Korg 770 Schematic

[Colin Fraser]

The Keio 201012 is diode based (supposedly), and the Korg 35 is transistor
based.
Looking at the 770 schematic it is certainly diode based, but otherwise is
virtually the same as the rest of the miniKorg series, which all used the
201012.
The easiest thing for Korg to have done when they built the 770, assuming
there was some reason they didn't want to make any more hybrid ICs, would
surely be to use the same circuit, with the contents of the hybrid IC in
discrete form.

Colin f


----- Original Message -----
From: "Magnus Danielson" <cfmd at swipnet.se>
To: <colinf at ntlworld.com>
Cc: <RFahl at extensis.com>; <synth-diy at node12b53.a2000.nl>
Sent: Saturday, January 06, 2001 3:03 AM
Subject: Re: Korg 770 Schematic


> From: "Colin Fraser" <colinf at ntlworld.com>
> Subject: Re: Korg 770 Schematic
> Date: Sat, 6 Jan 2001 02:00:29 -0000
>
> Hi!
>
> It just struck my mind that...
>
> > This is interesting - I hadn't looked at this schematic before, but it
> > doesn't appear to use the Keio 201012 IC used by the 700, 700s and 800DV
for
> > the filters.
> > Are the 770 filters a discrete version of the Keio IC ?
>
> But, but... isn't the "Keio 201012" really just the Korg 35?
> Humm... pinning doesn't match too well, but maybe not totally out of
> context.
>
> It seams very feasable that it is something *VERY* similar to the Korg 35.
>
> Oh, BTW... Keio <=> Korg
>
> > Anyone heard them together to notice if there was any sonic difference ?
> > I know the 770 was the last model introduced of the four.
> > Maybe it gives away the secret of the 201012 ?
> > If someone can find a readable schematic that is.
>
> Cheers,
> Magnus
>