Dual Oscillator Model 258

Two independent voltage-controlled oscillators, continuously tunable from 5 Hz to 20 kHz. Each has two processing inputs and a frequency modulation input. Waveshapes as well as frequency can be voltage controlled. Model 258 oscillators feature low sine wave harmonic content, negligible settling error, and high short and long-term stability, even with rapidly changing ambient temperatures.

Controls and I/O

Processing inputs

Two processing control inputs permit multiple control of pitch without need of separate external processor.

Processing controls

Used to set desired range of frequency control. Expansion, compression, and inversion of scales are accomplished here.

Frequency modulation control

For adjusting vibrato depth or creating clangorous or bell-like tones, rich in non-harmonic partials.

Output

Signal amplitude is +4 dB. Output impedance is 600 ohms.

Oscillator frequency control

Spans the audio spectrum of 5 Hz to 20 kHz with no range switching. (Applied control voltages can extend limits to .1 Hz and 30 kHz.)

Waveshape control input

Waveshapes can be varied from sine to saw (osc 1) and sine to square (osc 2). Voltage control of waveshape enables powerful dynamic control of timbre.