RANE AC 23B Active Crossover The Rane AC 23B Active
Crossover can be configured as stereo 2 or 3-way, or mono 4 or 5-way. It
features XLR connectors with active balanced inputs and outputs. It
also employs 4th-order Linkwitz-Riley filter alignments to minimize
phase difficulties in the critical crossover region. Simply put, a
Linkwitz-Riley alignment is two cascaded 2nd-order Butterworth filters
exhibiting identical phase characteristics on their Low-pass and
High-pass outputs. This characteristic guarantees in-phase outputs at
all frequencies. In-phase outputs are mandatory for proper acoustic
summing of common signals from adjacent drivers in the crossover region.
An added benefit of this topology is steep 24 dB per octave rolloff
slopes. A slope of this magnitude guarantees drivers designed to produce
a specific range of frequencies, and no more, will not be driven past
their limits, thereby minimizing distortion and driver fatigue.
To
further guarantee the transparent operation, adjustable time delay
circuits appear on the low and mid outputs of each channel to compensate
for any physical misalignment of the drivers. Time correction ensures
the mechanical phase alignment of adjacent drivers will be acoustically
correct, thus maintaining the integrity of the electrical phase
alignment of the crossover's filters. CD horn equalization is possible
with an internal modification. Time delay can also be internally
transplanted to the mid and high outputs if desired.