Wednesday, 15 November 2023

Jürgen Haible Wasp CV Filter

 Schematic is avaiable HERE.




24 comments:

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    1. Aw - now I'm blushing... I totally DO want to give this one a go. Unfortunately up to my ears with recording and also building for a small run of Marshall preamps based on the GV2 that is on here. I've got my eyes on this, and also the EAE Steiner filter which I'm hoping to get to work with an exp pedal for the freq control. Fingers X'd!

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  2. Quite fancy trying this with LM13700

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  3. Hmmm... What is VC on the bottom right of the circuit?

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  4. I think the 47K resistors going to pins 4 of IC 2 & 3 are 4K7?

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    1. Gave this one a try but can't get it going. I get clean from the first 2 rotary switch position, then nothing from the other 2. No distortion. Can't find any info online to check voltages, etc... Anyone else tried?

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  5. Hi Anders, you can tag this now with a few changes:

    The link from J22 - L22 needs to be I22 - L22
    The link from N17 - W17 needs to be N17 - pin 6 of IC3 (not sure when you could move the link to)

    After these changes it works as it should, although I haven't tested the VC input. Its a bit like the Systech Harmonic Energizer with a distortion option

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    1. Don't forget to tag this one Anders (couple of changes above). Happy New Year!!!

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  6. This filter is awesome. I built it a few years ago using another layout, and I like it a lot.
    Thank you for this layout!

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  7. @KG I built this, got it working, but have no idea what the VC is - any ideas? Many thanks in advance

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    1. Hi, Ian. Sorry, I can't remember exactly. Afaik, it's power-related (either ground or voltage)... I think the "V" stands for "Voltage".

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    2. I found a better schematic which shows CV (not VC). I guess its for an expression pedal but the schematic shows it as a mono jack, not stereo, so not sure how that would work.

      http://modular.fonik.de/pdf/Wasp%20Filter%20clone.pdf

      I may continue to play around with this one

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    3. CV stands for Control Voltage. You send an electric signal to modulate a parameter

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  8. Made a 10K expression pedal to test and it works. Pretty good filter pedal after all

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    1. Ian, I built this with your changes. N17-pin 6 of IC 3 was easy enough, just pushed jumper through cut at v17 and soldered to leg of pin 6 and the board. I wasn’t getting any sound when I switched distortion to connect distortion switch lugs 1 and 4, but I soldered these two lugs together and that worked. I also tried a 10k pot at VC and found 100k gave wider range. Any input or thoughts on your build are appreciated! -Rick

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    2. I also subbed a 2k pot for the 10k cutoff pot, since most of the effect was within the 1k range.

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    3. A wise change, there were a lot of dead spots with the 10K pot. Glad it works for you, its a good pedal. Similar to the Evil Filter with the added bonus of a working CV input

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    4. I came back to this one today and found a small omission in the layout (a cut is needed at s18). This is why the distortion wasn’t working (it’s pretty easy to spot in the schematic). With this change, as well as the one’s you note in your comments, everything works! I’m glad I came back to it. I think I’m going to box this with the PWM, which I just built and tested with the Wasp. Amazing noise possibilities!

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  9. Thanks guys! The layout is updated and tagged.

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  10. I’ve added an LFO to the circuit (connect output of LFO to CV of this layout). It works great. Here’s the schematic of the LFO that I used: https://experimentalistsanonymous.com/diy/Schematics/Oscillators%20LFOs%20and%20Signal%20Generators/Simple%20Dual%20LFO.gif

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