As promised earlier, here’s a picture of the magnetic field on the 5 string DeCola pickups, along with a plastic template showing (in black ink) a typical four string layout and where they’d fall in relationship to the magnetic fields of each pole.
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From the looks of it, the four string bass strings will line up perfectly between each pole position on all four strings. So you should get a fairly even response from each string.
By comparison, here’s a picture of Gibsons Flagship bass, the Memphis LP Gold Top, which clearly has 6 string split coil guitar pickups in it, some strings are directly over the hot spots and some are between the poles - it sounds fine.
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