Ensoniq ESQ-M (1987)
The ESQ-M is the rackmount version of Ensoniq's ESQ-1. Think of it as an ESQ-1 in a 1U rack, for keyboardists who wanted that sound without the keyboard. It's an 8-voice multitimbral synth module. Each voice has three digital oscillators running through an analog 24dB/octave low-pass filter, the same hybrid layout that made the ESQ-1 a hit. Each voice also gets three programmable envelopes (up to eight segments) and two LFOs, with a modulation matrix that was deep for its time.
There's no display, just a row of buttons and LEDs. You can program it from the front panel or, more practically, over MIDI. It has MIDI In, Out, and Thru, plus four individual audio outputs and a main stereo pair. Patch storage is 40 internal and 40 on cartridge, using the same cartridges as the ESQ-1. Unlike the keyboard version, there's no built-in sequencer. There's also an audio input for running external signals through the filter.
Recording Engineer (April 1987, p.94) described it as an 8-voice polyphonic, polytimbral synth module with three oscillators per voice and a choice of 32 multisampled and synthetic waveforms, noting the 40 on-board programs with an additional 80 cartridge programs available. The original price was $1,095.
Known specs:
- 8-voice multitimbral, 3 oscillators per voice
- 32 digital waveforms per oscillator
- Analog low-pass filter, 24dB/octave
- 3 envelopes per voice, 2 LFOs
- 40 internal + 40 cartridge patches
- 4 individual outputs + stereo pair
- 1U rackmount, approx. 8 lbs
- No built-in sequencer, no display
The ESQ-M is less common than the ESQ-1 on the used market. Owners note that the patch-select and edit buttons can become unreliable after decades. The internal battery for patch memory will eventually need replacement.
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