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Phil Allison[_3_] Phil Allison[_3_] is offline
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Default Taper of Potentiometers

Clifford Heath wrote:


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

** Is that what it's called ?

Probably good enough for rock-n-^H^H^H^H^Haudio

** It's so repeatable, unlike with some batch of low cost log pots, you could have the -dBs figures printed on a front panel and they would always align with the pot.

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.

** Horrible idea - it shorts the signal at low settings and sends the output impedance high just when you want it low for noise/hum reasons.

...... Phil