Guitar pots - Guitarists are notorious for their “do-it-yourself” attitude towards instrument maintenance and customization. Most of us won’t hesitate to take our guitar apart at the first opportunity if it means avoiding prohibitive bench fees at the local repair shop. There are definitely conditions that call for professional intervention, but with a little bit of knowledge there’s no reason that many of us can’t handle some of the simpler tasks involved in maintaining, repairing, and customizing our guitars.
Replacing guitar electronics is a fairly straightforward task that can be successfully handled with minimal effort. All you really need are some basic soldering skills and you’re ready to go. Most conventional guitar circuits consist of pickups, switches, guitar pots, capacitors and a jack. The hardest part is determining what value of potentiometer you need for your instrument. With that in mind, let’s take a look at some of the determining factors that will help you make an informed decision when it comes time to replace a volume or tone pot.
Basic rule of thumb goes like this: single coil pickups get a 250k guitar pot, humbuckers get a 500k guitar pot. Why is this? The higher the value of the pot, the brighter the sound, so higher value pots are used with humbuckers to allow a bit more high end to get through with what is, by design, a warmer sounding pickup. Lower value pots are used with brighter sounding pickups to tame some of the extended high end that is associated with single coils.
The Effect Of Guitar Potentiometer Values In Relation To Output And Tone
As a potentiometer is turned fully down, all of the signal from the pickup(s)is diverted to ground, resulting in no output from the instrument. When the guitar pot is turned up to full volume, the resistance of the potentiometer theoretically prevents any of the output signal leaking to ground, and weakening the output signal. Lower value guitar pots, however, do not completely block the signal from leaking to ground even when turned up all the way, so using a 250k potentiometer will result in a slight loss of high frequency, as well as volume. This may please some musicians who want a mellower tone, but for those seeking ultimate purity of signal, a higher value guitar pot may be just what is needed. The higher the value, the more leakage is blocked from ground, which allows more of the signal to be sent to the output. A 500k guitar pot may be just right, but a 1meg ohm pot will provide an all out sonic assault. Higher highs; lower lows; more volume – a rocker’s dream! The only drawback of going to this higher value is the perceived range and sweep of the control. It’s like going from 0 to 10 without the fine increments of control in between.
The Telecaster is a good example of guitar potentiometers determining the overall sound of an electric instrument. The earliest Telecasters utilized 1meg ohm guitar potentiometers. They were deemed too bright to be practical for a wide range of musical styles. As a result, the potentiometers were changed to 250k to “bleed off” some of the extreme treble “twang” that the early versions were known and loved for (Stratocasters also use 250k guitar pots for the same reason). Some Gibson laptop guitars had 5 meg ohm pots. Talk about bright!
Exploring Your Options…
To find out if switching to a higher value pot might benefit you, try this simple test: Disconnect your pickup(s) from the circuit, and use some “jumper” wires to connect them directly to the output jack. If the pickups sound louder and fuller, then you will benefit from a higher value potentiometer. If, however, your pickups still aren’t sounding the way you’d like them to, maybe you should take a look at our Kent Armstrong replacement pickups!
Log? Audio Taper? Linear….? A question that we are always being asked is what is the difference between Linear and Log pots? Linear pots increase the impedance evenly as you turn them up. So, if you were to turn a Linear pot from 0 up to 5 (in other words from off position up to mid way) then the impedance is increased by half. However, the human ear doesn’t actually hear this as a gradual volume increase, instead it sounds like nothing much happens for most of the sweep and then all of a sudden there is a huge jump in volume. This is where Log guitar pots come in. Log is short for Logarithmic and is quite often referred to as Audio Taper or A Taper. Log guitar pots are used specifically for audio applications and are adapted to the human ear so that the entire sweep of the pot sounds like a gradual increase, offering a greater degree of control and accuracy when used on a guitar or bass. Most guitar manufacturers use Log pots for both volume and tone controls on their instruments and they are by far the most popular choice amongst musicians when purchasing replacements. This is the reason why most of the guitar pots you see on our site are labelled as having a logarithmic taper.
