Old Tech Synth Site

KEYBOARD

BEND: —Approximately one tone up or down with 90° centre "dead band".

TUNE: — Approximately one tone up or down (pre-set to A=440 Hz).

GLIDE: — adjustable up to 3 second sweep over two octaves.

OSCILLATORS

Oscillator 1: choice of five octaves—32' to 2' sawtooth or pulse adjustable from 10% to 50% duty cycle.

Oscillator 2: As oscillator 1 but with sawtooth or square waveform; pitch continuously variable over more than one octave, encompassing oscillator1 pitch.

CONTROL OSCILLATOR

1 Hz to 100 Hz approx.

Sine, rising or falling sawtooth, or, square waveform. Also available for control are white noise or noise sampled and held at control oscillator rate. Pitch of oscillators 1 and 2 can be modulated by approx. +/- 1 tone from control oscillator;

NOISE

Level control adjusts amount of white noise added to oscillator signals (Oscillators 1 and 2).

FILTER

Low pass, band pass (fixed bandwidth) or high pass. 'Q' factor adjustable from maximally flat to verge of oscillation. Automatic overload limiter. 12dB/octave roll off in low or high pass. 6dB/octave in band pass.

Turnover frequency is proportionally control led by control oscillator*, control envelope generator. and manual frequency control. Turnover frequency is also proportionally controlled by keyboard. Frequency range 3-16 KHz
*continuously variable control from +Ve to —Ve

ENVELOPE GENERATORS.

1. VCA ENV. GEN.: — linear attack rate variable from 3mSec. to 2 Sec. Exponential decay rate variable from 3mSec. to 12 Sec. Decay is interrupted by a sustain period while the keyboard is being touched. The sustain signal level is adjustable. The repeat function causes continuous attack/decay cycles while the keyboard is being touched.

2. Control ENV. GEN.: Triggered by VCA ENV. GEN. via delay adjustable up to 1 Sec. Linear attack and decay rates separately adjustable from 15mSec. to 6 Sec. Repeat function causes continuous attack/decay cycles to occur.

OUTPUTS

Power on/volume control adjusts line output, headphones output and loudspeaker level.
Nominal output characteristics at full volume: —
Line output: - 10dBM, 600 ohms
Headphone output: — OdBM, 50 ohms
Noise level at line output in quiet state:— 65dBM

POWER CONSUMPTION

45mA with speaker not is use
150mA at max. speaker volume.

INTERFACE

Three state interface lines — one trigger and 6 code lines.

COPYRIGHT JUNE 5th 1978
PATENT APPLIED FOR 39335/78

Electronic Dream Plant Ltd.
Red Gables
Stonefield Road
Combe
Oxford OX7 2ER