Why do companies mass produce sets labeled as “custom guitar pickups” when they’re clearly not? And what actually makes a pickup custom? Is it just any brand that’s not DiMarzio or Seymour Duncan? If so, then why does Seymour Duncan have a custom shop?
The Tonal Factors
The word ‘custom’ gets thrown around a lot as a marketing buzzword for guitar equipment. You see the word included in product titles for virtually anything…I wouldn’t be surprised if there were some Custom Strap Button Screws out there. The word implies uniqueness in my book, so when I see a mass-manufactured big-brand ‘custom’ guitar, I get annoyed. It’s just a different guitar.
In the case of pickup companies, the word is implying that the winding or magnetic posts are different from the norm. But with virtually every combination of components already branded and available to buy, the ‘norm’ has to be a standard related to how the parts are put together – particularly the winding.
You’ll see companies racking up 10 bobbins at a time and turning on an automated winding machine to churn out identical sets. The shame in this isn’t that it’s somehow a worse tone, but that there’s so much more variation in the sound of a pickup that’s wound one at a time or by hand, and the imperfections in technique can produce something entirely unique.
There’s quite a bit of variety to be offered from a part that’s comprised of so few pieces that affect the tone. In fact, switching your pickups is the most significant tonal change you can make to an electric guitar before the output.
The Winding Defines Custom Pickups
Typically, pickups are wound by machines that count the exact same number of turns, repeat the same pattern of lateral movement, and use copper wiring of a consistent gauge and insulation material/thickness. Manufacturers are well aware of the factors that go into shaping a pickup’s voice but the need for a model’s consistency will prevent less precise winding techniques (tension, patterns) from being used, which is actually the primary reasoning for buying a set of custom pickups in the first place.
The basic principles are still taken into account; more winding = more output, darker tone, and easier breakup. Particular gauges and insulations have resistance levels that can be calculated and the sum of a pickup design’s specifications can give a fairly accurate description of how a pickup may sound before it’s made – even when there’s so many materials and gauges to choose from.
Insulation
There are almost 20 different types of insulation: polyurethanes, nylons, poly-nylons, polyester, Teflon, Formvar, plain enamel, etc. The amount of DC resistance is the most important statistic when trying to measure the tonal effect of different insulation materials. The thickness of the insulation material will add another factor in the amount of resistance. The tonal differences are due to the insulation’s resistance, which affects the overall capacitance of the coil. Heavier insulation can maintain more high-end detail.
The Way of the Wire
The way the wire is wound affects the amount of capacitance in the signal that helps shape the pickup’s voice. If you’ve read the article on understanding capacitors, you know how much of a difference this can make. Some of the larger companies have had the opportunity to observe how variations in the wrapping pattern can be used to steer the pickup’s tone one direction or another, which is quite impressive.
But more impressive is the fact that someone without a clue could wind a pickup by hand and create something spectacular and unique that a larger pickup manufacturer would have difficulty recreating simply because of the lack of control in the winding process. The tension held on the wire, the lateral movement and distribution pattern during the wrapping, and little loose spots are going to affect the tone much more than you may expect.
These sound like mistakes and sloppy work, but it actually often creates a harmonically rich voice that can be as intricate as the thousands of wire wrappings that built it. Variation in the winding process is what separates a ’boutique’ or ‘custom’ pickup manufacturer from a larger one. That doesn’t mean you can’t call up Seymour Duncan and ask them to build a set to your specifications, they will fulfill requests for custom pickups.
Alternate Wire Materials
Silver is used occasionally, and has a significantly different tone from copper. Silver is said to be the only metal with a lower DC resistance than copper. The tone is much more harmonically diverse, has a quicker attack, and is generally just more responsive than copper. Unfortunately, it’s too expensive to be a practical material for mass-produced pickups.
Magnets & Pole Pieces
Different magnet types can affect tone as well as the output depending on strength. Alnico magnets are made from a combination of nickel, cobalt, and aluminum. Ceramic magnets are made from iron and a few different earth metals compressed together. There are a few factors that will change the shape of the magnetic field and the way the string’s vibration is inducted – the magnet’s composition, the spacing of the pieces, use of a single ‘blade’ magnet, and use of pole pieces attached to a magnet.
Generally, we can say that Ceramic magnets are stronger and higher gain than Alnico magnets, and that Ferrous Steel poles give you a wider/looser tone. Pinning down the tonal differences is a little more complex though, due to so many variables – the chart below should help when it comes time to make a choice:
| Strength | Bass | Midrange | Treble | |
| Alnico II | 2 | 3 | 1 | 2 |
| Alnico III | 1 | 3 | 3 | 2 |
| Alnico IV | 3 | 3 | 2 | 3 |
| Alnico V | 4 | 2 | 1 | 4 |
| Alnico VIII | 5 | 2 | 3 | 5 |
| Ceramic | 6 | 3 | 4 | 4 |
| Description | |
| Alnico II | Smooth, “Vintage” – Soft attack |
| Alnico III | Pronounced midrange, “Vintage” – Very soft attack |
| Alnico IV | Flat, even response – pairs best with specific instruments |
| Alnico V | Tight low-end, sharp/bright highs – Strong attack |
| Alnico VIII | Tighter low-end, high output, aggressive mids |
| Ceramic | Tightest lows, high mids/highs – best with over-wound sets – Sharp attack |
I’m sure there’s a lot of differing opinions out there from pickup manufacturers, so the best way to truly know is to hear each of them on the same instrument with the same pickup specifications…which is a pretty immense task to arrange. Maybe I’ll see if I can make recordings for comparison some day though – I know Seymour Duncan has a few available on their site, but it’s not a wide selection.
Wax Potting
When the pickup is dipped in wax it will reduce feedback simply by keeping the pieces from shifting around and vibrating against each other. In most cases, particularly with people who are playing with high-gain amplifiers, this is necessary.
Purposely having the pickup un-potted allows microphonic sounds to be picked up from the air within the pickup’s magnetic field and amplified along with the string’s vibrations. This is pretty much only found in older pickups and vintage-style single-coil pickups, and can be the deciding factor for some – it’s a prominent difference in tone.
And now you have a very solid base of knowledge to make informed decisions the next time you want to buy a set of custom guitar pickups or even build your own…that’s for another article though!
