One of the most important aspects of a guitar’s overall sound is by far the pickups. When these things were invented in the earlier part of the last century, it not only gave birth to the electric guitar but also immeasurably changed the history of popular music. Over the years, pickups have evolved as rapidly as the music they help create. The first were simple single coils that did their job of getting a guitar to work through an amplifier but were often a bit too noisy. Humbuckers came around and a did much to help in the noise department, but required two coils instead of one, meaning they wouldn’t fit on all guitars, such as the popular models at the time – the Fender Telecaster and Stratocaster. As time went on, single coils became less noisy and more refined, humbuckers came in all shapes and sizes, new variations of the two and brand new implementations began being experimented with; some became active, some became hot and some just kept it vintage. With that in mind, there are still several out there unaware of a few of the more popular modifications that have come to pass in the world of the guitar pickup. Some of these are a little minor while others completely changed the game, although each step was just as important in getting us where we are today in terms of pickup technology. So, for those of you in the mood to brush up on some of the finer points of pickup renovation, read on and check out some of the brightest changes of the electric guitar pickup.
Just in case some of our younger readers are unaware of the basic principles behind how pickups work, they are essentially magnets wound in copper with a core made of alnico or ceramic that that can sense the amount of vibration in the strings. They can do this by reading the amount of shift in the magnetic field caused by the vibrating strings and converting it into an electrical signal that can be used by the amplifier. There are more specifics to it, but that’s pretty much the gist of it, unless you’re talking about active pickups, but more on that later.
The Humbucker Pickup
One of the earliest problems with the electric guitar pickup has always been their propensity of being affected by electrical interferences. The interference can come from anything that uses alternating magnetic fields such as transformers and power supplies – pretty much most things that are electrical. When pickups pick up the strings vibration they also pick up some of this interference, and although it might be slight at first, the more this signal goes through other electrical devices such as an effects pedal or amplifier, the more the interference grows, resulting in a very noticeable hum from the amplifier during the silent sections of songs while the guitar is not in play. Humbuckers were invented to take care of just that.
It all came about when applying the principles of “common-mode rejection,” which is essentially an electrical device’s tendency to reject the same common signals coming from two different leads. Humbuckers use two single-coil pickups to achieve the two different leads requirement. They are placed right next to each other but in such a way (with the copper wires of each going in opposite directions; one clockwise, one counter) that the “hum” signal is replicated, thereby canceling itself out by the time it hits the amp. Check out the principles of electrical engineering for a deeper sense of how exactly common-mode rejection works.
The Hot Pickup
Alright, this isn’t necessarily a specific kind of pickup but used more for categorical purposes. When someone uses the term “hot” for a pickup, they are essentially talking about the signal output being stronger than on a normal pickup. Some might call a certain pickup “hotter” than the other, so they are again using it to compare it to the output strength of the signal when compared to the other pickup. Without getting too deep into the logistics of guitar pickup inductance, your average single coil pickup has less signal output than that of a humbucker, or even that of a single coil bass pickup because in essence it doesn’t really need as much as output as the other two if your goal is simply to play. But let’s say you don’t simply just want to play, but rather want to play with something that requires more power or more specifically a style of music that takes advantage of more power.
Hot pickups send out more output signal which in turn gives it a set of advantages and disadvantages to that of your less hot pickups. Some prefer hot pickups because they control distortion better but it turn will sound harsher when played clean, this is why metal guitar players who rarely play clean prefer a hotter pickup set up. If you were to play a Telecaster and a Les Paul with the same amp and distortion effect, you should hear a thicker bite with the Les Paul as its humbucker pickups are hotter than the Telecaster’s single coils. A higher output signal is also helpful in maintaining signal integrity when playing through a long cable and/or several pedals connected to each other. Critics of hot pickups tend to dislike their compressed sound, claiming they lack the amount of clarity of the standard pickup. This is due to the increased resistance of the output signal which pretty much chokes off the high end tones. Also, too much output signal can cause EQ problems with amplifiers that can’t properly handle the extra power.
The Overwound Pickup
Lindy Fralin Strat Blues Special Hot Pickups
This kind of pickup essentially falls into the category of a hot pickup in that the features of its build give it more signal output than that of your standard single coil; ergo, hot. Overwound pickups are wrapped with more coil than that of a standard pickup which in turn strengthens the impendence of the magnet, increasing the voltage which then increases the output signal, making them hotter than a normal pickup. The advantages and disadvantages of this are what you would expect from a hotter pickup; stronger mid range attack but less clarity of the highs. When a pickup is overwound, the “position” of the resonant peak of the signal is significantly lowered, creating less treble, while the peak at the midrange is increased, meaning a stronger mid. And just in case you don’t know what a resonant peak is, it is the frequency of the signal with the highest output level. The output frequencies of almost all magnetic pickups are never level, but have peaks and valleys in frequency, giving each pickup its own character, in other words, some have better highs, better mids, better lows, etc, and hotter pickups just happen to have their peak much lower than your standard pickup.
The Active Pickup
An active pickup is a pickup that uses electronics to enhance or modify the output signal of the vibrating strings. Unlike traditional pickups (known as passive by comparison) that simply work through the magic of electromagnetism (they can create enough electrical potential needed to create a signal without the need of extra power, although the output is relatively low), active pickups use an external power source, pretty much always a 9 volt battery, in order for them to operate. This is because active pickups use preamps, active filters, active EQ and other tone affecting features, all of which requires juice to work. They are similar to hot overwound pickups in that they give you more output signal which works great when using a lot of pedals but it’s how that signal is strengthened that makes all the difference. Hot overwound pickups strengthen the signal by giving you much more electrical impedance, creating a stronger signal while active pickups strengthen your signal by giving you a much more defined and balanced output and relatively less electrical impedance. Think of the signal strength of a pickup as the amount of light given off by something. Hot pickups will be like a bright flame that dances around and is not too stable while an active pickup is like a laser, not as bright but packs a much clearer and concentrated light. Both mean more power over single coil, but with active, you will get a much more uniform signal without the steep peaks and valleys in frequency that you would get with hot pickups. So again, both will give you higher output, but active will do it with much more control, although this can lead to your tone sounding a bit flat or digital.
One of the reasons that active pickups are so popular with metal guitarists in particular is that they can take advantage of the higher output and are not as worried about the tone, especially if they are playing heavily distorted guitars that pretty much cover up most of the flat sound you get with active pickups. The stronger output is also especially helpful if playing at high gain or high volume in that they will handle much better in these situations than your standard pickup because of their more stabilized and clearer output frequency as well as their noise free nature. In essence, active pickups give you a clearer sound with great signal integrity but in turn will give you a less natural sounding tone that might even sound a bit digital because of their balanced monotonous frequency.
The Search for the Perfect Tone
There you have it, only a small sample of the deeper aspects the guitar pickup. With so many possibilities and variations, it’s no wonder why some might be inclined to stick with their stock set of pickups but for those daring enough to search for their perfect tone, a brand new set of pickups might just be exactly what they were looking for.