The Sound Lab Is a Simple Analog Synth

The Sound Lab, by Technoblogy's David Johnson-Davies, is an analog (analog) synthesizer. The device implements six sound modules – LFO, envelope generator, oscillator, filter, noise generator, and amplifier – that combine to produce sound output. Johnson-Davies reports that it's capable of creating a wide range of audio output, including weather sounds, animal noises, mechanical sounds such as sirens and engines, and even speech-like sounds.

As versatile as it is, the Sound Lab is constructed without any sort of microcontroller whatsoever. It instead relies on components such as resistors, capacitors, and diodes, along with integrated circuits like LM555D oscillators and LM358 op amps. Each sound module forms its own circuit, as described in the Johnson-Davies' Technoblogy write-up, and an overall schematic is available here if you’d like to view the synth in its entirety.

While the project could be intimidating if you’re thinking of taking it on yourself, note that everything is built into a single PCB, which takes care of the vast majority of wiring. Controls, including 12 potentiometers and 10 SPDT toggle switches, are through-hole mounted to the front, while surface-mount electronics are soldered to the back, spec’d in approachable 0805 and SOIC packages. And there’s no programming to worry about!

It’s a rather impressive display of analog design, and Johnson-Davies notes that this synth was made in collaboration with Chris Jordan. It looks like a lot of fun to use, generating a wide range of sounds. However, if you want to reproduce what you made at a later date there’s no saving things. You therefore may want to take a picture to help dial the settings back to a previous state!