The copper coil and steel guitar strings are placed inside that magnetic field.
The magnets in the bobbin create a magnetic field (or multiple magnetic fields). The direction of the coil winding is called the pickup’s “phase” and is a crucial part of how pickups work together. The beginning of the coil is soldered to the (usually) black wire, and becomes the “Negative” or “Ground.” The end of the coil wire is soldered to the (usually) white wire, and is considered the “Positive” or “Hot.” If the pickup is wound clockwise, it is considered “Standard Wound ” if it’s wound counter-clockwise it is “Reverse Wound.” The CoilĪ very thin, (usually) copper wire is wrapped around the bobbin thousands of times to create a coil. The direction of the magnet, North Up or South Up, is called the pickup’s “polarity” and it’s a crucial part of how pickups work together. Alnicos are often the go-to magnets for higher-end pickups, and several great-sounding ones have been produced using them, including the Gibson ’57 Classic. In the bobbin, six alnico magnets shaped like posts are used instead of the machine screws, and no bottom bar magnet is needed. The properties of alnico magnets tend to give pickups a warmer, more organic sound than ceramic pickups, but often at the price of a lower gain output. Alnico magnets conduct electricity and they are usually more expensive than ceramic magnets. Many great-sounding ceramic pickups have been produced, however, and they’re worth checking out, including the Seymour Duncan SH-6 Mayhem.Īlnico magnets, also strong and permanent, are made from melting together and casting aluminum, nickel, cobalt, (al-ni-co), and iron. Because the brightness of the ceramic pickups can lead to a sound that is harsh and brittle, guitar players sometimes dismiss them altogether. In the bobbin, the ceramic magnet is usually a bar that lays at the base of six machine screw posts that are spaced to match the strings. This type of magnet does not conduct electricity, it’s cheap to build, and it usually leads to a bright-sounding pickup with high output. The iron oxide is mixed with nickel, zinc and/or a few other elements, and baked at high heat to produce the ceramic magnet. We go over each type of magnet and the effect it has on tone, in our Build Your Own Pickups article, but in this one, we’ll just discuss the two most common types: ceramic bar magnets and alnico post magnets.Ĭeramic magnets are strong, permanent, and made mostly from iron rust in the form of iron oxide. Magnets are essential to bobbins, and there are several types, each having specific qualities. The main purpose of the bobbin is to provide a structure to wrap the copper wire coil around, and to provide housing for the magnets, steel posts, attachment screws, etc. Oftentimes, the bobbin is made from a non-conducting top and bottom, held together by six magnetic posts, or machine screws, with a bar magnet on the bottom, but bobbins can come in all shapes and sizes. The bobbin is usually made out of plastic or fiberboard, but it can be made from cardboard, wood, or anything non-conducting. In a single coil pickup (double as well), there is what’s called a bobbin. We’ll start with the parts, then move into the ways the single coil and double coil pickups actually work.
We’ll discuss the single coil first because it’s the original type and it has a simpler design. Then we’ll examine single coil and double coil pickups, the differences between them, and why you would want to use each type. In order to understand what we are talking about when we say single coil and double coil, we’ll first take a look at the different parts of a pickup and see how they work together to produce a guitar signal.