ABSTRACT
When selecting the power amplifiers that are to work with active crossovers, the first consideration is how much power is required in each band. Earlier in this chapter we looked at the amplitude/frequency distribution of musical signals, and found that while the LF and MID bands may have roughly the same amplitude, the HF band may be between 5 and 20 dB lower, depending on where the MID/HF crossover frequency is set. Converting this into Watts (with their square-law relationship with Volts) tells us that if the LF and MID bands require 100W amplifiers, that for the HF channel need be capable of no more than 31 Watts in the worst case. There is some useful information on amplifier power requirements in Penkov [4].
