The magnetic acoustic guitar pickup is usually easy to spot when it is being used on a guitar; it is that thing in the soundhole.
Its construction is similar to that of the typical electric guitar pickup. In it’s simplest form: a magnet is wrapped with coils of wire to increase the size of the magnet’s field and placed close to the strings. Two leads from either end of the coil is connected to an amplifier. When the strings are strummed or plucked, the magnetic field is interrupted creating an electrical current or signal, which travels through the leads and then is amplified.
But many pickup designs are more complex. Some have pole pieces; individual magnets or screws magnetically charged for each string. Some have two pole pieces for each string to attenuate the initial attack of the string. Others have secondary hum canceling coils.
And, there’s more. A few have active circuitry, a battery powered pre-amp that allows the user to lower the volume without the loss of tone and/or some sort of EQ adjustment, most likely an over prevalent mid-range, and others have built-in microphones.
These pickups are resistant to feedback, so they work very well in full-band situations. And, of course, they allow the guitarist to move freely about the stage.
They typically clip into the soundhole or are held into place by gripping either side of the soundhole with foam or felt protecting the finish on the guitar. Many can be temporarily installed without loosening the strings, so the same pickup could easily be changed from one guitar to another.
With the use of a jack, or more commonly with an acoustic guitar, a combination endpin-output jack, the pickup can be more permanently installed.
Since they are merely sensing the strings interrupting their magnetic field (rather than amplifying the sound the way a microphone would) magnetic pickups initially sounded more electric than acoustic. But modern designs with the use of various types of magnets and coils now produce more pleasing results, if not accurate acoustic sounds. Several manufactures offer mic blending options with their higher-end magnetic pickups.
Some of the earliest electric-acoustic guitars were equipped with magnetic pickups, with the Gibson J-160E as used by John Lennon and George Harrison being one of the most notable. Some more modern examples of magnetic pickup being integrated into the design of the electric-acoustic guitar are being offered by Ibanez and Taylor.
Jake Kelly is a man on the constant search for enlightenment, if anyone finds it let him know so he can get some. For more of this hombre’s ramblings and the rest of L2P check out L2Pbandspace and L2Pnet.com.
Originally posted 2011-01-20 17:11:26.