First patch after tweaking the output level of my two benjolin’s. I actually built them quite a while ago but have had a lot of other projects on the go and have only just got around to sorting them.
Rob Hordijk’s original design was as a standalone units with a line level output. The fix was really simple, I just changed the gain of the op-amp feeding the filter. One little resistor and it only took me 6 months to get round to it!!!

Finally got round to finishing this filter and I’m very glad I have. It sounds fantastic.

I got the PCB quite a while ago when I swapped some of my boards with another user on Muffwigglers. Initially it didn’t work and it took me a little while to find the error on the PCB which was easily fixed with a jumper wire. I also decided to try it with my replacement for the LM3046 which is discontinued in a through hole package. My replacement uses 3 pairs of SMD matched transistors. I tested it with a real LM3046 and my replacement. There’s more gain in the LM3046 and the signal is a bit hotter but it still sounds pretty much the same with my replacement. As my stocks of LM3046’s are pretty low I decided to use the replacement. I’ve put a link to the project at the end of this post.

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In the video I have one VCO running into the audio input and one into the cutoff frequency CV input. Additional tones are produced by increasing the resonance.

Link to my LM3046 replacement:

Order from OSH Park

A bit late posting this as it’s February but here was January’s DIY project, a new case. Deviated slightly from the ‘technical drawing’ on an old envelope.

Here’s the build from plans to finished unit.

So, I was telling a friend that while working on something in my studio I’d been playing with putting my TR-707 drum machine through the Flights of Harmony Plague Bearer. As he was curious to how it sounded I made this little video.

The Plague Bearer is from the DIY run that Flight ran through the Muffwiggler site. I ordered and built 2 for enhanced sound mutilation and I’m still not sure I don’t need 4!!!