[LAD] panning thoughts

Arnold Krille arnold at arnoldarts.de
Fri Nov 12 22:45:56 UTC 2010


On Friday 12 November 2010 17:47:08 gene heskett wrote:
> 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. ;-)

Even faster: Use a pre-computed value of pi/2 or pi*0.5. I don't think 
compilers will already optimize such a constant part of an equation.

Arnold
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