Well if you want the CEM sound then clearly only a CEM based filter will do.

I also have a S1mk2 and love its 2/4/6 pole high pass filter. It is voltage compatible with the Doepfer/Eurorack standard - don't keep them apart! I tend to think of the S1mk2 as a giant Euro module instead of a separate system.

People who have used the S1mk2 and the MMF-1 say they sound different FYI. I too assumed they would be the same.

--- In Doepfer_a100@yahoogroups.com , "jakobsweb" <jakob.paulussen@...> wrote:
>
> Thank you for these examples. The Division 6 filter looks interesting but will have a very different sonic character with SSM2040 vs. CEM3320 in A-123 (I have A-105 and A-122 LPs for comparison).
> I have the Cwejman S1 MK2 including the MMF - not sure I want to add it to my Doepfer system.
>
>
> --- In Doepfer_a100@yahoogroups.com , "mirror_saw7778" <haven1@> wrote:
> >
> > The following currently available Eurorack filters have a 4 pole high pass mode.
> >
> > Cwejman MMF-1
> > http://cwejman.net/mmf-1.htm
> >
> > Division 6 Filtare
> > http://www.division-6.com/products/filtare-seiii-eurorack.php
> >
> > there are probably more since there are now at least 42 Eurorack manufactures.
> >
> >
> > --- In Doepfer_a100@yahoogroups.com , "jakobsweb" <jakob.paulussen@> wrote:
> > >
> > > ahh, that's one of the patch examples on Doepfer's A-172 page - the one without audio example. If you could share an audio example of that Thanks for replying to my post.
> > >
> > >
> > > --- In Doepfer_a100@yahoogroups.com , achtung_999 <heinrich.himmelwasser@> wrote:
> > > >
> > > > I totally agree, the A123 is an indispensable tool in my eurorack system. A
> > > > lot of my patches make use of this filter. Very often in tandem with an A122
> > > > and an A172.. Go figure that one out ;-)
> > > >
> > > >
> > > >
> > > >
> > > > On Tue, May 17, 2011 at 11:58 AM, jakobsweb
> > > > <jakob.paulussen@>wrote:
> > > >
> > > > >
> > > > >
> > > > > Hi everyone,
> > > > > I've been looking for a 4-pole highpass filter like the A-123 which is not
> > > > > being produced anymore - very unfortunately.
> > > > > On top I found out that no manufacturer of eurorack modules seems to offer
> > > > > them. Very odd!!!
> > > > > I emailed Dieter Doepfer who shares my view on the sonic capability of a
> > > > > 24db high pass and also my surprise at the general lack of demand.
> > > > >
> > > > > Dieter Doepfer mentioned that he considers developing a new 4-pole highpass
> > > > > filter with a different chipset from that of the A-123 (CEM3320) - provided
> > > > > there is enough interest in this forum!
> > > > >
> > > > > So - please forum - I hope you are interested.
> > > > > And should anyone have a spare A-123 ... I'd be greatly interested ;-)
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > > [Non-text portions of this message have been removed]
> > > >
> > >
> >
>