MOTM-800 ADSR Envelope Generator

MOTM-800 panelQuantity: 2 with my own DIY modifications and 2 with DB-800 modifications

From the Synthtech website:

The MOTM-800 provides the standard ADSR (Attack, Decay, Sustain, and Release) envelope for controlling VCAs, filters, and other CV inputs. Both positive-going (0V to +5V) and negative-going (0V to -5V) envelopes are simultaneously available.

Attack, Decay, and Release times can be set from 1ms to over 14 seconds using the smooth feel, conductive-plastic Bourns log pots.

The MOTM-800 actually can be operated in one of 3 modes:

GATE & TRIGGER: a full ADSR (Attack-Decay-Sustain-Release) cycle, with re-triggerable AD portion with GATE on and a new TRIGGER. GATE only: A-D-S-R using Roland “drop GATE” synths (SH-101, etc). MOTM-800s generate full ADSR cycles with GATE only. TRIGGER only: A-D cycle, useful for “stretching” drum pad envelopes.

DIY Modifications:
Added gate comparator with Schmitt function
Output limited to 5V max with clipping circuit
Output level LED

My modifications are similar to the DB-800 Daughterboard from Scott Juskiw.

Here is what my DIY perfboard modifications look like:

The DB-800 version before final assembly:

The DB-800 after final assembly.  I soldered all the wires, rather than use connectors.


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