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Alesis RA500 amp - channels crackle, distort, cut out

I have a 15-month old Alesis RA500 amp with a problem - for a few months now, often the left channel would be "crackly" and cut out, but then seem to "warm up" and be fine.  Now, the right channel started to behave like that, even after it had been on for a few hours: it would get crackly and distorted (esp. if fed low-frequency content, like bass guitar) and then cut out entirely.  There's no problem with load; I'm using 6 ohm Polk Audio Model 11 studio monitors (circa 1982 and still some of the best speakers I've ever heard, IMHO).  Note that these behaviors have nothing to do with volume, either - I typically run the amp's controls between 9 and 12 o'clock.
The amp is only about 15 mos old, so I wouldn't think caps are going yet from age, unless they were crappy to start with.

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Re: Alesis RA500 amp - channels crackle, distort, cut out

You have a problem in output stage and output ic need to check or replace.

Posted on Apr 24, 2008

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