Ms-20 filter is alive!!
1999-03-30 by Paul Schreiber
Great news! The MS-20 filter "section" is working on the hand-wired breadboard. All 3 modes (HP/LP/Notch) work great. Reso can be adjusted to kill squirrels at 50 paces. I need to snarf my buddy's MS-20 this weekend and give it the A/B ear thing. By then I will have 2 VCOs built up so finally a real "synth" emerges from the quagmire. Kit difficulty will be about like a '120. 2 trims, but these are all by ear (cutoff @ 0CV and reso madness). I suppose for people building poly syths, you need to trim the cutoff with a scope (to match sections the same). We now have an official price: MOTM-420 is $159 kit, $219 assembled. The price is slightly high due to the number of jacks/pots and the 1V/octave tracking (tempco resistor + PNP matched pair). Save some heat goop! The panel (attn: Dave!) is looking like: CUTOFF RESO MOD 1 AUDIO 1 MOD 2 AUDIO 2 MODE AUDIO 3 1V/O CV1 CV2 IN1 IN2 IN3 OUT Hopefully Dave B. will find 3 audio ins and 3 CV ins sufficient <grin>. Has anyone picked up that this means no audio mixer module is needed immediately ? <hee hee>. And as a bonus MOD 1 can be set for - to + sweeps over s 3 octave/v range. Yeee Haaaaa!! Lastly, may add a "we are clipping you moron" LED but I am seeing too much part-to-part variation for my liking. Now I can breath a little easier and get those VCOs out the door! Spent 5 hours de-glitching the sine wave, and I think I got it at a minimum. Feel free to send in your '420 orders early!! Subscribers will get 1 automatically, as usual. Estimated ship date is 1st week of May or perhaps sooner if the VCO mailing goes smooth. Paul Schreiber PS: the website in the month of March has transferred over 2GB of data! A new record! Thanks, Keyboard!