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Clifford Heath Clifford Heath is offline
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Default Taper of Potentiometers

On 26/01/18 15:45, Phil Allison wrote:
Phil Allison wrote:
** Like other senses, hearing responds to *percentage" changes in sound
level.

The ideal volume control produces similar percentage changes for
similar rotations or small movements. Good "log" pots have three
linear sections that approximate the ideal fairly well.

** FYI:

A simple way to get *very repeatable* "log" type curve for audio is to wire the two sections of a dual linear pot in series. The wiper of the first half goes to the top of the second and its wiper becomes the output. Bottom ends are both grounded.

At the centre (50%) position, this reliably gives -15dB attenuation when loading effects are taken into account.


Hah! Square-root taper
Probably good enough for rock-n-^H^H^H^H^Haudio

If you know the source and load impedance of the pot,
wiring a linear pot with the input to the wiper and
output from the top gets you somewhere close to the
same effect.