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Strange Harmonics From JCM800 (2204)

10/26/1999 4:14 PM
Bob	Strange Harmonics From JCM800 (2204) Hi all, I have a circa-1987 JCM800/2204, and I noticed this morning that it's producing some really oddball low frequency harmonics, several octaves below the notes I'm actually playing. This is most noticible while soloing. The harmonics don't necessarily follow the notes - for instance, I bend a note up, the harmonic drops. Chords are just a big mess. It's hard to tell what it's actually doing sometimes, but it's there and it's driving me nuts. I've swapped in several different pre and power tubes with no luck. Does this sound like a filter cap problem perhaps? Thanks, =Bob

10/26/1999 4:14 PM

Bob

Strange Harmonics From JCM800 (2204)

Hi all,

I have a circa-1987 JCM800/2204, and I noticed this morning that it's producing some really oddball low frequency harmonics, several octaves below the notes I'm actually playing. This is most noticible while soloing. The harmonics don't necessarily follow the notes - for instance, I bend a note up, the harmonic drops. Chords are just a big mess. It's hard to tell what it's actually doing sometimes, but it's there and it's driving me nuts.

I've swapped in several different pre and power tubes with no luck. Does this sound like a filter cap problem perhaps?

Thanks,
=Bob

Replies:

SpeedRacer I think it's IMD. I'm guessing the ... -- 10/26/1999 5:37 PM
Randall Aiken First guess: needs new filter caps.... -- 10/26/1999 5:52 PM