The programmable digital crossover shall consist of four inputs
and eight outputs with the ability to assign any output to any
input. Each input channel shall include: a delay stage with a
maximum delay of 682.5ms; a gain stage capable of +12dB
boost and -40dB cut; six filter stages configurable to be a para-
metric filter with a frequency range of 19.7Hz to 21.9KHz, 1/24th
octave step and a +15dB boost, -40dB cut, or a 6 or 12dB/
octave high or low shelf filter. Each output channel shall include:
a routing stage allowing the user to assign the output to any or
a combination of input(s); a high pass/ low pass crossover filter
stage with selectable slopes of 12, 18, 24 and 48dB per octave
using Linkwitz-Riley, Bessel or Butterworth filter configurations;
four filter stages configurable to be a parametric filter with a
frequency range of 19.7Hz to 21.9KHz, 1/24th octave step and
a +15dB boost, -40dB cut, or a 6 or 12dB/octave high or low
shelf filter; a delay stage with a maximum delay of 21.33ms; a
gain stage capable of +12dB boost and -40dB cut and the abil-
ity to invert the phase; a full function compressor/limiter with
a threshold range of -20dBu to +20dBu. Each input and output
shall have individual mute capability. The programmable digi-
tal crossover shall have a maximum in/out level of +20dBu.
Frequency response shall be ±.25dB 20Hz to 20kHz. Dynamic
Range shall be greater than 110dB (20-20KHz, unweighted)
and SMPTE intermodulation distortion or THD shall be less than
0.01% at 1KHz, +20dBu. Input impedance shall be 18K ohms
active balanced. Output impedance shall be acive balanced, 100
ohms. Inputs and outputs shall be balanced type on XLR con-
nectors. A 2 X 20 backlit LCD display will show all parameter,
function and utility information. LED indicators shall show signal
level, clip, limit threshold and mute conditions. Full program-
ming and control of the unit shall be from the front panel or via
the front panel accessable RS-232 serial port using Ashly Protea
System Software, or via MIDI. There shall be 30 factory presets
that may be overwritten by the user and stored. There shall also
be a four level security lockout feature. The programmable digital
crossover shall weigh 10 lbs net and mount in a standard 19”
rack using 1 space (1.75” high). The power requirement shall
be 80-260VAC, 50-60Hz, 30W. The unit shall be an Ashly Audio
Protea System II 4.24C Digital Crossover/System Processor.
• Four Inputs - Eight Outputs
• Outputs Assignable to Any Input
• Crossover, EQ, Delay and Limiter
• Linkwitz-Riley, Bessel and
• 12, 18, 24 and 48dB/Octave Slopes
• Parametric EQ: Full Bandwidth,
• Intuitive User Interface
• Programmable by Front Panel, PC or
• Individual Input and Output
• Balanced Inputs and Outputs
• Password Protected System Security
Technical Notes & Specifications
Protea System II 4.24C Digital Crossover/System Processor
Architects Speci cations
