Re: loop subtraction

["Matthew P. Davignon" <mdavig@sfsu.edu>]

Terry Riley invented something like that. It was essentially a multitrack
tape looper. A San Francisco musician named Paul Drescher built a very
similar system with 4 tracks and a footswitch for each track. You could
probably build one from a four track reel-to-reel without too much trouble.
It might take some design to work in footswitches, variable loop lenghtt,
etc..

Matt Davignon

Mike McGary wrote:

> Just a thought....
>
> Long ago I worked with an FFT that would show you a
> graphical depiction of the current sound source (SoundForge
> has this in their 4.5 version).  One of the features of the
> hardware FFT was the ability to 'subtract' sounds.  If you
> had a sound that had an overpowering 600hz section, you could
> put it in subtract mode...play a 600hz sound....and the
> resulting sound was the original minus the 600hz sound
> (kind of a follow-me EQ...)
>
> Wouldn't it be slick to have a looping device that allowed
> this?  You start a base pattern....play some parts on top of it
> and build it's thickness....and then 'subtract' out the base pattern
> by playing it again.
>
> (excuse my ignorance if there is already a device like this and everybody
> already knows about it....slap me if my echoplex already does it)
>
>             -Mike McGary