Catalyst Audio first introduced their Buchla 100 Eurorack modules back at NAMM 2017. Since then there wasn’t so much as a whisper and so I added them to my “Whatever happened to these synths” article. Shortly afterwards Dave from Catalyst Audio got in touch to say that they are certainly not “missing in action” and have in fact just started shipping the modules to preorders and dealers. They simply haven’t had any time to update the website or tell anybody about it. After some persistant poking Dave was able to give me the following details.
Buchla 100 Series Modules
Catalyst Audio aimed to accurately recreate the original, rare and much sought after, Buchla 100 series modules. They are entirely discrete transistor based analog circuitry with hand-matched components where applicable. The only adjustments have been made to conform to Eurorack specification. They have been extensively tested alongside the original 100 series system from the San Francisco Tape Music Center at Mills College, Oakland.
Model 158 Dual Sine-Sawtooth Generator
Dual analog oscillators with a 100% hand selected discrete transistor core. Sweepable between sine and sawtooth waves from ultrasonic down to LFO ranges. Linear FM available on each oscillator.
Model 180 Dual Attack Generator
To nicely compliment the dual oscillator these two envelopes offer attack, decay and note duration. When controlled externally this produces a classic ASR envelope, or internally it allows a sustain length independent of gate length. It can start with AD envelopes and go all the way to creating strange clocks and rhythms.
Model 106 6 Channel Mixer
Full of warm analog nonlinear distortion this brings some extra beef to the sound. It’s not designed to be a clean, hi-fidelity mixer. Separate mix outputs for channels 1-3, 4-6 and all plus an inverted “all” output.
Model 110 Quad Gate
Nonlinear analog VCA. The response is roughly exponential in the first 1/3 of its range, approximately linear over the middle 1/3, and increasingly logarithmic as it begins to saturate at the upper edge of its range. No vactrols are used in the 100 series gates allowing for an extremely fast response time and the ability to perform audio rate amplitude modulation.
Model 156 V Control Voltage Processor
Originally designed as a front-end for the 158 oscillator. It provides comprehensive CV control and manipulation including mixing, attenuation, offset and inversion. It was intended to be used with the Buchla touch plates and unquantized sequencers and so is less than ideal with the 1V/Oct Eurorack format. If you need to maintain the 1v/oct relationship then skip down to the 156 M below.
Model 156 M Control Voltage Processor
In order to better fit the 156 to Eurorack Catalyst Audio have come up with the 156 M. Designed from scratch and using modern components it addresses the 1v/oct issues of the 156 V.
Here are a couple of demos uploaded by beta tester “djangosfire”.
And a new video has just emerged from Perfect Circuit Audio:
The pricing is as follows:
- Model 158 Dual Oscillator – $449
- Model 110 Quad Gate – $299
- Model 180 Dual Attack Generator – $299
- Model 106 Mixer – $249
- Model 156V Dual CV Processor – $249
- Model 156M Dual CV Processor – $179
The website is still a disaster but hopefully, more information will come along soon. These modules could really bring some of that West coast avante-garde approach to synthesis right into your Eurorack for reasonable money in an accessible format.
- Catalyst Audio website.
- Catalyst Audio Model 158: Perfect Circuit Audio
- Catalyst Audio Model 180: Perfect Circuit Audio
- Catalyst Audio Model 106: Perfect Circuit Audio
- Catalyst Audio Model 110: Perfect Circuit Audio
- Catalyst Audio Model 156V: Perfect Circuit Audio
- Catalyst Audio Model 156M: Perfect Circuit Audio