VOICE main core is a 8-bits Motorola 6809 CPU manages 8 voices polyphony.
A basic voice is composed by 1, 2 or 3 short samples with individual parameters:
- tune coarse / fine
- hard sync mode: OSC2 restarts its wave cycle when OSC1 finishes
- AM mode OSC 1 amplitude modulates > OSC2 amplitude (ring modulator concept).
WAVETABLE internal ROM is a 64 Kb (32 x 2 EPROM) wavetable coded at 8 bits resolution.
The wavetable contains 32t short cycled waveforms organized in 5 subgroups:
- mathematical pre-calculated waves
additives waves with variable harmonics contents
elementaries like pulse or saw
multisamples including the infamous "clunky" piano.
6 NOISE 1
7 NOISE 2
8 NOISE 3
11 EL PNO
12 VOICE 1
13 VOICE 2
|17 SYNTH 1
18 SYNTH 2
19 SYNTH 3
20 FORMT 1
21 FORMT 2
22 FORMT 3
23 FORMT 4
24 FORMT 5
25 PULSE 2
26 SQR 2
27 4 OCTS
29 BASS 2
30 E PNO 2
32 OCT +5
PERFORMANCE Esq-1 manages up to 8 parts with individual settings:
individual Midi chanel assigment
2 voices layer
- 2 voices
split in a user-defined point
special monophonic mode plays (1 voice stacked) with portamento and glide time
- panning can be modulated by EG, LFO, wheel, velocity, Midi CC# or pedal.
FILTER analog low pass at -24dB/octave resonant (not self-resonant) VCF based on 8 X Curtis CEM 3379 with key tracking level.
Like all parameters, the VCF is quantised and scaled in 30 t digital values.
ENVELOPE 4 assignable EGs each with a 4 stages ADSR + 3 time levels.
All EGs can be freely set to:
EG VCF filter
- EG VCA OSC2
- EG VCA OSC3
LFO 3 delayed modulators (shape: saw, square, noise and triangle) and many destinations:
- OSC1 pitch
- OSC2 pitch
- OSC3 pitch
- VCA amplitude
- VCF filter.
Modulation can be set to free flow or retriggered plus a special "human" function that gives a random feeling and non-linear frequency rate.
SEQUENCER up to 8 tracks with real-time record or step mode recording with quantizers, copy tracks, merge and loop function.
SYNC internal clock frequency or sync to external tempo using tape sync IN or trigger In (+5V at 24 PPQ) widely used by analog machines.
40 RAM patches
80 patcges on memory cartridge SQX-20
- 2400 RAM notes
- 10000 notes with memory expansion
TECH: ESQ 1 "Plus" version comes with double patch RAM and sequencer updated to 20000 notes.
Data can be saved on tape dump or directly to Midi Exclusive systems.
Battery repalcement: 3V soldered battery like this on the pictures, still easy to find on the market.
EDIT some computer-based softwares can make your life easier:
- Soundquest (mac/pc, commercial)
- ESQapade (Atari ST, now freeware) PIC
- Sounddiver (PC/MAC out of business)
- CTRLR (free) pic below
ESQ-1 RELATED FAMILY
The rackmount version imodel - it looks like an Ensoniq MIRAGE. It lacks the synth SEQUENCER and tap interface
VST PLUGIN / SAMPLED VERSION there are some free and commercial samples set: