The magnet types checked were both polished and rough cast: Various new Alnico II pickup magnets measured at gauss levels ranging from 22 to a high of 35, with most in the 25 to 30 gauss range. New Alnico V magnets ranged from 22 to a high of 36, with most in the 30 to 35 gauss range. The type and strength of magnet in a pickup can have about as much impact on tone as winding resistance. All other factors being equal, a weaker magnet effects tone by lowering both output and resonant peak perceived as a less prominent high-midrange and treble response.
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What You Need to Know About Gibson Serial Numbers
But, with more than 75 years of shipping records in the Gibson books, and dozens of variations on numerical schemes used over the years, serial numbers sometimes do little to shed light on the origin of a mysterious Gibson. With vintage Gibsons selling at auction for as much as half a million dollars, Davidson will sometimes roll up his sleeves and poke around in the ledgers, but only as time allows. The earliest volumes contain hundreds of yellowed pages covered front and back with rows of handwritten numbers. It can take Davidson several hours to locate a specific serial number, if he can find it at all. Even then, there may be four other guitars—of all different models—with the same number sequence. Serial numbers can pull up multiple guitars from multiple years.
Then from to note overlap the next Gibson humbucker is known as the "T bucker" or "T top". They are called this because of a "T" that is part of the molding on the front of the two pickup bobbins. These also had the decal with "Patent No 2,," still the patent number of Les Paul's trapeze tailpiece. The only way to see the "T" is to remove the pickup cover. A small change in late patent pickups was white PVC bobbin wires instead of black black was used on pre humbuckers.
Great guitar--one that I have always wanted. However I discovered that Gibson may have been somewhat "loose" at that time after ? In mine there were two apparently standard humbuckers with metal-stamped "Pat. Same with some of the two-pickup Gibson guitars like the Les Paul models. And yet the Gibson catalogs of these years describe all as having '59 Les Paul Reissue pickups.