[sdiy] Ms20 filter clone PBC?

[Magnus Danielson]

From: "JH." <jhaible at debitel.net>
Subject: Re: [sdiy] Ms20 filter clone PBC?
Date: Wed, 27 Feb 2008 20:47:28 +0100
Message-ID: <000b01c87979$9672f8a0$0400a8c0 at jhsilent>

> >Just out of curiosity, why does it say "LP/HP slopes are -12dB/oct" ?  In
> >the actual MS-20 it looks like the HP is -6 dB/Oct, since the output is
> >taken from the same stage as the input.  Tim Stinchcomb pointed this out
> >some time age in his detailed analysis. Is the MOTM module configured
> >differently?
> 
> You're right.
> It's a 2-pole filter that can be re-configured as LPF and HPF and some crude 
> Notch mode.
> In HP-Mode the slope is 6dB/oct (yet resonant), just like the original MS-20 
> filter.

Then it is a 2-pole filter with either LP -12 dB/oct or a HP +6 db/oct
responses and controlled Q on pole-pair.

Cheers,
Magnus