WASP VCF clone

fonik

...still on breadboard. VCF core works fine... the other parts will have to be checked next weeks...
http://www.modular.fonik.de/Page38.html

Funky40 · Posted: Sat Sep 15, 2007 11:36 am Post subject:

Peake · Posted: Sat Sep 15, 2007 1:14 pm Post subject:

I've never heard the Wasp filter. Does anyone have a link to audio please?

I really like the added distortion. Everyone is going to throw their individual ideas at you, so pick and choose (and choose the above idea of switching one channel of CV in and out- great idea!). Would it be possible to have another distortion mode, to be able to switch it in prior to the filter, to distort just the input, as well as the given option of distorting the output?

No problem if not, just throwing ideas on the wall to see if any are worthy of sticking. Good work!

fonik · Posted: Wed Dec 12, 2007 4:03 am Post subject:

got the proto working - not satisfied by the CV response, though.
below is a simple sound sample. you'll find additional samples especially of the resonance behaviour in the MS20 thread.
http://electro-music.com/forum/topic-22235-50.html&sid=313d4fc60fa10de9235f8c62622a732a

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wasp_01.mp3

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a first sound sample, nothing fancy...

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wasp_01.mp3

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etaoin · Joined: Jun 30, 2005 Posts: 761 Location: Utrecht, NL

Fonik, does it work out alright with the 4069? I remember reading somewhere that Seb Francis said that when running in linear mode, you should not use more than three gates from the same chip or they would run too hot. That's the reason he split the two distortions in his Box-O-Trix over two 4069's and left three gates unused in each IC.

v-un-v · Posted: Wed Dec 12, 2007 4:29 am Post subject:

fonik · Posted: Wed Dec 12, 2007 4:45 am Post subject:

6079smith · Posted: Wed Dec 12, 2007 7:14 am Post subject:

Hi fonik, I built a Wasp VCF from your original design and I was well pleased with it. The only drawback was a slightly lower output than, well, other modules I have. I never thought that the 4069 got particularly hot, but I don't think I tried touching it... (that reminds me to start another thread). I noticed that also about the CV control not being wonderful. But it works, and sounds pretty unique. Nice work, and thanks for it.

fonik · Posted: Wed Dec 12, 2007 8:38 am Post subject:

6079smith · Posted: Wed Dec 12, 2007 1:01 pm Post subject:

crashlander42 · Joined: Oct 21, 2006 Posts: 292 Location: Orlando, FL (US)

Sounds great and looks great!
The Wasp filter that I built from the layout on your site is one of my favorite filters in my setup right now.

Are you going to be doing a run of boards, or releasing a press n peel layout?

I am eagerly anticipating either. Laughing

The Alison Project · Posted: Wed Dec 12, 2007 10:37 pm Post subject:

I have the previous version you posted in my synth, looks like I need some upgrading.

good job and thanks

Peake · Posted: Wed Dec 12, 2007 11:16 pm Post subject:

bugbrand · Posted: Thu Jan 31, 2008 3:50 pm Post subject:

Hey, I've been thinking on Wasps too recently... So have been interested to read through this thread and dredge it back up again.
I've got a couple of questions / ideas..

- Firstly - the original ran with a 5v single supply for the filter and Jurgen's schem had been marked like that. Matthias, did you try with 5v and 12v? I was wondering whether this'd make much difference other than headroom / where overdrive sets in.. I really want to test these circuits out and see how they respond to different input levels.

- also, I see you've got a switch to select different diodes - did you notice much difference? Hmm, different coloured LEDs have different sounds too, right? (or is it so subtle you really won't notice?)

* my main fresh idea has been to have a post filter mixer stage. I've seen something a bit similar by Craig Anderton before (in the EPFM book) - you get a three channel mixer for HP, BP, LP -- nice sound shaping, no?! This could also help bring the level back up again after the filter (especially if running at 5v). Now, I also wondered about the phase of each output - are all three in phase (I *think* they are?!)? I'd thought to use the left-over three 4069 gates as inverters for each output instead of employing them for overdrive - you'd then get a phase switch for each mix input and I'd think you'd be able to get some great tone shaping possibilities out.. Hmm, gotta try this out!

[Adding an inverter stage would, I think, just be a case of tapping the original response output with a 100k resistor, followed by a DC blocking cap (seeing that from Jurgen's Wasp schem) and then the inverter gate with another 100k resistor strung across as feedback.. ]

Any thoughts or comments?
Matthias - you said the CV response wasn't working so good on your prototype? I'm sure a number of typical lm13700 driving circuits could fit the bill perhaps?

***
Oh yeah, apparently the dirty noise band Whitehouse are characterised by the sound of the Wasp....

numbernone · Joined: Aug 16, 2006 Posts: 477 Location: new york city

Early Whitehouse is entirely Wasp driven. Great stuff.

fonik · Posted: Sun Feb 03, 2008 4:17 am Post subject:

etaoin · Joined: Jun 30, 2005 Posts: 761 Location: Utrecht, NL

fonik · Posted: Sun Feb 03, 2008 4:48 am Post subject:

bugbrand · Posted: Sun Feb 03, 2008 6:55 am Post subject:

One more thing I was wondering on was the driving of the Ca3080 (or LM13700 as I'm going to try) -- hmm, I don't really understand the internal workings so maybe I'm already falling down..

But, if we're powering the OTA with a single supply (0-5v or 0-12v or 0-15v) then can we still drive it with a standard exponential converter run off a bipolar supply? Or would be have to add in some sort of offset control? Uhh, I'm showing my lack of actual understanding here probably!

Oh well, this is on my more imminent ToDo list! I've sketched out plans for the main filter part with inverters for the outputs.....

I don't know what you'd think, Matthias, but I may be up for doing some PCBs at some point too... Dunno, I've also got a lot to juggle at the moment (don't we all!)

Fernando · Posted: Tue Mar 11, 2008 1:05 pm Post subject:

Hi all. Been offline for a while.

I like the Wasp very much. I never built the JH version but I played a real Wasp around '80. I like it.

I just wanted to add that the 3080 might be a better option since it can reach to a nice soft distortion when pushed a bit. I know that 13700 is easier to buy but I'd use the 3080 better... just my opinion

cheers,

fernando

widdly · Posted: Tue Mar 11, 2008 3:26 pm Post subject:

Hey fonik,

I noticed in another thread you posted some samples of your wasp filter self oscilllating. I built a version straight of JH's schematic into an old expression pedal but mine never self-oscillated. What's the trick?

http://electro-music.com/forum/topic-22235.html&postorder=asc&start=50

jhaible · Posted: Tue Mar 11, 2008 3:30 pm Post subject:

widdly · Posted: Tue Mar 11, 2008 3:45 pm Post subject:

I need an output buffer?

jhaible · Posted: Tue Mar 11, 2008 11:55 pm Post subject:

widdly · Posted: Wed Mar 12, 2008 1:24 am Post subject:

I have re-read your Wasp Clone page and I understand what you meant by "capacitance of a long cable at the output". I will have to try this out. From building guitar effects, I'm used to long cables causing problems not fixing. Smile