another instrument i made recently: a musical
instrument inspired by the optigan (a light-tone instrument and a kind
of predecessor of the sampler).
my instrument generates the tone with a light depended resistor which
kann be controlled by an LED. the speed and patterns on the disc
determine the frequency and shape of the resulting wave form.
currently it has 8 keys (8 different pitches) and a manual pitch bend.
the instrument was made from an old cd-walkman 8 LDRs & 8 LEDs plus
some passive components, 8 switches and voltage regulator.
UPDATE: more info like schematics & code after the break.
disc images. just print them on some transparencies cut them and play them:
discs.zip
is the 5501 in the schematic a
HCPL-5501 - Hermetically Sealed, Transistor Output Optocouplers for Analog and Digital Applications - Agilent(Hewlett-Packard)????
Hi!
This is a great instrument!
When you say LDR do you mean Photocell or Photodiode? You amplified the sound with an audio ampli or you built a Op Amp?
Thanks!
no i used light depended resistors but actually photodiodes or photocells might be better. there's no op-amp involved. the signal is only amplifyed by the amps of the mixing desk.
you should be able to use a 9v power supply but you might need to adjust the resistors of the LEDs. it works through the rotation of the transparent and printed disc. search for "optigan" in the web...
