Analog Synthesis 1972

I started my synthesis career in 1973 with module kits from John Simonton (PAIA). A module kit consisted of a circuit board, transistors resistors and capacitors. There was a circuit schematic and some instructions. You supplied the soldering iron and assembly skills. A basic system required 8 kits, one Voltage Controlled Oscillator, one Envelope Generator, one Voltage Controlled Amplifier, one Low Frequency Oscillator, one Noise Generator, one Low Pass filter and one Band Pass Filter. A power supply was required.

The VCO produced sine waves, square waves and sawtooth waves. The pitch was determined by a voltage input for a keyboard, for example. The simplest synthesis path was keyboard > VCO > EG >VCA> LPF to BPF > sound amplifier.

Synthesis 30 Years Later

Below is an EMU diagram showing the synthesis architecture in their P2500 and X2 Emulator. The Voltage Controlled Oscillator has been replaced with sound samples which loop to produce sustained sounds. Samples are digital files. Samples playback through a bank of filters and then an amplifier with envelope and panning controls. A host of variables control each stage of sound production. Amplitude envelopes creates the attack, sustain decay characteristics of an instrument. Low frequency oscillators modulate the amplifier to create effects such as tremolo and vibrato. Filters change the timbres of sound and sweep filters create moving timbres. Filters can be controlled by knobs on the proteus; by low frequency oscillators, by the keyboard and by foot pedals.

More About EMU X2 Sampler/Synthesizer

More About EMU Proteus 2500