[RDavidson]

So I went ahead and bid and won an auction on a Adcom GFA535 which looks to be in very nice shape, on the recommendation from another AC member for my specific application. The amp is only about 4 hours from me, so shipping should be quick and painless. I paid $130 shipped. Not a steal, but not bad either. I greatly considered the overall condition and shipping distance. Reading around, this is a very decent little amp that people enjoy modding.

Anyway. Question:

Is it better to go ahead and have it checked out by a reliable electronics repair shop now, (note the amp is like 25 years old and never been in for repair before) or should I wait until something fails then have it fixed? I assume it is better / possibly cheaper to have it looked at now and get some caps replaced, rather than wait until failure..........or is it? The amp has fuses in it which should minimize damage in any event. I just worry about failure causing damage to speakers hooked up to it, or catastrophic failure of the amp itself = expensive repairs.

Anyone have any thoughts on this? I know the amp is cheap. But it is also apparently well made and I think it'd be cool if it lasted another 20+ years without issue.

[Ericus Rex]

Some Adcom models from that era have leaky electrolytics.  Google will tell you if your model is one of those unfortunates.  The leaky fluid is conductive so waiting and repairing later could result in more repair costs as other components get shorted out.

[RDavidson]

Some Adcom models from that era have leaky electrolytics.  Google will tell you if your model is one of those unfortunates.  The leaky fluid is conductive so waiting and repairing later could result in more repair costs as other components get shorted out.

Thanks Ericus. You always have great info / advice.

[Freo-1]

Definitely get it looked at, just to be safe.  Adcom amps from that era were known to fry speakers, as the DC offset would go haywire, and they do NOT provide any speaker protection.  Once that (and the electrolytic caps) is sorted, it is good sounding amp.

[RDavidson]

Thanks Freo! You and Ericus must be audio brothers from another mother.
It almost always happens : Where I see one of you post something (helpful / useful) the other is soon to also chime in.

[avahifi]

Any time you acquire an older power amplifier have a good shop run it up VERY slowly to normal AC line voltage with an AC variac.

Older big power supply electrolytics "deform" if they are not energized for a long period of time (over a year or so).  If they suddenly see a hard full voltage turn on, this can cause them to fail suddenly.   

Bringing the amp to full line voltage very slowly (over a period of a few hours) can save these lytics and give you more useful service life.

Frank VA

[RDavidson]

Thanks Frank. Though the little Adcom doesn't have huge caps, and I don't have a lot to lose here if the amp blew up, this is still useful info in general.......And I'd rather not blow the little amp up. I intend to get it back up to spec and probably leave it powered on most of the time.
The amp will have an easy life driving small rear speakers (via wireless transmitters) high passed at 110hz in a modest yet cozy home theater system for the foreseeable future.

[Ericus Rex]

Thanks Freo! You and Ericus must be audio brothers from another mother.
It almost always happens : Where I see one of you post something (helpful / useful) the other is soon to also chime in.

That's just because we're both geniuses!     

[mjosef]

I got two of the original 535 purchased back in 1987, one is boxed up for the past 12years, the other one has seen intermittent use the past 8-9 years. I also have an Adcom 555 serving sub duty in my HT system, no problem with either of these amps, so unless they have been abused by previous owner(s) they should be just fine. All has the original power caps.
You can always fire it up with no speakers attached and let it sit for a hour or so to make sure.