PCB pattern for René Schmitz "late" MS20 VCF?

ericcoleridge · Joined: Jan 16, 2007 Posts: 889 Location: NYC

Anyone?

Edit: Hope you don't mind, I altered the text of the title of the thread to reflect that this is René's design, just in case anybody might think I had a hand in the design (I didn't), though I don't mind basking in René's glory Laughing

- Scott

janvanvolt · Joined: Nov 24, 2005 Posts: 285 Location: Mainz, Germany

midgetfidget · Joined: Aug 22, 2006 Posts: 84 Location: melbourne, aus

http://www.analog-synth.de/synths/mod2/ms20filter/rene_ms20_filter_clone%20rev%204.pdf

Scott Stites · Posted: Mon Dec 03, 2007 9:22 pm Post subject:

It's odd that this would come up - for the past couple of days I've been playing a lot with that module. It's a very powerful configuration. I'm not sure how close Rene's version comes to the actual "Late" version of the MS-20 filter, but this module produces some tremendous timbres.

My favorite mode of operation is to run a sawtooth through them in series HP->LP. I only modulate the LP section, I let either the HP or both track the CV. Now, the incredibly juicy part of it is to set the HP to full resonance, and slowly tune in various harmonics of the resonance. It produces some of the most incredible timbres - it more often than not sounds like you have two oscillators running at some very interesting intervals. Some of the sounds are exremely powerful, which makes me wonder how true it is to the MS-20 filter (I've invariably heard the MS-20 described as a rather "thin" sound, whatever that means).

One of the my boards in the module was an actual PCB I got from Rene when I visited him in 2004. The other was done on protoboard, and the extra control circuitry was put on protoboard as well.

Cheers,
Scott

frijitz · Posted: Mon Dec 03, 2007 10:05 pm Post subject:

Scott Stites · Posted: Mon Dec 03, 2007 11:15 pm Post subject:

Hey Ian,

That rings true to some degree; it's rather an odd duck compared to my other filters.

With no signal input, it oscillates like a bat out of hell once the resonance control hits a certain point (I often use it, through the wave multiplier, as a spare oscillator). If you crank the resonance knob up higher (with no input) you still have solid oscillation.

With a signal applied, there's a certain balance to the input level and resonance. I'm sorry, I don't have any measurement data for you, just anecodotal info at best, but when the input is attenuated, it's easier to get oscillation - with a lot of input, the filter is less likely to oscillate, and the resonance becomes less pronounced.

Output level wise, it's never a problem - if you want a lot of resonance, and you lower your input level, the resonance picks up the slack, so to speak, in the output level. When the cutoff is swept, with high resonance, it's a very "dirty" kind of resonance - it's not (oh, God I hate these descriptions) a "creamy" resonance by any measure. When the resonance is high, but is not swept, but rather is tracking the same voltage that's controlling the VCO that is feeding it, that's where the real magic begins to happen for me.

Don't get me wrong, if I want very extreme "weird" it'll supply it, but I really like the effect of mid level input signal, and very high resonance tracking the V/Oct input, usually in the HP mode - it's unbelievable the timbres it can produce. Much like the physical modeling thing we discussed briefly a while back. Though the filter itself tracks V/Oct mildly well, it's not all that great, obviously. However, the resonance effect tracks the input well over a very wide range, much wider than the V/Oct response of the filter itself. That's another thing that makes the effect so nice.

Does your math have any explanation for the following, perchance? - The effect I'm talking about here works primarily with a sawtooth input - it's very easily controlled. A pulse input tends to make the resonance wiggle around a lot, doesn't "track" as far, and is therefore generally not as convincing. Is there any reason you can spot why this would be so?

I ought to see if Rene is interested in this thread. Haven't heard from him forever....guess that's because I haven't emailed him since forever. Embarassed

Cheers,
Scott

midgetfidget · Joined: Aug 22, 2006 Posts: 84 Location: melbourne, aus

i had a frostwave resonator (which is a clone of the ms20 filter) and that thing squealed with resonance if you turn the knob much past 12 o'clock.

v-un-v · Posted: Tue Dec 04, 2007 2:41 am Post subject:

Well I've got the real thing - an MS20 that is, and the self oscillation on both high and low pass filters is vicious! (And I MEAN VICIOUS!!). The self-oscillation also covers a very wide frequency sweep range- it kicks in pretty quickly indicating that the filter is rather unstable. The sub is low enough to take speaker cones out. Shocked

As for the sound, the MS20 oscillators are very 'weak'-sounding ie they don't sound very 'American'. They are definately Japanese sounding- sometimes rather Casio-like Shocked

The filter has a lovely raw, gutsy sound- quite 'wooden' in body (similar to the Mono-poly filter, but not as naff sounding- I never liked the filter on the mono-poly). However, filter feedback makes the MS20 really squeal, adding something 'extra-special' and I think that's what people like about them (Listen to Caustic Window/ AFX/ Aphex Twin sometime- when Richie was doing his hardcore 'porn techno' stuff Laughing

)

The best thing about the MS20 is the external signal processor, and this gets even better when used with the MS20 dual filter and the oscillator in 'ring mod' mode. Plug a TB303 into this, and it goes mental!! Sounds good when processing drum machines too!)

It's a strange synth. It's too limited in the patching dept to be called a modular as such. It's one of those machines that really needs 'hacking'.

v-un-v · Posted: Tue Dec 04, 2007 2:48 am Post subject:

Clack · Posted: Tue Dec 04, 2007 3:01 am Post subject:

loss1234 · Posted: Tue Dec 04, 2007 6:00 am Post subject:

anybody know what kind of transistors those are supposed to be? bc's or 2n's?

midgetfidget · Joined: Aug 22, 2006 Posts: 84 Location: melbourne, aus

i've wanted an ms20 ever since seeing jamie lidell sing and process his voice through one, he was making some insane noise.

I agree about the DAF lyrics Smile

softfin · Posted: Tue Dec 04, 2007 6:30 am Post subject:

frijitz · Posted: Tue Dec 04, 2007 6:32 am Post subject:

Wow, thanks for all the replies. I found my math error -- the filters oscillate for feedback gain over 2.

Very Happy

Ian

v-un-v · Posted: Tue Dec 04, 2007 7:33 am Post subject:

Scott Stites · Posted: Tue Dec 04, 2007 8:03 am Post subject:

I matched the transistors, and it does a pretty fair job of tracking (there's no temp compensation). In fact, a good number of my Klee samples use one section of the filter as a VCO. Generally, I'll run the oscillating output out of one section, pass it through the wave multiplier, then patch it back into second section to filter that signal.

"Berserklee2" uses it as grinding low voice here

http://www.electro-music.com/forum/download.php?id=9915

Through Dim C, it produces the high airy notes in the 32 Step Klee sample here:

http://www.electro-music.com/forum/download.php?id=9912

And the high notes for "Ice Kleem Truck" here:

http://www.electro-music.com/forum/download.php?id=9938

Cheerios,
Scott

ericcoleridge · Joined: Jan 16, 2007 Posts: 889 Location: NYC

ericcoleridge · Joined: Jan 16, 2007 Posts: 889 Location: NYC

frijitz · Posted: Tue Dec 04, 2007 1:40 pm Post subject:

ENDIF · Joined: Jul 14, 2006 Posts: 138 Location: Reno, NV

@ Ian

An extra meaty MS20 filter clone?
Yes please!
=D

Alienation · Joined: Jul 23, 2007 Posts: 47 Location: Midsouth

Looks like a good project for a couple of CA3080's laying around here somewhere. Very Happy

Are there any PCB patterns around for the Rene Schmitz VCO3 ??

6079smith · Posted: Tue Dec 04, 2007 3:15 pm Post subject:

fonik · Posted: Tue Dec 04, 2007 3:59 pm Post subject:

[quote="Mr Clack"]

Luka · Joined: Jun 29, 2007 Posts: 1003 Location: Melb.

i dont really understand why people say ms20 is thin and cold, ive made some of the most thick and warm bass tones on the legacy vst, it took a while but nothing has come close since. i have wanted an real ms20 for so long

v-un-v · Posted: Tue Dec 04, 2007 4:56 pm Post subject:

It's capable of both. I've used the external signal processor to feed the signal back into the filter's external inputs. This creates some really 'fat' bass/ leads.

I suppose this is also why it now sells at stupid prices? I've had 4 MS20's all in all. This one is my original one that I found in the Bristol trading pages for £35, about 14 years back. There are two on ebay now for over £800 each Shocked

If the MS20 can be cloned (or at least part of it), it should be done ASAP!

Apparently the MS10's filter sounds 'fuller' Confused