[LAD] panning thoughts

Ralf Mardorf ralf.mardorf at alice-dsl.net
Sat Nov 13 13:17:46 UTC 2010


On Sat, 2010-11-13 at 11:54 +0100, fons at kokkinizita.net wrote:
> On Sat, Nov 13, 2010 at 09:07:35AM +0000, Folderol wrote:
> 
> > Why not go the whole hog and use a pre-calculated look-up table for the whole
> > thing?
> 
> You only need to compute the L,R gains when they change.
> Using a second order approximation such as the ones I
> poster earlier is probably faster than a lookup table
> in practice.
> 
> Here's one more:
> 
> p = panning position, 0...1
> m = panning law control, 0...1
> 
> q = 1 - p
> d = m * p * q
> L_gain = q + d
> R_gain = p + d
> 
> m = 0 -> -6 dB at center
> m = 1 -> -2.5 dB at center
> 
> This takes three additions and two multiplications, which is peanuts.
> 
> Ciao,

Thank you for your explanations Fons :).

Is there a 'most common value' for the centre?

I do know several analog mixing consoles from el cheapo to very
expensive and all pan pots are ok, I can't notice an audible difference.
I only know one very el cheapo mixing console, the Yamaha RM 602,
http://i1.tinypic.com/6fzx1k1.jpg , where the pan pots are crappy. As a
youngster I started with this mixer :), using the pan pot means to
readjust the faders ;).

Cheers!

Ralf





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