Somewhere around the age of 5, my daughter became interested in my Roland SH-101. Unfortunately, I use it most of the time that I'm writing
music, which left her very little time to play with it. That year I decided to build her a noise synth for Christmas, so she'd always have something
to play with when I'm writing.
The idea was to create a simple single VCO synth with multiple modulation sources... the result was a fun little project perfect for making
"Forbidden Planet" style sci-fi sound effects, bleeps, squeals and other noises that are intriquing for a 5 year old (well... most of my musician
friends like it, too... so that's either a comment on their maturity level, or an under-estimation of the value of this little black box... I'll let
you decide)
My biggest regret about the entire project was my time schedule. I decided to build this around the 20th of December. It took me a day to
decide what components to use, and create the faceplate design. I then did three days of frantic late-night building to get it complete by
Christmas Eve. For this reason it's a bit messy inside, and I'll spare you the horrors of a peek under the hood.
The Toybox has the following components:
- ASM-style VCO (tri / pulse)
- Moog VCF (EFM VCF-2)
- Two tri/square LFOs with hi/lo rate switch (routable to Pitch, Pulse width, Cutoff, Resonance, VCA level)
- A/D envelope generator with trig and gate modes (routable to Pitch, Pulse Width, Cutoff, Resonance, VCA level)
- MS-20 style VCA
- Low power amplifer (scavanged from a Gameboy) and a pair of built-in speakers
There are no CV or gate inputs; instead I just added a simple push button to trigger the EG. I added a 1/4" output jack (so er...I could...errr...
test
it every now and then). She typically uses it with it's built-in speakers, but you really miss out on the low frequency if it's not hooked to a real
sound system. It runs on a pair of 9V batteries that are enclosed in a little box attached to the side. I mounted them like this so we didn't have to open
the entire synth and expose the wiring each time the batteries died.
There are little black dots of magic marker on the face plate for each knob. These are a "starting point" for my daughter. If she ever twists the
knobs to a point where she gets no sound (cutoff too low, VCO tuned ultra-sonic, no CV routed to VCA, etc) she can put each knob at the dot and
get audio again. I designed the faceplate in AutoCAD and printed it on my inkjet printer. I then carefully covered the entire sheet with packaging tape,
and used 3M Super-77 to glue it to the aluminum panel. I then trimmed the edges and holes with an Exacto knife and mounted the panel components.
Considering how cheap it was, I'm very pleased with the results.
Here's the obligatory
audio sample (MP3 - 0:57 seconds - 1,377KB). It was recorded straight to the computer with no effects, then I
cut out a few of the more interesting bits and pasted them together.
