Tuesday, August 23, 2016
208r synth module (Buchla Model 208 clone)
via this auction
"If you're reading this listing, you're probably familiar with the provenance of these 208r modules. The PCBs and panel were manufactured in recent years in Russia to mimic the functionality of the Buchla Model 208, the sound-generating half of the legendary early-70s Music Easel portable synthesiser.
The Model 208 design is extraordinarily feature-packed - it's a fully-fledged monophonic synthesiser voice, whose principle circuits include:
A Complex Oscillator whose waveform can be transformed by its Timbre controls;
A Modulation Oscillator;
Dual Lopass Gates - vactrol-based circuits that can operate as low-pass filters, as VCAs (gate) or as a combination of both;
The Output Section, where the outputs of the LPGs are mixed. After the mixer, there's a spring reverb with a dry/wet control;
The Pulser - an impulse generator that can function as a clock source;
An Envelope Generator;
A Sequencer that is selectable between three, four or five steps and that features step gate switches;
A Random Voltage generator that outputs four separate and individual values at each clock step.
This particular 208r was assembled by an experienced builder and it's in perfect working order. As you can see from the photos, the panel is in excellent condition. The module is housed in a sturdy aluminium boat and is powered by an external PSU. My collection of Pomona patch cables and shorting bars is included in the deal!
The Music Easel allows for charmingly low-tech patch storage by means of special PCBs. Users can solder resistors to these cards and plug them into the Model 208's Program Board to impose preset values across the synthesis circuits. The 208r that I am selling is a rev. 1 and although its Program Board connector is fully functional, patch storage cards that can work with it have not yet been manufactured. However, a project is underway to make these available - search the Buchla board at the Muff Wiggler forum for details.
Lastly, if you're considering bidding but are unfamiliar with Buchla designs, I'd like to draw your attention to the following aspects of the format:
Buchla modules utilise banana-style patch cables, rather than the TRS standard that is used by most other manufacturers. However, Buchla modules can be integrated into Eurorack setups by means of format-jumbler boxes such as those manufactured by Low-Gain Electronics.
Buchla oscillators are scaled to a 1.2v-per-octave response (although they can be recalibrated to the 1v-per-octave standard common to other manufacturers).
The 208r is entirely analogue and does not feature a MIDI input. It is best incorporated into a MIDI setup by means of Expert Sleepers' excellent "Silent Way" software."