Re: loop subtraction

[landman@wco.com (Mark Landman)]

>Mike McGary wrote:
>>
>> 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.
>

If you had an exact duplicate of your original base pattern, inverted it's
amplitude, and mixed it at 50% with the loop, while playing it back
precisely in time/phase with the base pattern, that would do the trick.
Kinda hard to do thoughŠ

This brings up the interesting question of how to "bring the loop back
down", it's easy to quickly build a formidable wall of sound, but much
harder to elegantly thin it outŠ

DSP filters and processes in the feedback loop would do this, as well as
multi-track loopers. Any other suggestions for ways to do this?

Mark