Understanding Guitar Pickups: Myths vs. Facts
Posted May 25, 2017
Pickups are an important part of your guitar’s tone, but can often be misunderstood. In this blog, we are going to separate fact from fiction as we dig deeper into the construction of pickups and their specs.
“In their simplest form, pickups can be viewed as the microphones for your guitar strings. Dive deeper and you’ll see that pickups are highly technical physics devices.” - Paul Reed Smith
THE PARTS OF A PICKUP
Let’s lay a foundation of our pickup knowledge by looking at the parts that make up a typical humbucking pickup. We emphasize “typical” because there are hundreds of variations of each of these components - and many pickup manufacturers will approach them in different ways.
READING PICKUP SPECS
*PAUL'S DISCLAIMER: What follows is opinion. I believe if all the pickup manufacturers were in a room, we would disagree about a lot of this. That said, we get a lot of requests to explain our views on this issue, so here we go.
If you’re shopping for new pickups or researching to understand the current pickups in your guitar, certain specs can give you a general idea of how the pickup sounds - but remember these individual specs don’t tell the full story!
Here are the specs that are used the most often and their simple definitions:
DC Resistance: A simple measurement of the total electrical resistance of the pickup. It can loosely indicate how many turns (feet of wire) are in each coil and what gauge of wire was used. And because it is the number you can measure with an OHM meter, it's typically used in our industry as an indicator of how the pickup will sound without using other sophisticated testing equipment. PRS has that equipment. People relate the number to what pickups they've heard in the past (with the same basic number).
Magnet Material: This is a very deep rabbit hole. That said, it is the material that the magnets are made from, the most popular being Alnico 2, Alnico 3, Alnico 4, Alnico 5, and Ceramic. A stronger magnet will create more output.
Covered / Uncovered: This spec should be very easy to tell visually, but pickup covers can make a significant difference in the tone of the pickup. If two pickups have otherwise identical specs, the one with a cover will typically have less treble response.
With this cursory knowledge, lets look at some pickup myths vs facts.
PICKUP MYTHS VS FACTS
MYTH: More DC resistance = more output.
This could be true, but you’ll run into trouble if you assume this is always true. Remember that a pickup is a sum of its parts: the type of magnet, the strength of the magnet, the turns of wire, the gauge of wire, the size of the slugs and screws.
The only way DC resistance = more output is if you are measuring the DC resistance of two pickups with otherwise identical parts and gauge of wire. In that case the pickup with the higher DC resistance (may indicate more turns) will give you a greater output.
The truth is that magnetic strength in combination with turns is output.
MYTH: Bigger the magnet number (Alnico 2, Alnico 5), the stronger and louder the pickup is.
Again, this is mostly true, but the numbers refer to different compositions of material, not the size and shape of the magnet...and not how well the magnet was magnetized. Each material has differing properties that affect a pickup's sound. We said above that a stronger magnet will create more output, this is true, but remember that there are many other factors at play which influence your pickup's total output and sound.
MYTH: The gauge of the wire is more indicative of the sound than the number of turns.
In reality, this is mostly not true. In our experience, turns and wire coating are more important, but that's a long argument between electrical engineers and guitar makers (over a beer).
MYTH: Pickup covers don’t make a difference.
Paul Smith chimes in, "B.S., take the cover off of any old Gibson pickup and tell me it sounds the same." More delicately put, covers disrupt the magnetic field, weakening the treble response of the coils and acting like shortened turns. We design our coils and other components differently when using covers to balance the tonal qualities affected by covers.
How to make electric guitar pickups is a very, very, complicated equation. In the end, plug the guitar in and see (hear) if you like the way it sounds. If you don't like it, don't buy it. If you really like it, you might not want to walk away. PRS is very focused on making the very best pickups we can. We are getting better at it, and the market has been increasingly accepting of what we manufacture.
Stay tuned for Part 2 as we explore PRS pickups and the history behind Paul's designs!