ms20 filter

[turing]

as suggested, i'm posting this as a seperate thread from my escobedine queries.
anybody built that ultimate filter  that is the korg ms20 hi and lo pass? it's always been my favourite, and i saw the schem on tim escobedo's site, but alas i don't know how to work from one.
if anyone has built one, and is feeling sporting enough to share some build tips/photos/layouts etc, i'd strew riches at their feet. (not literally)

[loscha]

I'd consult with Paul Perry of Frostwave. Several of his pedals are inspired from the MS-20's brilliant designs, including his Funk-a-Duck envelope controlled filter. I used one a while ago on that Electro-Harmonix Drum machine in a pedal, and it sounded totally amazing.

[Paul Perry (Frostwave)]

An ingenious version by Tom at EFM:
www.ele4music.com/pdfs/vcf8e.pdf
in particular note the HP/LP switch!!
My commercial Frostwave Resonator is just a slavish copy of the original MS20 (the second version of the filter) using NE5517s. (dual OTA)
Note I use +-15v rails!! as in the original. And the FEFM is +-12. Now it should be possible to adapt to +-4.5v, but I can't guarantee it will sound exactly the same..

[hank reynolds 3rd]

either the Tim ms20 type or a search in google (there's one with 2 opamps and a 13700/13600) ....
....remember you need a control voltage to make it sweep in an 'autofilter' style...
If you look at just the filter + attack/decay section of the modded oberheim filter at ggg's/jd sleeps site, you're pretty much there for guitar use, otherwise, I think you can just splice the attack/decay section from the oberheim or something similar ,to an 'original' ms20 layout...
i built an ms20 filter and haven't got around to the aforementioned mod's yet, so its just a theory that the above tips will work...

ta


Sam

[ExpAnonColin]

I want to know how Paul gets soft clipping.  A friend of mine built a +/-15V clone and his hard clips, just like my +/-4.5v version.

-Colin

[Paul Perry (Frostwave)]

I want to know how Paul gets soft clipping.  A friend of mine built a +/-15V clone and his hard clips, just like my +/-4.5v version.-Colin

I don't honestly know, but you could try changing the feedback diodes. I'm using red leds there myself.