As musicians, most of us are a little tone crazy. Even though we might be getting a good sound out of our instrument, we just know that it could be better. There are many different elements that contribute to an instrument's tone, but the place most people start when they're dissatisfied with their sound is the pickups.
But how do we know which pickups will be right for us? There are dozens of manufacturers making countless different designs. In addition to the enormous number of options available, the sound one can expect from these pickups are described in terms like “bright”, “warm”, and even “round”. Who knew that tone could be described with shapes?
How much does the average musician know about pickups? Do you know what they're made from and how they work? To most, they are a puzzle inside a riddle within an enigma but that doesn't stop us from dropping a hundred £'s on one in the hopes that it will finally find 'that' sound.
The truth is, pickups are incredibly simple devices that have much more in common with each other than differences. Let's start with the basics...
Fundamentally, pickups are magnets and wires. That's it. Basically, a length of wire is coiled around a magnet, and when a guitar string vibrates within the magnetic field it causes the coil to generate a voltage. This is the signal that your guitar or bass amp amplifies. Pretty simple so far, right?
Let's look at some of the variables that are involved:
Stronger magnets create a hotter signal, and the type of magnet also affects tone. Original Gibson PAF's are one of the most sought after sounds, and most people attribute their trademark tone to the Alnico magnets that were used. For this reason, Alnico II is often used in “vintage” replacement pickups, as they're thought to produce a vintage sound. Also common is Alnico V, which is slightly stronger, and produces a brighter, “punchier” tone. Ceramic magnets are stronger yet, and are commonly used in more modern, rock-oriented pickups.
Increasing the number of windings in the coils increases the output as well, but it also tends to accentuate the midrange while attenuating the lows and highs. As the number of turns increases, the tone gets muddier. Using a heavier gauge wire produces similar results.
Those are the basic building blocks of pickup construction, but another aspect of their design that greatly affects tone is the number of coils. Fender Strats and Teles historically sport a single coil design, as described so far, which tend to have a “bright”, “twangy” sound. But one shortcoming of the single coil pickup is it's tendency to pick up the 60 cycle hum produced by most electrical circuits – building wiring, lights, etc. In 1955 a Gibson employee named Seth Lover invented the Humbucker pickup. The humbucker has 2 coils wound with opposite electrical polarity and reversed magnetic polarity, which has the effect of canceling the hum produced by each individual coil. Due to the larger number of windings, and extra magnets, the effect on the tone is to generally produce a "fatter", more “midrangey” sound.
So what is it about the huge selection of replacement pickups on the market, ranging from inexpensive generic substitutes, to handmade “boutique” options that set them apart? Not really a whole lot, as you can see. In the end, after you absorb all of the hyperbole and metaphors, you just have to know what you're looking for and, most of all, trust your ears.
Guitar Woods
Historically, guitars have been manufactured from a rather narrow selection of what luthiers and builders describe as "tone woods". Of course, there are exceptions to the rule, but the majority of guitars and basses are manufactured from a few tried and true woods. There are many characteristics that make certain woods more desirable for guitar construction, including weight, density, stability, appearance, etc. Let's take a look at some of the more common varieties.
Body Woods
Alder is the classic Fender body wood. Though other woods, like Ash have been commonly used by Fender, Alder has been used since the very beginning, and is considered by many to embody the standard Fender sound. Alder is fairly light in weight and produces a full bodied tone with mellow highs. Due to its subdued grain and fairly light color, Alder is generally finished in solid colors, with the exception being "burst" finishes, like Tobacco and 3 color sunbursts.
Ash comes in a couple of distinct variations for guitar construction. Northern Ash was common in late '60s and '70s Fenders. It's a dense, heavy wood, which produces a bright sound with a strong attack. Hard Ash bodied '70s basses are revered by some for their bright "slap" sound, as popularized by Marcus Miller. Swamp Ash is considerably lighter, and produces a livelier, more responsive tone. All varieties of Ash feature a pronounced grain pattern that looks great with a clear or semi-transparent finish.
Mahogany is most often associated with Gibson instruments like the Les Paul, SG, Firebird, etc. It's a heavy, dense, and very stable wood characterized by a thick, compressed midrange, lots of lows, and warm highs. Many Mahogany instruments are coupled with a Maple top to enhance its normally muted treble response. Due to its density and stability, Mahogany is one of the few woods that are suitable for both bodies and necks. It's dark brown color and uniform grain pattern is appropriate for transparent or solid finishes.
Maple is generally considered too heavy and dense for an entire guitar body, but it is often used in combination with warmer sounding woods to increase treble response. Flame, Quilt, and Birdseye Maple are in high demand for guitar tops due to their beautiful, almost 3 dimensional grain patterns, and can be found on many high-end instruments.
Neck Woods
The same qualities that make Maple a poor choice for entire guitar bodies make it one of the most common and desirable materials for necks - strength, stability, and density. Eastern Hard Rock Maple is the most common variant, and can be found in most bolt-on neck guitars. Flame and Birdseye necks are often used to dress up custom instruments. Maple is a common fingerboard material as well, and provides a bright, snappy tone.
Due to its density and stability, Mahogany is a common material for guitar necks; particularly glued in or "set" neck guitars. However, due to its porous nature it makes a poor fingerboard material.
Rosewood has long been in demand as a fingerboard material, and supplies of good quality wood are becoming increasingly hard to find, and therefore more costly. It's a heavy, oily wood that looks great, wears well, and imparts a warm, complex tone.
Ebony is a very dark, hard wood, and makes an excellent long-wearing fingerboard material. It features a bright attack similar to Maple, but with more lows and mids. Some varieties are black, with others exhibiting prominent brown grain. The latter is commonly stained a uniform black.
Thus concludes our wood primer. As you can see, the decisions made when selecting the materials that go into a guitar have an impact on almost every aspect of the instrument. It's not just about what looks good with what, it's also about the stability and sound of the assembled guitar. The qualities of the various woods discussed here are what have made them desirable to builders and players for decades, and explains their continued popularity.
Selecting The Right Potentiometer
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, 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 pot, humbuckers get a 500k 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 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 potentiometer 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 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 potentiometer 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 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 potentiometers determining the overall sound of an electric instrument. The earliest Telecasters® utilized 1meg ohm 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 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 pots come in. Log is short for Logarithmic and is quite often referred to as Audio Taper or A Taper. Log 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 pots you see on our site are Logarithmic.
Hopefully, this guide explains why certain value pots are used with certain pickups and arms you with the knowledge necessary to experiment with some non-traditional alternatives. For replacement pots, check out our Electronics section. You will find top quality replacement pots from CGE and CTS (as used by Fender since the early 60s').
