Shruthi synth module with digital filter/FX designed by Mutable Instruments

via this auction

"Newly built Shruthi synth as originally designed by Mutable Instruments. Only used for testing.

The design is usually a hybrid consisting of a digital oscillator board and an analogue filter/VCA board (there is a selection of filters to choose from). This however is the fully digital filter board which, although lacking in analogue goodness, brings a crunchy lo-fi range of possibilities. Being digital, the filter also has a built-in range of effects including: delay, comb filter, distortion, bit-crushing, pitch-shifting, micro-looping, ring modulation etc. It is also possible to process external audio via the filter and effects.

There is no enclosure supplied but cases can be found on ebay.... or laser-cut yourself one from the open-source files. Knobs are included but the square push button caps are not. These can be sourced from Mouser or Digikey with the following part numbers:

Digikey: EG1081-ND
Mouser: 611-F1201

The unit runs on a 7.5v - 9v DC power supply which is not included!

Display is a nice blue on black and the LED's are also blue.

The manual is available here.

Details of the filter and effects can be found here."