Discussion about the Korg PolySix synthesizer

Did you switch SSM2056 and SSM2044 between voices to see if it may 
lay there ?


--- In PolySix@yahoogroups.com, Niels Ott <niels.ott@...> wrote:
>
> Hello there,
> 
> my Trident MK2 is defective.
> 
> Symptom: VCO 1 is defective for one voice.
> 
> Up to now I was able to found out: Input 1 of IC704 (4x CMOS 
switch) on
> KLM-379 doesn't get the VCO signal on voice 7. On all others it 
does.
> 
> There are some oddities with op amp IC707 but I'm not yet sure. The
> schematics and the circuit board design hint to the direction that 
IC707
> "feeds" IC704.
> 
> The IC707 is a 4558, I assume that it is similar in the Polysix.
> 
> Did anybody of you experience a similar problem? What about 
replacing
> the 4558, did this help?
> 
> Furthermore, some of the 4558s carry a date stamp of 1997 which 
means
> they must have been replaced by an earlier owner.
> 
> Unfortunately there is no shop selling electronic parts in reach so 
I
> can't just go for it and try replacing it. Mail order is an option 
but
> not for a few ICs...
> 
> Thank you for commenting.
> 
> Best,
> 
>   Niels
>