PAiA 4700 Modular Synthesizer Rebuild

I rebuilt a PAiA 4700 modular synthesizer for a customer.  The customer built a custom cabinet and I and restored each of the modules.  I also built a custom power supply, power supply distribution boards, and several custom modules.


PAiA Modules

4710 Balanced Modulator

4711 Mixer

4712 Reverb

4720/4720A Voltage Controlled Oscillator

4730 Multi-Mode Filter

4740 Envelope Generator

4750 Control Oscillator-Noise Source

4780 Sequencer


Custom Modules and Panels

Power Module and Supply

MIDI-To-CV Keyboard module

Glide module

Bias module

Moog Ladder Filter module

Output module

Oscilloscope Module

Hz Interval Scaler Module  New



Additional PAiA Documents

PAiA 4700 User Guide

4761 Road Case Manual

4770 Watt Block Manual

4771 Regulated Power Supply Manual

4783 Joystick Controller Manual



Replacement PAiA Knobs

The original PAiA knobs are no longer manufactured.  They were push-on designed for splined or split-shaft potentiometers.  They are 0.680" diameter on the front and taper to 0.720" on the rear and are 0.620" tall.  I found the EHC  EH71-1C2S knobs are almost a perfect replacement.  They have dual set screws for a round shaft so they will fit on most any potentiometer shaft.  They are straight wall (not tapered) and the silver inset is not set quite as deep.  Newark and Allied Electronics carry them.

Knob Comparison

PAiA Original EHC EH71-1C2S
Front diameter 17.3mm 17.8mm
Rear diameter 18.3mm 17.8mm
Height 15.75mm 15.5mm
Shaft 1/4" splined 1/4" round
Mount Push-on Dual set screw