From Brian Benchoff on Hackaday:

3D Printing A Synthesizer

Before there were samplers, romplers, Skrillex, FM synths, and all the other sounds that don’t fit into the trailer for the new Blade Runner movie, electronic music was simple. Voltage controlled oscillators, voltage controlled filters, and CV keyboards ruled the roost. We’ve gone over a lot of voltage controlled synths, but [Tommy] took it to the next level. He designed a small, minimum viable synth based around the VCO in an old 4046 PLL chip

http://blog.tommy.sh/posts/hello-f0

http://blog.tommy.sh/posts/hello-f0

http://blog.tommy.sh/posts/hello-f0

The circuit for this synth is built in two halves. The biggest, and what probably took the most time designing, is the key bed. This is a one-octave keyboard that’s completely 3D printed. We’ve seen something like this before in one of the projects from the SupplyFrame Design Lab residents, though while that keyboard worked it was necessary for [Tim], the creator of that project, to find a company that could make custom key beds for him.

Read more on the F0 on Tommy’s blog:

Hello, F0

Say hello to the F0: a minimalist, analog, square wave synthesizer.