James Husted of Synthwerks took the PNW AES Section through the history of Synthesis, with particular emphasis on Modular Synthesis. Today's modulars are related to early patchcord synthesizers such as the Moog 900-series, Buchla, and Arp instruments. It took instruments like the MiniMoog or the Arp Odessy to bring synthsesizer sounds to the performance stage, but these instruments, since their capabilities are predefined by the manufacturer, play a minor role in today's modular scene.

A patchcord synthesizer requires every element of the synthesizer chain to be connected to its successor processor. Synth modules may take control voltage (0-10v) or they may deliver control voltage. Of course, they may also input and/or output audio.

Typical modules might be:

• VCO - Voltage Controlled Oscillator: delivers sine, square, sawtooth, or pulse waveform in response to its control voltage
• VCF - Voltage Controlled Filter: could be any sort of filter, highpass, lowpass, bandpass, etc. The filter's parameters respond to one or more control voltages.
• ADR - Attack Decay Release: Processes a control voltage to impart an envelope on it having a defined Attack, Decay, and Release time. These parameters are usually knob controlled.
• ADSR - Attack Decay Sustain Release: Like the ADR, but adds a sustain parameter.
• Sequencer - Delivers a sequence of control voltages across a set time. Multiple control voltage outputs.
• Ring Modulator - Heterodynes its two input signals producing output signals (A+B) and (A-B), but ideally supressing A and B. See Wikipedia for a more exact definition and audible examples.
• Vocoder - Has two inputs. Input 1 feeds a bank of filters followed by VCAs, with the VCAs controlled by individual control voltages derived from a second set of filters, control voltage generators and envelope followers. The vocoder imprints the spectral informatin from input 2 onto the signal fed into input 1. The VCA outputs are then mixed and sent to the output.

We then took a break for nature's sake, and then enjoyed refreshments and social interraction. Door Prizes were awarded after the break.

In the second part of the meeting, James demonstrated using the components in his modular synth to create a particular sound.