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Monthly Archives: January 2009

this a quick preview of what I’m working on at the moment…a simple sequencer using one 555 as  clock, one 4017 as sequencer, and one 4016 as relay…to control 4 basic toy circuit drum sound,; it’s going to be a 10steps max sequencer with 4 different sounds possible for each step. no polyphony—here is a video and a drawing of what I’m thinking about…after this will try more complex designs…. but this is a god start…




let’s start with a video:

(thanx again for the recording to LucySombra):

I made this project a year ago, using the mechanics of  (his master’s voice) old Victrola, found on the streets of Barcelona, by jan (thanx again man) and brought to me to salvage it’s still usable parts, the poor thing had ended it’s life as a record player on the trash, needle and arm missing, cone sound missing, etc… BUT the only one thing remaining, and the most important to me was the cranked  spring engine, with it’s old school system to keep speed regular…

seqenciador mechanico

The result is a very interesting cranked beat sequencer,  it has four radial channels, with 24 steps each, each step is one hole on the plate, where small plastic pieces (from “mastermind” game, also trashed out from bcn) can be placed to trigger a sound. Each channel is aligned with a momentary switch which when contacting one of the plastic pieces triggers the sound assigned to that channel.



There is two different circuits that can be used interactively with each other. On one side a simple drum toy with four drum sounds, some basic bending like pitch control (for all the sounds at the same time), and body contacts for distortion mode 1 and 2, and in the other side a simple pitch controllable oscillator circuit for each channel, (made with just one  4093).


it’s is an open sequencer because any source can be triggered by plugging it’s push button trigger poles  to one of the rca connectors on the back, that is how the drum toy circuit encased in the box is triggered. that also means than the sounds triggered by each channel can be easily swapped on the fly by others by just plugging the desired source on the desired channel.



on the other hand both circuit’s have independent volume control to be able to tune the mix levels, some times oscillators can be loud… the yellow buttons also trigger each channel for longer manually operated notes.