Price is $300 obo .
XM9 Electronic Crossover Network
Steep 24 dB/octave slope.
Outputs are always in phase.
Crossover frequency choice 10 - 20000 Hz.
Subwoofer summing option.
Gold plated RCA connectors.
No transients during turn-on or turn-off.
Fourth-order constant-voltage design.
Low-noise circuit design.
Available 2-way stereo and 2-way 3-channel.
The XM9L Electronic Crossover Network is a fourth- order constant-voltage crossover design that provides both low-pass and high-pass outputs. The slope of each output is 24 dB/octave and, because of the fourth-order design, the high-pass and low-pass outputs of the crossover are always in phase with each other. The crossover network is implemented as a fourth-order state-variable filter. This filter provides both the high-pass and the low-pass function simultaneously, guaranteeing a perfect match of the high-pass and low-pass responses.
The XM9L is used between the audio preamplifier and power amplifiers. The two outputs of the crossover network (one carrying the high frequencies and the other carrying the low frequencies) feed the inputs of two power amplifiers, one for tweeters, one for woofers. This is a bi-amplified system (two amplifiers per audio channel). When used with a common subwoofer a sum switch on the front panel allows summing of the low-pass channels. The level of each output is set with a 12 position attenuator on the front panel. The attenuators have 1 dB steps.
The crossover frequency of XM9L Electronic Crossover Network can easily be set by replacing the set of 2 frequency modules, located inside the cabinet. The damping control sets the response at the crossover point. In the center position the response is flat. Set fully counterclockwise there is a 4 dB dip at the crossover point and set fully clockwise there is a 5 dB peak. This extra control enables perfect matching of the speakers at the crossover point. When power is turned on or off, a relay grounds the outputs of the XM9 (for about a second after turn-on; immediately upon turn-off) to eliminate potentially damaging transient signals at the outputs. The crossover uses only high grade components: 1% metal- film resistors, 1% polypropylene-film capacitors for the filter capacitors, and four dual FET-input operational amplifiers. Gold-plated connectors for input, output, and power make installation easy.
Available options include 24 position stepped attenuators instead of the standard 12 position stepped attenuatorsfor level control. These stepped attenuators are calibrated in 0.5 dB steps and allow very accurate setting of the levels for each output.
Balanced inputs/outputs are also available as an option.