Potentiometers, or “pots” to electronics enthusiasts, are differentiated by how quickly their resistance changes. In linear pots, the amount of resistance changes in a direct pattern. If you turn or slide it halfway, its resistance will be halfway between its minimum and maximum settings. That’s ideal for controlling lights or a fan, but not necessarily for audio controls. Volume controls have to cater to the human ear, which isn’t linear. Instead, logarithmic pots like these ones increase their resistance on a curve. At the halfway point volume will still be moderate, but it will increase sharply as you keep turning up the volume. This corresponds to how the human ear hears. Using a log pot therefore gives the effect that a setting of full volume on the control sounds twice as loud as a setting of half volume. A linear pot used as a volume control would give large apparent changes in loudness at low volume settings, with little apparent change over the rest of the control’s range.
First, the 10K Singular Log Pot (above) is a two-in-one, good in a breadboard or with a panel. It’s a log taper 10K ohm potentiometer, with a grippy shaft. It’s smooth and easy to turn, but not so loose that it will shift on its own. We like this one because the legs are 0.2″ apart with pin-points, so you can plug it into a breadboard or perfboard. Once you’re done prototyping, you can drill a hole into your project box and mount the potentiometer that way.
Secondly, the Panel Mount 10K Dual Log Potentiometer (above) is a dual-ganged potentiometer that will satisfy all your stereo-signal needs. Instead of just one potentiometer, you actually get two separate pots, ‘ganged’ together. Turning the grippy shaft twists both standard logarithmic-taper 10Kohm potentiometers. It’s smooth and easy to turn, but not so loose that it will shift on its own.
Unlike some of our other potentiometers, this Dual Log one is not breadboard-friendly. The pins are about 0.2″ apart so it will fit into a breadboard, but the two rows are close together so you’d short the two halves. Thus, we suggest soldering wires to the pins as necessary, using these in a perf-board that doesn’t have the rows connected, or designing a custom PCB.
Once you’re done prototyping with either of these, you can drill a hole into your project box and mount the potentiometer using the included washer and hex nut. We’ve got plenty of matching T18-splined knobs that you can pair up.
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