In the input, the signal crosses the two RFI filters and its electronically unbalanced. Later,
the signal go through two filters, the ultrasonic filter placed at 30 KHz and the subsonic one
placed at 30 Hz. In the INPUT CH2 the signal crosses the STEREO/MONO switch and it takes the
signal of this input when the switch is at position STEREO or of the INPUT CH1 when the switch is
at position MONO. The subwoofer way (SW) has a sum amplifier which converts the two input
signals in a single mono signal, because of this way is mono.
The next section is composite for the LEVEL amplifier, the phase change and the phase
adjustment, besides the MUTE switch. The last way (HIGH_R) doesn't have phase adjustment,
although it has phase change. This is because in the phase adjustment, this way leaves as
reference, because of what it is not necessary adjust its phase.
Later was the insert points of EQ and EQ/ DELAY, that interrupts the signal because of
what it is necessary introduce the jumpers (refer to the sections placing a equalizer or delay
card for more information).
The frequency cards share ways as you could observe in the diagram, always the low
pass filter belong to the previous way and the high pass filter to the hind one. All the ways
have two filters, except for the subwoofer way (SW) and the HIGH_R one, since in these two
ways are not necessary use more than one filter. Also one could observe that the only that
should make in order to overlap ways, are don't use the same relevant frequency for the high
pass filter that for the low pass one.
Lastly the signal is electronically balanced, and it arrives to the output connector. The
output connector is the place where in the turn on/off the relays momentarily begin to ground
the outputs (both terminal 2 and 3) in order to avoid turn on/off transitory.
In a box inside the diagram, is printed the limiter configuration, in which the voltage
controlled amplifier (VCA), limits the output tension (if it is active) when the signal goes over the
VCA threshold (TH). Also the level indicators take the input signal of this part of the circuit.
Beside the output connectors, it is the output configuration schematics depending on
the crossover configuration, as well as the bypass card position.
8. REPAIR GUIDE
In order to carry out a repair the crossover unit must be open, removing the eight
screws of their top cover.
NOTE: This type of operations, takes place with the unit open, because of what should be
carried out by qualified technical personal.
WARNING: Before opening the unit, disconnect it of the mains. It is important mark that al-
though the unit is turned off (with the power switch at position 0), if it continues connected to the
main there is different parts of the unit that are subjected to high tension.
CAUTION: Don't subject the divisor of frequency to humidity or rain, above all if it is open. If it
comes to produce, disconnect it of the mains and warns to qualified technical service.
Keep in mind that all the ways are symmetrical, because of what once certain the way
that is failing, you could exchange components, except for the circuits that are common to all
the ways as could be the power supply, or the delay turn on.
Before beginning to change anything in a unit, before carries out a meticulous visual
exam (burnt resistors, potenciometers with a broken trace, etc.). This exam many times gives
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