My mk2 had this awful sounding noise when the 1 meg ohm pot that adjusts the noise VCA level was adjusted improperly. When it was cranked down to 150k the background noise went away. This is VR3 and it's near IC2, Q5 and C23. It adjusts the feedback loop for the M5223 noise gain op-amp. You are right about the filter affecting the sound as the noise generator feeds into the filter on pin-7. This may not be the problem but it's a good place to start.
Fran
--- In korgpolyex@yahoogroups.com, "fugasiyokonda" <fugasiyokonda@...> wrote:
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> Ok so just trying out the new mk2 and aswell as zero fx section the synths got this horrible low level digital noise that stays on relative to the envelopes and seems to be after the filter ? filter does effect it.Is this a know issue ? the poly 800 is kind of unusable.....pretty depressing as it was sold as fully working ......
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