Phil Allison har bragt dette til os:

DJ mixers have a "cross-fader " that allows a pair of stereo channels to be
mixed in any proportion. Most DJs work the ring of the things - so much so
that it is standard practise make the cross-fader a "user replaceable" module
fitted on sub panel that slots into the main panel.

Are anyone using an optical fader, where moving the fader allows more
or less light to a sensor, controlling the fading?

Or should I file a patent claim? :-)

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