Has anyone created a perf, strip or p'n'p layout for the Tim Escobedo 9V Sallen-Key/MS-20 filter? I've seen a few snippets of posts about it on this forum, but not layouts.
thanks in advance if you have one to share or can point me to a link!
- Strategy
I did a stripboard layout a while back. I've never tested it and it's pretty sloppy but it might work, in fact I can't remember if I finished it and the circuit snippets site seems down at the moment. I'll post it if you want.
Yeah please do, I'll experiment with it and, post updates or conclusions/outcomes as I can! This is really just to experiment with...
Thanks a ton!
- strategy
As I said it's rough, and I can't remember if I finished it, let me know if it works.
(http://img401.imageshack.us/img401/9132/ms20lpvcf.gif)
actually I think I did finish it, I never tried it though. I just looked at the schematic.
Thanks for posting, will check it out!
- Strategy
Did anyone try this out? I would be EXTREMELY interested in building this if it's verified. :icon_mrgreen:
It's on my list of things to do, along with a bunch of other stuff. I was gonna make one to use with an oscillator so I'll probably give it a go soon, I'll let you know how it goes.
Please do! Thanks!
Just built from the layout, all working fine, thanks! Plus it sounds much better than the other simple opamp vcf on escobedo's site. Now just got to look into clipping diode "like in other ms-20 clones".
Probably just being pernickety, but you could add a cable for Res-3 on the b line (the cv one) and make clearer the wire lines between b3 and d3 for capacitor c1.
Thanks again.
Ah, glad it works, I'd just built one myself but I haven't tested it yet, I'm not sure what you mean about your suggestions though.
Ah sorry, I meant that there was no offboard wiring detailed for Resonance lug 1 (i said res3 but meant res1!) and C1 is fine really.
Ah yeah, sorry. As I said, it was a while back I did it, it was just somet I fancied trying. I'll get mine going soon, I was gonna use it with a sequenced oscillator for a friend.
sorry for showing ignorance, but do these work with guitar? is there a way to make them work with guitar?
Any chance of some sound clips? I have a few pedals on my list already, but this is definitely something I'm going to do!
Quote from: Br4d13y on July 16, 2009, 08:49:45 PM
sorry for showing ignorance, but do these work with guitar? is there a way to make them work with guitar?
Well I haven't tried mine yet, but Mr Escobedo did adapt it for use with guitar so it should, I'll give it a bash soon and post back.
Quote from: mr.adambeck on July 16, 2009, 10:19:12 PM
Any chance of some sound clips? I have a few pedals on my list already, but this is definitely something I'm going to do!
I can try, I need to add some soundclips of other stuff I'm building, unfortunately I've no idea how to upload soundclips on the web.
What is this actually? You can connect it to an existing synth or what? (im guessing from the CV stuff)
Or where do you connect the "res", "freq" etc. stuff?
Quote from: WhenBoredomPeaks on July 17, 2009, 06:04:28 AM
What is this actually? You can connect it to an existing synth or what? (im guessing from the CV stuff)
Or where do you connect the "res", "freq" etc. stuff?
It's a variation of the Korg MS-20's sallen key low pass filter, it should make quite a good wah type filter. You should be able to use it ina synths audio path but bear in mind it runs off +9v.
I'll post a clearer layout soon, for now you can use the schematic on Tim Escobedo's site.
I haven't gotten to to build this yet...
It seems like this filter would be most expressive with either an expression pedal input or a CV input- exp pedal obviously better for guitar/bass, CV input for synth/modular applications.
Anyone consider this for the final wiring diagram? ...Possibly borrow the expression pedal input schem from another project?
- Strategy
suggestions for pot values on this one?
I think its 100k's. I've just built one based on the layout posted
http://img401.imageshack.us/img401/9132/ms20lpvcf.gif
and using this to wire it up (layout above has 2 extra resistors and uses 100nf input and output caps rather than 1uf on the one below)
http://i644.photobucket.com/albums/uu167/iloophao/2.png
I had some bit crushing effect with what sounded like the correct operation of freq and res controls, more signal passed when input level boosted alot, but still bit crushing sound until I found pin 1 of the ic had a solder bridge to the line above, after which nothing was happening at all.
Does anyone know or can confirm if the layout is good? I'm sure I've done everything correctly and on second look has no errors.
Andy
I've rebuilt this and have it working now, mixed up 2 of the caps on the last one i think...
As far as wiring goes res 1 is attached to h 19 (Vr?) and freq 1 goes to ground with freq 3 to the 9v line a
I also have the dc jack ground going to both grounds, not sure if that needs to be the case or not, but it works as it is.
I've changed the input and output caps to 220n and 470n, seems to have more bottom end, would that do it? Also changed the 2 100ks from pin 1 & 16 to 56k. Would that allow more bottom end as well as high end?
Andy
Hate to dig up an old thread, but I have a question about this effect.
I built it a few days ago, and works great (thanks to those in the thread who answered where all the pot wiring goes?).
My question is about CV in? I don't see CV in anywhere in the schematic, but I am new at these things so I may be overlooking it.
The Q&D filter scem and layouts had a CV in that worked great, would like to try to get the same with this MS20 filter.
I did try putting my CV source on a switch (to switch between the pot controlling Freq and the LFO), that works fine, but isn't what I wanted, I want CV to work like it did with the Q&D, where the Freq knob works with the LFO (changing the base freq of the LFO sweep).
Using the above Vero layout, any idea where I could pump in CV and still have the freq pot work?
(http://img294.imageshack.us/img294/5702/93446124.png)
- MikeT
I'd say use a summing amp to mix the voltage divider signal ( the frequency CV from lug two of the frequency pot) and your external CV from your LFO.
Quote from: daverdave on February 17, 2012, 06:58:06 PM
I'd say use a summing amp to mix the voltage divider signal ( the frequency CV from lug two of the frequency pot) and your external CV from your LFO.
That sounds like what I am looking for, but I am kind of a beginner at all of this, have a link to an example circuit of a summing amp I could look at?
- Thanks
toptop added cv in to tim e's idiot wah with a transistor and a couple of pots: http://oi56.tinypic.com/2r7qyh0.jpg (http://oi56.tinypic.com/2r7qyh0.jpg). you could try adding a transistor between the freq pot and ground in a similar manner.
(http://i.imgur.com/nV2LS.gif)
Quote from: PRR on February 18, 2012, 12:34:20 AM
(http://i.imgur.com/nV2LS.gif)
Thank you, that worked great!