Thursday, September 27, 2007

Tape speed sequencer

A sixteen-step sequencer on a computer controls the speed of a motor in a tape cassette machine.

The controls on the virtual sequencer include speed (how quickly the different steps are read through), length (how many steps are there in the looping sequence) and the actual sequencer itself. The lower a given step is on the sequencer, the lower the speed of the motor is in the tape machine at that point in time.

A special thanks to Edward Kelly for re-igniting my interest in tape control and manipulation.

Video URL:

The music in the cassette player is once again just Drowning Goldfish having a jam. Featuring David Gustafsson on guitar and bass, Brent Easson on drums and myself on bass and guitar.


Anonymous said...

I've just started with arduino, and trying it out on floppy drives and salvaged cd player motors. The slow start and stop isn't always what I want.
My idea would be to LookAhead in the step list, see how much lower or higher the next step is, if next value is lower: reverse voltage at the end of the step as a break, if next value is higher: apply full PWM value for faster speedup. Also have a StepDifference value, updated each step, to use as an equivalent to an Envelope to ease tapespeed to required value.

All this in a 16th of a measure may be overkill, havn't tried this yet. I'm so slow in coding and debugging, but so far it seems that reversed voltage CAN force the motor to an ermm... faster slowdown. Or reverse direction. Startup lags even with full voltage applied.

Well, first I will continue tracking down all your sketches to download them. They're great, thank you for sharing.

Sebastian Tomczak said...

Thanks for your comment. Sounds interesting. Perhaps you would also like: