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ADCOM GFA-5800 clipping

I just purchased from a friend an ADCOM GFA-5800. Can anyone shed light on why this Adcom GFA-5800 clips even at a moderate volume level? Could there be a problem with its thermal protect sensor? For such an above average rating of 250 watts per channel, why does it clip despite being driven lightly? The problem presents itself consistently after thirty minutes of use at a decent volume level. The amp doesn't even get hot yet it persistently clips(left channel yellow light glows). I've checked all connections, speaker wiring and another power amp hooked up with the same system as the 5800. The other power amp doesn't clip. Any info on this would surely be of great help. Thanks.
monm1670
9 responses Add your response
rleff
1,065 posts
 
Are you hearing a the amp clip as well or only the visual LEDs
lighting up?
monm1670 OP
9 posts
 
Hi Rleff,

The left channel sound suddenly disappears and the orange left channel light glows leaving only the sound on the right ch. I guess the amp itself clips when this happens.
Post removed 
vernneal's avatar
vernneal
438 posts
 
What speakers?? This ,means everything. Gut feeling though is you got ripped off
auxetophone
114 posts
 
Well, if it's a friend, probably he didn't know there was a problem. Anyway, it certainly seems to be broken now.

As a long shot, I'd disconnect everything and make sure there's nothing floating around inside the amp (turn it upside down & see if you hear it rattle), clean all the connections and try again (using your most expendable pair of speakers). But you'll probably be asking for your money back.
koestner
663 posts
 
make sure if you use stranded speaker wire that there isn't one small strand touching another. I have seen this happen and the system will still work, but overheat the amp soon after.
monm1670 OP
9 posts
 
Hi everyone,

It seems the general consensus is that the amp is broke. Anyway, I really haven't paid for this ADCOM GFA-5800 yet. I brought it home to audition. I'll just return it to my friend. Thanks everyone.
monm1670 OP
9 posts
 
Hi Koestner,

I've used another amp to check if something else was wrong aside from the Adcom. The other amp worked and did nor clip at all but the GFA-5800 did almost always clip after thirty minutes or so. I suspect that there's something wrong with the thermal protect circuit. Thanks anyway.
monm1670 OP
9 posts
 
Hi Koestner,

I've used another amp to check if something else was wrong aside from the Adcom. The other amp worked and did not clip at all but the GFA-5800 did almost always clip after thirty minutes or so. I suspect that there's something wrong with the thermal protect circuit. Thanks anyway.
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