G&L tech resources: Pickups


The first Magnetic Field Design (MFD), and hence the first implementation of US Pat. 4,220,069, appeared on the L-1000 bass in 1980. Later that year, the L-2000 and L-2000E were added with a pair of MFD buckers. The pole piece screws saw a couple of iterations: from socket head cap screw, adjustable with a large (⅛“) Allen wrench (e.g. this 1980 L-1000), to cheese head slotted machine screws between 1981-1982 (e.g this 1981 L-2000E), and finally back to a socket head cap screw for a smaller (⁵⁄₆₄”) Allen wrench (e.g. this 1983 L-1000F). The use of slotted pole pieces is interesting in the context of US Pat. 4,686,881 Leo filed for on September 30, 1985. It claims that the orientation of the slots of the (oversized) cheese head machine screws makes a big difference in sound. It can make the instrument more percussive when oriented perpendicular to the string and traditional sounding when parallel, allegedly due to the direction of the magnetic field lines around the heads. However, by the date of filing, slotted pole pieces were no longer used on the bass MFD humbucker. Early versions of this pickup do not show the patent number on the covers which was added around the end of 1981. As seen below, note that both coils are in completely separate compartments within the pickup cover. Check out the wiring harness to see where the white-black pair and green-yellow pair end up. As was common, on models with all gold hardware, even the pole pieces are plated as seen on this ASAT Bass Commemorative Edition. On the Climax Bass, which evolved later into the L-1500, the single pickup is placed closer to the bridge, but just a tad further away as the bridge pickup on either L-2000 or ASAT Bass. One had to wait until the mid-1990s until a 5-pole version was added as employed on this L-2500. When visiting G&L’s website or its store, this pickup is referred to as the L-series pickup. The newer M-series humbucker, introduced in 2011, is voiced to optimize the specially designed BEQ3 (Rev. 1.0) preamp for that line of basses.


Bass: MFD humbucker