This device, in combination with a software oscilloscope or PC sound device, can measure the tonal response of electric guitar pickups. You can predict tone approximately, compare altogether different designs and evaluate the effects of different internal components such as magnets, compare different pickups of the same production run, detect defects like internal shorts that are not evident in a simple resistance measurement. With access to an online database, you can select pickups that are similar to ones that you already like, disprove specious claims about pickups, test new designs and so on.

The system works in the following way – a test signal is applied to a small coil through a resistor. This creates a magnetic test field that substitutes for a vibrating string. The coil is placed adjacent to the pickup, and a plot is created. There is a small problem – an alternating magnetic field generates a voltage signal that is the mathematical derivative of the field. This is predicted by Faraday’s Law. It is not part of the response of the pickup “as a filter”. So it is necessary to apply the inverse of differentiation, which is mathematical integration. The V6.0 device contains an “integrator” circuit to perform this function, as well as a highly sensitive preamplifier that prevents the circuit from itself affecting the pickup that it is connected to.