Discussion about the Korg PolySix synthesizer

Hi!

Chip here, the one from the synthhacker blog that you referenced. To answer your questions:

Re: R166 (the 1K resistor not being present), I just looked in my synth...mine is also missing. Interesting.

Re: R167 (the 33K resistor maybe not being 33K), mine is colored orange-orange-orange, which is 33K, as specified. When I measure it in-circuit with my DMM, it is only indicating 4K or so. Since the color bands clearly indicate 33K, the lower reading must be because the in-circuit measurement includes parallel paths through ground or something. Your own evaluation of R167 might be seeing the same effect. What were the color stripes on R167?

Re: R168 (you didn't ask, but it the 22K that the 33K is jumping around), my R168 is red-red-orange, which suggests 22K as indicated on the schematic, but it is only reading ~5K in-circuit. So, again, in-circuit measurements can be funny.

If you've been checking out my frequency-response mods, don't miss the others that I did after this one:

Bypass the Post-Effect VCF to open up the sound: http://synthhacker.blogspot.com/2013/07/polysix-bypassing-post-effects-vcf.html

Deeper Bass (Based on Tony's Discussion): http://synthhacker.blogspot.com/2013/08/polysix-deeper-bass-bypass-c61.html and be sure to read it's follow-up posts.

Flatten Treble Response: http://synthhacker.blogspot.com/2013/08/polysix-flatten-treble-response.html

Good luck!

Chip