ADDAC System ADDAC104 VC T-Networks - Noir

Four twin-T percussion voices in 8HP, based on the same circuit topology that gave the TR-808 and its contemporaries their toms, congas and rimshots. Send a trigger and each channel rings out a short, decaying pitched click — dry and woody at the low end, sharp and metallic up top. What the 104 adds over a vintage drum machine is voltage control: every voice has a frequency knob, a Low/Mod/High range switch, and a CV input with attenuverter, so pitch can be swept, sequenced or modulated per hit.

The trigger inputs run through gate-to-trigger converters and happily accept audio-rate signals, which turns each channel into a strange, destructive resonant filter — one of the more interesting corners of this module and a good source of gritty, unstable texture well outside drum duty. Note that the CV inputs are not calibrated to 1V/Oct; this is by design. The top two channels sit in a higher frequency range, the bottom two lower. Four individual outputs plus a summed mix out with its own volume control.

Condition: excellent. Panel graphics fully intact, no rack rash, all knobs, switches and jacks tight. Serial no. 106, built August 2019. Tested and working. Ships with ribbon cable and mounting screws.

Specs: 8HP, 25mm deep, 50mA +12V / 50mA −12V.

Shipping from the Netherlands, tracked. Offers welcome.