500 Words with Adam P Hunt- Pick up Magnets
Adam P Hunt is a freelance writer who has previously written for The Library Journal and Premier Guitar Magazine. We are so happy to have him join us here at Guitar Radio Show.com.
500 Words From Adam P Hunt Magnets
The use of magnets is an old one and extends at least as far back as 600 BCE. Alnico magnets, the ones that we as musicians have come to know and love, however, are a startling recent development and only dates back to 1935.
Interestingly enough of Einstein’s work on the Unified Field Theory (an attempt to unify the conflicts between radiation, gravity and electro magnetism) dates from 1915 to 1933 after he wrote the On the Electrodynamics of Moving Bodies in 1905.
For centuries alchemists, amateurs, tinkerers, scientists and crackpots have sought not only to understand how magnets work but equally importantly how to make them more stable and permanent.
1921 saw the development of one of the first permanent magnets, the cobalt chrome steel magnet. The cobalt chrome steel magnet was quickly soon followed by the alnico and cunife magnets in 1935, the platinum cobalt magnet in 1936, ferrite (ceramic) magnets in 1951, samarium cobalt magnets in 1969, and rare earth magnets developed throughout the 1970’s and ‘80s.
Permanent magnets allowed stable, long lasting, powerful magnetic fields. According to The Magnetic Materials Group of SPS Technologies paper titled “Understanding and Using Permanent Magnets”;
“A permanent magnet is a material that when inserted into a strong magnetic field will not only begin to exhibit a magnetic field of it’s own, but also continue to exhibit a magnetic field once removed from the original field. This field would allow the magnet to exert force (ability to attract or repel) on other magnetic materials. The exhibited magnetic field would then be continuous without weakening provided the material is not subjected to a change in environment (temperature, demagnetizing field, etc.). The ability to continue exhibiting a field while withstanding different environments helps to define the capabilities and types of applications in which a magnet can be successfully used.“
These properties are extremely desirable where small magnets are needed especially in certain types of motors and watches, and especially for microphones, speakers, and guitar pickups.
Brian Robinson wrote a piece for the Scotty Moore website http://www.scottymoore.net/ on the rise of the now fabled alnico V magnet pickups;
“Though the pickups had a specific designation at Gibson, they are referred to by collectors as “alnico V” pickups because they incorporated alnico V magnets. Use of an alnico V magnet isn’t particularly unique (Gibson has used the same magnet on several pickups) but that name has always stuck with that pickup. The pickup was designed by Seth Lover, the man who invented the humbucker. Gibson had been using the P90 pickup exclusively on all electric guitars for several years. Gibson asked Lover, who worked for Gibson in its R&D and electronics department, to come up with a more powerful pickup that more closely resembled the D’Armond single coil pickup that was popular at that time (D’Armonds were most notably used on the Gretsch duo jet line and other Gretsch electrics)”.