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Adcom GFA 555 Power Switch (Rocker Switch)

N

Nanapull

New Member
Hi, all. Does anyone know where I can get a replacement power switch for an Adcom GFA 555 other than Adcom? They want $30 for one, and it's just not worth that much to me to replace it. (It's getting a little flaky, but I can leave it on and switch it off via the power source if I need to.)

Many thanks in advance!
 
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The 555 was designed by Nelson Pass himself. Damn nice amp, but I kinda like the 555 II, which included a DC servo.

If you haven't already, do recap the input board. They are known for leaky caps, and a contaminated board is a bitch to get clean again.
 
Hi guys. Can I confirm that we need a DTDT?
That is what the given parts express part number is showing in 2022 but it has been 15 years. Time flies. I think this is a
DPST. Thanks a million. Cheers from Maine.
 
When I replaced the power switch on my 555 MKI I also installed a heavy duty contactor, as I didn't have a lot of faith in the long-term life prospects of the available switches.
This model is for a heat pump, but any high current relay would be fine. The switch now only runs the contactor coil, and the contactor does all of the heavy lifting. Should last longer than me:)

DSCF2911.JPG DSCF2910.JPG
 
I don't believe Adcoms had surge protection (probably for better sound). I just restored an Adcom GFA-2 with a seized in the "on" position power switch. I upgraded the power supply capacitors from 10,000uf to 12,000uf X 4 and new power switch from Digi Key is 16 amp I think the original was rated at 5 amps? I hope the new switch will last. Important thing is to measure the rectangular cut out dimensions to make sure it will fit. For some reason Mouser did not have a search category for cut out dimension so purchased from Digi Key.
 
Speaking of Adcom, rather than a new thread. I think this is that 80s deteriorated glue gunk that has gone conductive, it doesn't look like leaking caps. This spot is near the heat sources with those 2 transistors right there, so it has accelerated the process I think.

Anyone have experience getting this crud off?

Nice amp, btw. Power sw has no sound other than something introduced thru contamination or corrosion distortion, but it should feel correct.

20220429-081726.jpg
 
idf.bts said:
Speaking of Adcom, rather than a new thread. I think this is that 80s deteriorated glue gunk that has gone conductive
Click to expand...

IMHO you (and this thread) would be better served by starting a new thread, but your identification is spot on.

You can find dozens and dozens of experience stories by googling for "DSBG" (Dreaded Sony-Bond Glue) with site:audiokarma.org. Don't worry if the stories aren't about Adcom - there's little brand specificity to these situations.
 
chazix said:
IMHO you (and this thread) would be better served by starting a new thread, but your identification is spot on.

You can find dozens and dozens of experience stories by googling for "DSBG" (Dreaded Sony-Bond Glue) with site:audiokarma.org. Don't worry if the stories aren't about Adcom - there's little brand specificity to these situations.
Click to expand...

If it turns into an endeavor, I will start a thread. I've seen the bottom of ovens that look better so this looks like it is going to really suck.
 
Just a heads up...I purchased the CARLING part # RGSCC901-R-B-B-E and it does not fit my GFA555. It is too big to fit into the faceplate without modification. Just didn't want anyone else to make the same mistake.
 
Please share a pic of your 555’s faceplate. I’ve used this switch without a problem. It goes in nice and tight.

You might have an older version of the 555.


Cheers,
Luis
 
Here's a pic of the faceplate..maybe it is a different model.
 

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Yes, that is an older and somewhat rare version, before they changed to the typical ribbed faceplate. Sorry about the confusion.

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