Creating sound with musical instruments is as old as human history, but wide ranging as those sounds may be, we're limited by what those instruments can do. Electronic circuits, on the other hand, can generate sound waves in almost unlimited variations and combinations, many impossible to recreate any other way. If you've ever heard music and you couldn't quite figure out what sort of instrument they were using, there's a good chance it was a synthesizer. If you've heard what's known as "space music," you've heard lots of synthesizers.
A few years ago a really interesting book was published in the Make series, Make: Analog Synthesizers by Ray Wilson. If you're a hands on builder, know a little electronics and you like your projects to do something besides just sit there, this might be right up your alley. If you like space music and those soundscapes that trigger visions of Sci-Fi movies with space ships traveling to distant planets (Remember Forbidden Planet?), stop and buy this book right now.
Ray walks you through an introduction to synthesizers, the differences between digital and analog synthesizers, discusses what you'll need when setting up your workbench and then takes you through many of the basic building blocks of synthesizer circuitry like filters, oscillators, envelope generators and the like. There are lots of building tips for the novice and a thorough discussion of the "noise toaster," pictured on the cover of the book and at the top of this page. It's amazing what kinds of sounds you can get from what appears to be a simple box with a few switches and knobs on the front. Really, truly amazing. All of the sounds in the video below are from this box! Multiple tracks were recorded and there you have it. Ignore the silly graphics, (vintage flying toasters) concentrate on the sound.
Since Ray's passing, some of the components like faceplates and circuit boards are no longer available on the website. The drawings and schematics are all there, in fact all of the information you need is readily available in this book and on his website, though there will be more "hands on" necessary than previously. Whether some of those parts or kits will be available again is unclear, but again, they are not necessary, you just need the knowledge and desire to build one.
You can even breadboard the circuits and make this without any case or circuit board if you just want to test it out. Then, if you want to learn how to make the nice looking printed faceplates you can do that. Printed circuit board construction is getting easier all the time, too and when you're through with those, a wood box, should be the easiest part. There are even easier projects than this one and more advanced ones if you're a little more skilled to begin.
Synthesizers are having a bit of a renaissance right now, so if your building skills are looking for a new challenge with a satisfying payoff, go make some noise.