MUTE
Each crossover way provides of a mute switch in order to could cancel this way.
When this switch is pulsed, the corresponding way remains canceled, and lights a red
indicator associate to this switch. This switch is very useful to verify each one of the
ways for separating, cancelling all the ways less the one which is wanted to test.
The crossover muted all the ways when power is turned on, during a few seconds, in
order to protect the loudspeakers of turn on transitory and avoid unwanted noises. This one
could verify turning on the unit, and seeing that the mute indicators remains lit during a few
seconds.
PHASE SWITCH
This switch placed in the front panel of the crossover, allows to change the phase
of the way associated to it in 180º concerning their high way. The two more important
utilities of this phase switch are for the compensation of the phase change upon using
two different equipment, due to the wiring or the design of their different components,
and in second place in order to balance the phase change between two adjacent
ways, improving it of this manner the acoustical summation of the two ways. This last
utility takes place in conjunction with the phase adjustment, of the that will talk later on.
PHASE ADJUSTMENT BETWEEN WAYS
The phase adjustment between ways takes place through a rotatory potentiom-
eter placed at the front panel of the crossover. The configuration of this phase adjust-
ment is placed at the frequency card to obtain a precise control of 0 to 180º on the
relevant frequency. If used it in conjunction with the phase switch, will provide of a
phase adjustment of 0 to 360º.
The filters used in crossover unit (LINWITZ-RILEY), secures that in the relevant frequency
the two adjacent ways are in phase, however the differences between the loudspeakers in
the adjacent ways, makes that is very useful provide of a phase adjustment between ways.
The process recommended in order to carry out the adjustment phase in all the bands,
is leave the HIGH way of the crossover as reference, and go adjusting the phase succes-
sively, until reach at the LOW way.
Three simple methods in order to carry out the adjustment phase are:
1º) Using a spectrum analyzer and pink noise, until obtain the flattest frequency re-
sponse of the equipment.
2º) Applying a sinewave signal at the relevant frequency, and adjusting the phase
potentiometer of the way with lower frequency until the output signal achieves to the mini-
mum (cancellation) and then press the phase switch of the way with lower frequency.
3º) Listening the speaker system.
It is important point out that this adjustment is thought in order to regulate the phase
between the ways, and not as delay (except for the subwoofer output), in order to it is avail-
able an optional delay card, of the one which will talk later on.
In the subwoofer way the phase adjustment produces a adjustable delay until 6 ms
(200 cm) valid from 20 to 100 Hz (to high frequencies the delay begins to diminish). In order to
obtain the better phase alignment between the low and subwoofer ways is recommended
place the subwoofer cabinets in a more advanced position that the low one for so have a
margin of possible delay in the subwoofer way.
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