[LAD] Half-OT: Fader mapping - was - Ardour MIDI tracer

[Fons Adriaensen]

On Thu, Aug 21, 2014 at 08:06:13PM +0100, John Rigg wrote:
 
> http://www.pennyandgiles.com/Products/Audio-Faders-Video-Controllers/Linear-Manual-Fader-PGF8000.aspx
> 
> The Panel Graduations/Slots diagrams on page 3 show the taper characteristic.

The taper I'm using in some apps is very similar:

<http://kokkinizita.linuxaudio.org/linuxaudio/faders.png>

A position vs dB plot of this consists of two parts: the top
one (down to -20 dB in this case) is linear, the bottom half
is parabolic. The two curves are tangent at the intersection
point, so there is no 'jump' in the dB/distance ratio.
Mapping functions in both directions are very simple.

Ciao,

-- 
FA

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