Razmasynth Unknown Pleasures

Unknown Pleasures is an Analog Tactile Noise Generator who use finger’s contact to produce sounds from Low Frequency oscillations to High Frequency Noise.

When the metal pads are pressed, the human body and the modular Synthetizer itself become a part of the circuitry to vary tonal response.

In addition, Sounds oscillations are converted to Tension and provide a CV Output from 0V to  3,70V.

Unknown Pleasures is based on an antique op-Amp from Soviet era. Sounds response  can vary depending the NOS MAA501 and user.

This is a little Eurorack kit, purchased and sent from France.  I bought two of these on a whim, while shopping for modules for my Eurorack controller skiff (of which more soon).

It is a clever design, consisting of a double sided PC board that uses surface mounted components.  I imagine that the assembled version uses actual surface mount parts.  For the kit, you just bend through-hole component leads and solder to the pads.  Helpful videos are available (see link above).

The chip is most interesting:  The MAA501 is a Russian made IC.  You can find a data sheet that shows the pinouts, but it’s in Russian!  Pins are brought directly out to touch pads.  Hope it doesn’t blow up.

Construction photos:

I used organic flux solder (Kester 331) for everything except the jack wiring, and washed the board prior to adding the jacks.  Notice that the power header is female. It comes with a double-male adapter and a standard Doepfer style power cable. I left off the adapter for the photos. Note the caption, “I feel it closing in.” I have no idea why this is named Unknown Pleasures or what the caption means.

Demo sounds

The first is the two audio outputs, one panned right, the other left.

The second demo uses one control voltage output, a low pass filtered version of the audio output, to modulate the cutoff frequency of a Serge VCFQ filter.