A little roundabout in its sound design, this actually uses an unpitched sawtooth to provide an impulse for a highly resonant filter. The trigger from a MIDI note strikes the VCA, which passes audio to the filter, whose frequency tracks pitch, producing tones reminiscent of a toy piano (in some settings… in others it sounds a bit like wooden blocks and in others still it sounds like nothing of note).

I also wanted to try using all eight notes of polyphony available to ZOIA–in most instances, it’s not the best use of CPU, but this sound generator was cheap enough that I got eight voices and a nice delay with mod module adding some space.

It works best from C4-C8, and the best range for ‘toy piano’ is probably C5-C7. Below C4, it gets very bass-y, and the brightness fades. That said, there are some deep, sub-bass sounds available there.

Adam Sadowski from the FB group got me thinking about this. It’s not quite an electric piano, but maybe it

Controls:

Left footswitch: momentary. Momentarily sets the resonance of the filters at 100% (it acts somewhere between a sustain and a brightness).

Middle footswitch: latching. Turns the delay on and off (by adjusting its mix from the front panel setting to 0%).

Right footswitch: latching. Sends the delay feedback to 100%, creating a little loop.

Front panel:
[RS]…………………[MR]………
…….[DM]…………………[MD]
……………[DT]…………………..
…………………..[DF]……………

RS — resonance. Sort of a combination of sustain and brightness. At 100%, notes sustain fairly long. As it drops, they become more percussive. ~.8-1 = toy piano settings. ~.6-.8 = wooden blocks and other pitched percussion with very short sounds. Below this… well, find out. (On lower octaves, it has more use, as lower-pitched notes can sustain for some time without attenuation.)

DM — delay mix.

DT — delay time.

DF — delay feedback.

MR — mod rate (for delay).

MD — mod depth (for delay).

MIDI channel 1, priority newest. Velocity is enabled. This controls the duty cycle of the sawtooths, and it has a very subtle effect on the brightness of the sound. (I thought about tying it to filter resonance, but I decided otherwise, since my favorite setting is with the filters maxed at 1.)

Sound clip:
0:00-0:27 — resonance at ~.8 for a shorter sustain. You might hear a “chirp” from one of the later notes–there’s a little glitchiness that comes through the filter every now and then (I think it has to do with where in the sawtooth’s cycle the VCA opens, but I’m not sure).
0:28-1:10 — resonance at 1. It ends up somewhere between a toy piano and vibes (and maybe a bit synthetic, but I like it!).
1:11-2:00 — delay on (resonance at about .85, if I remember correctly). I play around, then loop the delay, finally I allow it to empty by unlatching the stompswitch.
2:00-2:20 — some of that deep bass (use headphones!)
2:20-2:33 — “wooden block” sound, with resonance at ~.6.