What the F is F Spacing!

 If you didn’t know and many don’t, 6 string humbuckers come in 2 different pole spacing, the pickups
themselves are the same dimensions, just the poles are different distances apart.
This is due to the two main guitar companies in the early years (Gibson and Fender) having
different widths of their necks.  So to enable everyone to upgrade to better pickups DiMarzio made a Super Distortion
to fit both the Fenders and the narrower necked Gibsons.
(Before DiMarzio came along there were no replacement pickups!!)

The F revers to FENDER, this is the wider size pickup spacing measuring 51mm from the centers to center
of the outermost poles.  If you put an F spaced pickup into a Gibson it would work BUT it would not be optimal
as the poles picking up the string vibrations would not be in the optimum placement, they need
to be a bit closer together…… Yes you know it,it needs a standard spaced pickup.
It can sound complicated but it boils down to the distance between your outermost strings at the neck pickup
position and the bridge position. Almost EVERY 6 string guitar has followed either Gibson or Fender neck size as we have all become accustomed to that size now, anything else seems slightly odd now.

To check which spacing you need is easy.  Place a rule above the pickup you are looking to replace and measure the distance
between the fat E and the thin E string and now you know which you need.

DON’T measure your current pickup poles as if they were wrong to begin with you will just end up with Upgraded wrong spaced pickups.  Be sure to measure your string distances.

If you have an Guitar with a floating Floyd rose
type tremolo in almost all case you will need F spaced in both positions, BUT it’s always best to check.

F spaced measures 51mm
Standard spacing measures 48mm

f spacing

FROM DIMARZIO’S OWN SITE………..

How do I know which spacing to use?

F-spaced pickups measure 2.01″ (51 mm) center-to-center from the first polepiece to the sixth. Standard-spaced pickups
measure 1.90″ (48 mm). Although some players believe that F-spaced pickups are only for the bridge position of tremolo
bridge guitars, many guitars with fixed bridges (including post-1998 Gibson® and Epiphone Les Paul, SG and
semi-hollow guitars) should have F-spaced pickups in the bridge position. Most tremolo equipped guitars that have
a nut width of 1-11/16” (43mm) or more should also use an F-spaced pickup in the neck position. If you’re replacing a bridge-position
pickup and you’re not sure what your string-spacing is, it’s usually better to get an F-spaced model. It is not necessary for the strings
to pass exactly over the center of the polepieces for best performance, but it is wise to avoid a situation where the E strings are
sitting completely outside of the outer polepieces.