A common pickup for an electric guitar consists of a coil of wire around a small permanent magnet, as described in Figure 25.5. Why will this type of pickup fail with nylon strings?
Guitar pickups are tiny coils with magnets inside them. The magnets magnetize the steel strings. When the strings vibrate, voltage is induced in the coils and boosted by an amplifier, and sound is produced by a speaker.
This type of pickup, known as a magnetic pickup, relies on the magnetic properties of metal strings to generate an electrical signal. Nylon strings, on the other hand, do not have magnetic properties and therefore do not interact with the pickup's magnetic field. As a result, the pickup fails to detect the vibrations of the nylon strings, leading to no or very weak electrical signals being produced.
To understand this better, let's break down the working principle of a magnetic pickup. The coil of wire in the pickup is wound around a permanent magnet. When metal strings, such as steel or nickel, vibrate near the pickup, they disturb the magnetic field produced by the magnet. This disturbance induces a small electric current in the coil of wire, which is then amplified and processed to produce the sound of the guitar.
In the case of nylon strings, they are usually made of materials like nylon or gut, which are non-magnetic. Since they lack magnetic properties, they do not disturb the magnetic field created by the pickup's magnet. As a result, the coil of wire does not experience any changes in the magnetic field and, consequently, no electrical signal is generated.
To overcome this limitation, if you want to use a magnetic pickup with nylon strings, you would need to replace the nylon strings with metal strings that have magnetic properties.