Wednesday, December 4, 2024

THREE NEW MODULES!!!!


Three? Really? Yes!!!!

Okay first off, my modules are being sold now by my very good friend Mike (Killer Bee Relay Team) over at Hive Mind Synthesis. His whole outfit is so much better qualified to handle the sales and customer service side of this than me, and I'm SO THANKFUL and happy with how it's turning out.

Next? The three modules! These aren't retail-ready, but they've been kicking around in my brain for a long time, so I'm happy to have prototypes being made right now by JLCPCB (not a sponsor). Read about the three modules after the break. 

1) VCSlope
This is half of a DUSG, the D standing for dual, and my module is just a single. Universal Slope Generator is what the rest of the acronym stands for, and the DUSG is a backbone of one branch of the west-coast synthesis style. Serge Tcherepnin developed the DUSG as part of his efforts to bring synthesis "to the people" (quoting the Wikipedia article YAY!) with small, cheap, DIY synths. Wow. Marxist icon Serge Tcherepnin.

Anyway, I very quickly slapped a circuit together about a year ago, had 10 printed up to see, and pow, they work extremely well and I love the. So I refined the circuit and the electronics a *lot* and they're the first module I've got printing right now.

2) TriplePlusBass
I love the DoublePlusBass, but I never was happy with the envelope controls. I spent hours of my life trying to figure out how to derive the um, IDK the math term for a slope that's the inverse of another slope... inverse? Anyway, the 909 pitch envelope (which the DPB copies) drops quickly and then slowly tails off, depending on the value of a resistor in a resistor/capacitor filter. I want an envelope that stays high and drops off right at the end. But analog electronics don't know how long the envelope is expected to be, so they can't decide when to drop off right at the end, right??? Makes sense??? So the TriplePlusBass is a module which uses a microcontroller for the pitch and amplitude envelopes. This means I can get a stabby 909-style pitch drop, a saggy 808-style pitch drop, a perfect linear pitch drop if I want that, and MORE!!!! because I'm also controlling the amplitude envelope with the microcontroller! So at maximum "decay" the kick drum's signal is just playing the whole time, turning the module into a VCO. I ended up using 11 potentiometers (this time they're all clear-shafted Juanitopots) but ditched the ducking signal output, adding a FOLD option, which is applied post-amplitude. If it works, it'll distort the kick sound in very pleasing ways.

Okay so this module? I haven't written any code for it yet, because it's gonna use the AVR128DA processor, which I'm not super comfortable coding for. It'll need to be able to put one CV out of the pin attached to the internal DAC, and output one CV from a resistor ladder DAC I hung off eight of the pins. Also, it's gonna have to control four APA102 addressable LEDs to show what some of the knobs are doing. Yikes. Think I'll be able to code it??

3) My tin can synth has an Engineer's Thumb compressor in the kick drum signal path, and some of those settings do MONSTROUS things to the kick. And the Engineer's Thumb compressor is a 9V single-supply design, which I copied faithfully back before I could easily convert circuits to use typical bipolar synth power supplies. So my third module, designed and printed on a whim, is the HungryThumb, an adaptation of the clever compressor design by the Valve Wizard person. I put a starve function in the HungryThumb, copied from my HungryRat module. I trimmed the controls down to Attack, Release, and Ratio, compared to the 5 knobs my tin can Engineer's Thumb has, but adds a VCA on the output because there was a whole side of an LM13700 just hanging out on the PCB, what am I supposed to do?

Also, analog synth design nerds take note: this circuit is the first one where I'm using the linearizing diodes on the LM13700. What they do, gentle reader, is allow you to use MUCH higher input voltages without the OTA distortion all OTA circuits introduce with voltages over like 30mV?? Anyway, the linearizing diodes distort the signal in the other direction, leaving us with an undistorted output with a much MUCH better signal-to-noise ratio. Never used those diodes before, I wonder if I'll be able to hear a difference doubt it.


Okay, I was tempted to add a Baxandall tone control to the HungryThumb, but I didn't It's a nice compact 6HP module the way it is, and I'm excited to play with it when it arrives.

 I guess that's about all! 

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THREE NEW MODULES!!!!

Three? Really? Yes!!!! Okay first off, my modules are being sold now by my very good friend Mike (Killer Bee Relay Team) over at Hive Mind S...