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Logarithmic or linear potentiometers for volume and a 3 band EQ

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Pexy13:
Greetings!

I am in a proces of going trough my junk pile to find all the components I need for a Bass guitar preamp.

Looking at the schematic and the text that was posted about the project I can't find if I should use logarithmic or linear potentiometers.
There should be one for each (volume, treble, bass and mid).

The Scehematic is attached below.

TimFox:
Usually for amplifier controls, the tone controls (treble, bass, and mid) are linear (sometimes center tapped) and the gain control (volume) is logarithmic.  You can make a quasi-log pot from a linear pot with an appropriate load resistor between the wiper and CCW.

Pexy13:

--- Quote from: TimFox on April 06, 2020, 01:44:18 pm ---Usually for amplifier controls, the tone controls (treble, bass, and mid) are linear (sometimes center tapped) and the gain control (volume) is logarithmic.  You can make a quasi-log pot from a linear pot with an appropriate load resistor between the wiper and CCW.

--- End quote ---

Thanks I'll try it out.

basinstreetdesign:
The way that volume pot is configured, a linear pot is good since the relation of gain using the two halves of the pot is non-linear, actually hyperbolic.  Just how well it emulates a log pot is a function of the 47K value against the 10K pot value.  You may have to play with the 47K value to optimize this.
I'm sure this is what the designer was going for, to begin with.

obiwanjacobi:
FYI: the -15V on opamp B is on pin 4 not on pin 1 as shown in the schematic (pin 1 is output for opamp A).
[2c]

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