adcom GFA-565 mono amps. One began to thump while in use, so I brought both to an authorized service center. Tech tells me that he is finding DC across speaker leads on both amps, and that oversize capacitors need replacing and that he thinks Adcom no longer makes them. I asked for alternatives, he said "they make great anchors". Is there a place I can obtain original or acceptable substitutes for the capacitors? THANKS!
schmengie_mcs7750
gander2's avatar
gander2
2 posts
 
I just bought Adcom GFA-565 monoblocks and they thump the speakers on startup, but after that I'm not finding any problems. Is this a problem that can be fixed? According to Adcom, this is "normal" for these amps (yes I have that in writing). Is this true? And is this different than thumping in use, as noted above? I would like them NOT to thump on my Maggies.
Thanks,
Gary
power_hungry
3 posts
 
I found this article about the amps that really explains the issue with these amps (both the GFA-565 AND the GFA-585) better than any of the posts here:

http://www.jazzfest.tyrell-corp.com/stuff/repair_adcom_gfa-565_gfa-585.htm
strader
1 posts
 
when I change out the leaky electrolytic capacitors between the reference diodes on the driver board, is there a certain type that I want to go to?
you mentioned the reference diodes (6.9 volt temp compensated Zeners) and the bias control transistors (MPS-A63 and MPS-A13 will need to be replaced? any type or part number I should go with for the replacements? thanks a bunch
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