Speaker wiring will inherently "drop" some voltage, depending on the wire's resistance and the current being supplied to the speakers.  This calculator helps determine the minimum wire gauge necessary to deliver DC power to speakers.  The voltage drop calculated for all the speakers on a wire run determines if the wire gauge is acceptable.

This calculator assumes the power supply to be at one end of the wire run, with speakers daisy-chained on the wire.  Note that by using properly placed remote power supplies, it is always possible to use standard 22 or 24 AWG twisted pair telephone wire for self-amplified speaker connections.

To use this calculator, select the Valcom speaker from the list in the Model column.  The Valcom Power Units (VPU) required for each speaker will be determined from the model selected.  For the first Distance, enter the length (in feet) from the Power Supply to the first speaker.  For each additional speaker added, enter just the distance from the previous speaker.

Acceptable gauges will be noted with "Yes" in the Supported row.