The AC 24 stereo 4-way Crossover combines conventional analog controls and DSP signal processing. The AC 24 is ideal for those who want the features and accuracy of DSP, but prefer not to use a PC for control. One knob = one function -- no confusion. This approach allows a full-featured, high performance product that doesn't break the bank. The AC 24 is a truly affordable crossover that features the very best technology, with exactly the right features.