In certain situations signal needs to be manipulated. It is done in crossovers, to take care that each driver gets the frequencies it performs best. Also some drivers are non-lineair. Fast speakers for example always have higher sound pressure at higher frequencies, if a speaker is lineair it is in fact too slow to produce high frequency in a normal matter. Speakers can be adjusted in passive crossovers between the amplifier and speakers, but this means adding more parts in the high power signal, almost impossible to do totally right. You also need high values, which are hard to find in very good quality. Also in some systems the signal output is too high, typically a volume control cannot be turned up high than the 8 or 9 o'clock position for full power. It is beter for the S/N to have higher volume control positions.

It is possible to make the crossover active, to correct the speakers non-lineairity and to damp the signal. All have great advantages. Active crossovers take care amplifiers only have to do their own area, damping factor of the amplifiers is utilized fully and filters can be made much better, and for example as cascade first order, instead of higher order systems. Corrections also can be made exactly inverse of the speakers non-lineairity. Damping the signal in front of the power amplifiers means a much better signal to noise ration in the whole system, and more flexibility at the volume control.

Pink Faun develops so called passive active modules which take care of all the above. The module mount directly at the input of the power amplifiers, making it in fact and active system with the power amplifier as buffer. The system will play more music, it even is possible to make a complete active system with out modifying your equipment or adding active crossovers. In each situation a module can be fixed.