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Help! Adcom ACE-515: Anyone been inside?

The big Adcom power amps are well known for taking out their power switches or whatever other switch is used to control them.I have changed many.

Between the huge toroidal power transformer (toroids have much higher turn-on surges than conventional power transformers) and the equally huge filter capacitors,there aren't a lot of switches or relays that can survive the abuse.

On my own 555,after replacing the power switch (for which I had a hard time finding the correct physical size) I also installed a relay (had a spare) used for switching heat-pump compressors.Now,the switch only controls the relay,which should last longer than me:)

An inrush current limiter would have also been a good idea..........laziness,the mother of prevention....
 
Sounds like my relays should have burnt up long ago. Picked up a second 515 off ebay so i can spread my amp load between them. Ill rebuild them both using your parts list JKent (Thanks).
Assuming the Nichicons are polarized, are they clearly marked ?
Ive done very little circuit board work, but im sure i can do this with a little help from you guys.
 
Could i trouble you for the part numbers for the Nichicon caps you used? I see several possibilities on Mousers website, and equivalents are not listed in the repair manual.
Why did you choose to replace only these 5 caps? By my count there are 14 of them.
Hmmm.... it seems they want most caps replaced with "identical factory part" for hazard reasons. ??
 
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I just received a used ACE515 bought on ebay. It is in great shape and was built in 1996. It is fully 10 years newer than my original 1986 ACE515, which worked flawlessly until last week. The only parts that are the same are the case, relays and plugs.
JKents parts list is no good for the later units as the circuit board is not the same. Relays are the same though !
Makes me wonder about the ACE615, which i cannot find anywhere !
 
There are only a few caps in there so a couple of clear photos before removing the old caps should be good if you have any doubts as to how things go back together.
I really like my 515. It's running the original relays as well but seems to work just fine. I figure it either didn't get much use or was possibly used with a smaller amp for most of it's life.
 
I have had two of these for decades, both purchased used. Both working perfectly until a power outage followed by several abrupt turn-ons and turn-off of power. I have two surge protectors, one in each electrical panel, after loosing a TV, modem, HDMI input, etc, to a power surge early in our occupancy of the new house. In this case, the Adcom in operation at the time stuck in the "on" position where everything plugged in stayed powered on. Basically I had to train my wife how to turn on both the Crown pre-amp and the JBL/Urei power amp in the "Library" room where the TV is. I left it this way for some time while shopping for another ACE-515. Gave up when I saw how much people were asking for examples that looked to have been in a war zone.

So today I took the system apart to pull the ACE-515 and see if I could find anything wrong. Nothing visual. Continuity tested as it should, so I hooked it up with the case still open and everything was working as intended. I'm guessing the relays just had to unload somehow after the trauma. It's now back in the cabinet and working as it always has. This one is one of the later (1999) Chinese-made models with the round power button. The one in the main system has the infamous Adcom rocker switch and is made in USA. Since everything is triggered by the pre-amp, the rocker is never touched.

I like the way these work as sequencers and looked hard to find something as affordable that used a 110v trigger but everything seems to use 12v these days. The older one switches two Crown PS-series amps which have their own delay, but it used to trigger two Crown D-series amps which did not—the reason I wanted the Adcom ACE in the first place. Now I just love it for the simplicity of how the rest of the family turns the system on by turning on the pre-amp. Great little units, both working perfectly again.
 
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