[LAD] panning thoughts
gene heskett
gheskett at wdtv.com
Fri Nov 12 16:47:08 UTC 2010
On Friday, November 12, 2010 11:43:42 am Eric Kampman did opine:
> On Nov 12, 2010, at 1:40 AM, Jens M Andreasen wrote:
> > On Thu, 2010-11-11 at 20:22 -0800, Eric Kampman wrote:
> >> Since power is proportional to signal squared, this means ..
> >> .. L(t) = cos(t * pi / 2) and R(t) = cos((1 - t) * pi / 2)
> >
> > I think you misspelled one sin(), no?
>
> No, turns out the 2nd equation is equivalent to sin(t * pi / 2) I think.
And is computationally less expensive if you drop the pi / 2 and use
pi * 0.5 as mulls cost less than divs. Or at least this is true if its not
handed off to an FP processor. ;-)
> > It is a complex mul you really want - where L+R is the real and L-R is
> > the imaginary. You can have the sin/cos pair very cheaply by using an
> > LFO that works by rotating iself by some complex constant.
>
> Great idea. Will use. Thanks.
--
Cheers, Gene
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Don't get suckered in by the comments -- they can be terribly misleading.
Debug only code.
-- Dave Storer
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