Sunday, December 04, 2016

Synth DIY Part 2: The Noise Toaster

For my second project, I chose the Music from Outer Space Noise Toaster. This Ray Wilson design is a little synth in a box; kind of a condensed version of the classic MFOS Mini-Synth (about which I’ll write next). With one oscillator, an LFO, an ASR (Attack/Sustain/Release) section, white noise, and a legit filter with frequency and resonance control, the Noise Toaster looked like a more versatile and interactive device than the Weird Sound Generator. You can let it drone in many interesting ways, but even better, it encourages real-time tweaking. You could perhaps jam with it if you had some patient collaborators.

Here’s a recording of the Noise Toaster jamming with a drummer I know.

So, it was a more challenging project overall. I decided to make things more difficult by only ordering the circuit board and faceplate from MFOS. I felt confident I could source the other components myself because (a) I had two electronics supply stores in my neighbourhood, and (b) Ray’s book Make: Analog Synthesizers includes a whole chapter on building the Noise Toaster, with lots of pictures of the wiring and components. When faced with a wall full of potentiometers at the store, for example, I’d have a pretty firm idea of what I was looking for, and if I wasn’t sure, I could ask the folks at the stores.

Although ordering just the PCB and faceplate was cheaper than getting the whole kit, I definitely did not save any money on the project overall by buying the parts myself. If I’d had the confidence to order my parts online, I might have saved a bit—ordering the three 100k resistors I needed would have cost less than having to buy a bag of 10 at the store—but I learned a lot by going out in person and hunting things down.

The biggest pain, funnily enough, was finding the knobs. The pots I bought turned out to have stems that were too tall for the many cool-looking knobs at my favourite store. I bought a couple that had the old-school Moog style I was after (seen on the filters here), and they just perched on the pots like mushroom caps when I put them on—not flush with the faceplate as desired. Bummer. I did find the right ones once the store got some fresh stock in, well after I’d finished the rest of the project.

Also for this project, I bought a proper soldering station. My first iron had no temperature control. It seemed to get too hot, and the solder would boil. If I was going to be putting in heat-sensitive transistors and diodes, then I wanted to be able to back off the temperature a bit. So, this soldering station joined my mobile workshop. It’s rather dodgy, in that the first one I brought home did not work at all, but the replacement has behaved well since.

The box construction went much better this time. I used a simple design and learned that pre-drilling the pieces before inserting screws prevented the wood from splitting. Who knew? I also discovered a power saw in our shed, and that saved me a lot of time and trouble.

Here’s the result. Like the WSG, it worked straight away. It has an internal speaker, which in theory lets you play the Noise Toaster any time, anywhere. However, the speaker stopped working a couple weeks after finishing the project. I haven’t bothered troubleshooting it because I’m happy just plugging it into my recording interface whenever I want to use it.

No comments: