The smaller inset diagram illustrates how string movement is limited by excessive magnetic force. This force shortens the string's duration of motion and limits the loop width, causing loss of sustain and output power. This allows the guitar string to span a center zone of zero force, which imposes no resistance to string motion. The black areas in Diagram B show that the zone with the greatest magnetic force is in the rim of the pole piece. Notice how the force is shifted to the side, away from the string's path of motion.
Outward arrows indicate the absence of resistant force.
The smaller, inset diagram illustrates the string's freedom to develop its optimum loop, lengthening the duration of its motion for greatly increased sustain and output power. Bonded Construction Produces Accurate Tonality. A pickup responds to both external and internal sources of motion and vibration, which can be problematic at high volume levels. Therefore, no single component can vibrate to cause feedback or microphonics. ZP tubular pole pieces are placed in close proximity to the coil's core windings for increased pickup response.