Sound examples (mp3):

  LDR sweep
  overtone chaos
    The soundexamples are recorded from the line out of a bass guitar amp, and afterwards digitally enhanced with a bit of equalizing (bass boost) and a discrete amount of reverb.


A 'Bon Tempi' version of a common drum toy that comes in a variety of shapes, but with (almost) the same features. Four drumpads and a start/stop button for a 'demo' auto rhythm, that plays variations for two bars when drum pads are pushed while the rhythm is playing. The circuit inside was a 'black blob' with nothing more than one timing resistor to mess with. Painted in metallic black.


Speed/pitch: A potentiometer placed instead of the original timing resitor makes speed/pitch variable from grinding slow to furious fast.

Lightcontrolled pitchbend: A light dependant resistor is placed in series with with the potentiometer to give lightcontrolled variation of pitch/speed. Changing the amount of light that reaches the LDR, by moving your hand above the LDR or waving the BabyDrum around, is a fun and bodily intuitive way of playing the BabyDrum. A toggleswitch lets the LDR be bypassed.

Line out: A line out 6,3mm jack socket in parellel with internal speaker. Output level can be adjusted by a small trimmer potentiometer mounted inside the box. Through a hole next to the jack socket, it can be turned with at small screwdriwer.