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Subject: Re: [motm] News and an OT Polysix request from California

From: "jhaible" <jhaible@...>
Date: 2000-08-10

The only pitfall I can think of is that there are two separate GNDs on
the FX board, which ∗must∗ both be connected to the power supply.

JH.

-----Urspr�ngliche Nachricht-----
Von: The Old Crow <oldcrow@...>
An: <motm@egroups.com>
Gesendet: Montag, 7. August 2000 15:48
Betreff: Re: [motm] News and an OT Polysix request from California


>
> On Fri, 4 Aug 2000, thomas white wrote:
>
> > Request: Old Crow or anyone else who knows...
> >
> > I have an excellent condition effects board from in the Korg polysix
> > and I am thinking about trying to convert it inot a module to get the
> > awesome ensemble effects out of it. Is this possible in your
> > experience and if so, can you help me? I have tried to find the
> > service manual on the web, but the resolution of those I've found is
> > hard to read.
>
> I think JH has already done this, IIRC. I have a couple of spare P6/EFX
> boards that I keep around for doing repairs; I'll have to see about
> placing one into a 1U x 19" rack for general audio use. Offhand it should
> be a fairly easy task.
>
> The board would need a +/-15VDC power source. In my case I would just
> make one from some parts laying around but I'm sure a small Power One
> board (check Jameco, etc) would be perfect for a 1U box. The board would
> need perhaps a small active circuit on the audio input to normalize the
> signal to what the board expects. In a Polysix, the board is fed from the
> VCA summer on the voice board at something like 2.5Vpp (offhand guess,
> would have to dig up schematic to give actual values). Same goes for the
> output circuit, although I think the final output buffer and headphone amp
> are on the KLM-368 so it may just be that they can be wired to some 1/4"
> jacks. The last item is the binary control of the effect mode and the
> control voltage for the effect speed/level setting. All in all I would
> fashion a small PCB that had a power supply, input circuit, out circuit
> (if needed) and control circuit so that hooking up a KLM-368 in a studio
> rackbox boils down to plugging it into the small PCB.
>
> Crow
>
> p.s. I'll document the "Polysix gets a MOTM-410 internally mounted"
> project once the new 410 shows up in the mail. Going to have to get up
> the courage to punch a dozen holes in a Polysix front panel, however...
>
> /∗∗/
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