Re: loop subtraction

[Chris Chovit <cho@newdream.net>]

Interesting....It seems like you would have to do a FFT to do this, which
would probably best be done in the digital domain, and require some serious
processing power to perform it in real time...

Perhaps there would be a way to just make the "subtrating signal" out of
phase with the main signal, and this might create a similar effect, as the
signals would cancel each other.  I can imagine the usefulness of
this....loops can get pretty busy, and you could "thin it out" using this
method.

Maybe it could be done within an echoplex:  have an insert mode =
"subtract", in addition to the reverse and other insert modes.   Kim, any
new versions of the software in the planning stages?

- Chris



>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


-----------------------------
Chris Chovit
cho@newdream.net