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Discussion about the Korg PolySix synthesizer

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Mod to make PWM rate have more variation

Mod to make PWM rate have more variation

2013-12-03 by <jim@saltlands.com>

Does it seem possible to replace a specific component in the PWM rate circuit to allow for greater variation control with the PWM rate knob? Would like to have both slower and faster speeds, and have it retained in same memory settings. How would we make the PWM rate cv input more sensitive to the cv it is receiving?

Re: [PolySix] Mod to make PWM rate have more variation

2013-12-03 by Johannes Hausensteiner

C19 on KLM-367 sets the time constant for the LFO. If you increase it
you get a longer charging/discharging cycle (lower MG frequency).
By VR5 the charging current (via OTA IC21) is set. If you cannot adjust
it fast enough you might change R55 to a smaller value.

Johannes


On 03.12.2013 15:40, jim@saltlands.com wrote:
>
>
> Does it seem possible to replace a specific component in the PWM rate
> circuit to allow for greater variation control with the PWM rate knob?
> Would like to have both slower and faster speeds, and have it retained
> in same memory settings. How would we make the PWM rate cv input more
> sensitive to the cv it is receiving?
>
>

Re: [PolySix] Mod to make PWM rate have more variation

2013-12-03 by <jim@saltlands.com>

Thanks! I'll check this out... So this might allow a wider control of speed in both directions in the end?

And this is the LFO for the PWM, yes?

Thanks again. I'll post here when I get past my other tasks first..

Re: [PolySix] Mod to make PWM rate have more variation

2013-12-04 by Johannes Hausensteiner

Sorry this is the LFO for the MG,
PWM is similar, the cap is C32, no variable poti but rather R22.

Johannes

On 03.12.2013 23:11, jim@saltlands.com wrote:
>
>
> Thanks! I'll check this out... So this might allow a wider control of
> speed in both directions in the end?
>
> And this is the LFO for the PWM, yes?
>
> Thanks again. I'll post here when I get past my other tasks first..
>
>
>
>

RE: Mod to make PWM rate have more variation

2013-12-05 by <jim@saltlands.com>

Ok thanks johannes,

So then, what are my options? Can I make the PWM both slower and faster with one mod? Or do I need to just either make it slower or make it faster...

Re: [PolySix] RE: Mod to make PWM rate have more variation

2013-12-05 by Patrick Belcher

Hey, Johannes has pretty generously (as always it seems), given you the necessary info. Try it and find out for yourself!


On Thu, Dec 5, 2013 at 12:01 AM, <jim@saltlands.com> wrote:

Ok thanks johannes,

So then, what are my options? Can I make the PWM both slower and faster with one mod? Or do I need to just either make it slower or make it faster...