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What's the output, in ohms?
D.C. resistance readings are an easy way to check a pickup's connections, using an ohmeter. The measurement refers to the 'resistance' of the pickup to the flow of D.C. voltage supplied by the ohmeter. But, this measurement has little relationship to the pickups actual output. Remember that during this measurement the output is actually Zero, regardless of the resistance reading. The resistance reading is affected mostly by the diameter of the coil wire and the number of turns. While each of these contribute to the tone and output of a pickup, there are other important factors that affect the output at least as much. The music you play is converted to A.C. voltage by the pickup. Resistance to A.C. voltage is Impedance and this can have a significant effect on the tone. Some of the other elements that affect the tone are the size, strength, and shape of the magnetic field, and how the coil is wound and positioned in relation to the magnets and strings. None of these factors can be measured on an ohmeter. Consider that a Tele neck pickup and a Gibson P-90 have a very similar D.C. resistance (within 15%), but radically different output levels, for the very reasons cited above. Some pickups simply produce more output without necessarily measuring more resistance. Also keep in mind that identical coils with exactly the same number of turns, often show different D.C. resistance readings, and so 'matching' coils by ohmeter readings is largely guesswork. |