JBL Professional MPC-XU - Manual (Page 6)

6
Ultrasonic Filter
Applications: An ultrasonic filter is useful for minimizing RF interference, oscillations,
leakage or aliasing from digital devices, or other signals that are too high in pitch to hear but
may wreak havoc in an amplifier system.
Typical ultrasonic filters are set at 16 kHz or 20 kHz.
Program settings:
1 Set Jx01 to enable the low-pass filter by placing jumper across pins 2 and 3.
2 Set Jx02 to disable the high-pass filter (if not using) by placing jumper across pins 1 and 2.
3 No jumper on Jx03.
4 Insert proper resistor network in RNx02 socket.
Bandpass Filter
Applications: A bandpass filter is useful if the speaker system has a limited bandwidth.
Program settings:
1 Set Jx01 to enable the low-pass filter by placing jumper across pins 2 and 3.
2 Set Jx02 to enable the high-pass filter by placing jumper across pins 2 and 3.
3 No jumper on Jx03.
4 Insert proper resistor network corresponding to the lower limit of the desired passband in
RNx04 socket.
5 Insert proper resistor network corresponding to the upper limit of the desired passband in
RNx02 socket.
CD Horn Equalization Filter
Applications: A constant directivity horn requires a 6 dB per octave boost at high frequen-
cies to provide a flat frequency response. On the MPC-XU you must use the CD horn
equalization in conjunction with the high-pass filter.
Program settings:
1 Set Jx01 to bypass the low-pass filter (if not using) by placing jumper across pins 1 and 2.
2 Set Jx02 to enable the high-pass filter by placing jumper across pins 2 and 3.
3 Set Jx03 to select the EQ curve you desire: across pins 1 and 2 to +6 dB at 20 kHz, or
across pins 2 and 3 for +10 dB at 20 kHz.
Subsonic Filter with CD Horn EQ
Applications: This would be suitable only if the loudspeaker system uses a passive crossover.
Program settings: Use settings 1, 2 and 4 from the subsonic filter instructions and setting 3
from the CD horn equalization filter instructions above.
Subsonic and Ultrasonic Filter
Program settings: Use settings 2, 3 and 4 from the subsonic filter instructions along with 2
and 3 from the ultrasonic filter instructions above.
High-pass
freq. (set
by RNx04
and Sx02) Low-pass
freq. (set
by RNx02
and Sx01)