Adcom GFA-555 fuse stuck



Hi there,

I've got an Adcom GFA-555, which I use with a pair of Infinity Kappa 8 speakers.

I was running pretty loud on some low frequencies, and I lost all power from the amp. I figure the Kappas were just drawing too much current, since the woofers can dip down to around 1 ohm with low frequencies.

The power light doesn't turn on, so it shouldn't be thermal shutdown or the transistor fuses. I opened up to check, and they are all fine (I put in 4.5 amp fuses instead of the 6 amp ones spec'd to give me a little safety room). After cooldown it still won't turn on.

I didn't see any scorched components either, but I know from personal experience that that doesn't necessarily mean that there aren't any burned out components. I don't smell anything, at least.

So I'm pretty sure the problem is that the power fuse is blown. The problem is, the screw-in plastic holder is cracked in a couple of places, making normal extraction with a screwdriver impossible.

I thought about trying to super glue it, but I doubt that would hold (and I don't have any on hand any way). I suppose I could epoxy an old screwdriver on to it...

I'm pretty stumped as to what to do - I generally tackle this kind of stuff myself, although at this point I know I need a replacement holder in addition to the fuse anyway.

My only thought is to take it to a general electronics repair shop - there's no real audio repair shops in town AFAIK, and the nearest Adcom authorized repair shop is an hour and a half drive away. As long as it's just the fuze, it shouldn't be that difficult of a job - which is why I'd like to do it myself if possible.
blackbeardben
I know you found a simple solution to your problem already, but since the internet's eternal, I thought it best to include this information here for the next guy searching.

From Adcom's website:

"Parts are available form ADCOM's parts distributor Affiliated Electronics. Contact them as follows:
Affiliated Electronics
216 Route 206, Suite 15
Hillsborough, NJ 08844
PH: 908-874-3799
email: teve21@datanyc.com"

Regards all.
Cool, that's good to know in case I ever have any trouble in the future. To be honest, I'm kind of looking at getting a pair of GFA-565s or maybe a Mac sometime in the future.

Unfortunately, I've had more trouble with the Carver (actually, now I have three of the same - picked up one for just $80 from the local used music store). I inadvertently shorted one of them causing one of the channels to go out (replacing the fuze didn't fix it), and something went wrong with one of the others too (I can't remember what it was since I've been in Sweden for graduate school since August.).
I guess I should mention that I've since moved up to a pair of Infinity Renaissance 90 speakers. Wow - what a difference they make (although the Kappas are still excellent).

I had to bi-amp them though - the 555 alone was almost entirely bass-less when powering them. I put one of the Carvers on top, and use the gain controls to match them (about 60-75% of max on the Carvers gets a good balance, which goes to show the incredible current requirements of the woofers).

That (or any potential bigger upgrade is why I'd like to try an even more powerful amp. Maybe a tube amp for the top end, like the ARC amps Infinity used for testing. I of course don't have the money now, being a poor graduate student and all.