Mps1000, Controls and functions – JBL MARINE MPS1000 User Manual

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CONTROLS AND FUNCTIONS

The MPS1000 has several controls and indicators that simplify sonic
integration with the rest of the speakers on your boat. To gain access
to the controls, you must remove the cover and the water-tight
rubber plug underneath. To remove the cover, remove the two small
Phillips-head screws and pull the cover away, according to the arrow
in Figure 4. To reinstall the cover, follow the arrows in Figure 6 and
replace the two screws.

Figure 4. Removing cover

Figure 5. Rubber plug

NOTE: Be sure to replace the rubber plug after making adjustments.

Figure 6. Reinstalling cover

Figure 7. MPS1000 controls on the front panel

Power LED: This indicator will glow blue when the MPS1000 is
operational.

Gain Control: Use this control to adjust the volume (loudness) of
the MPS1000, compared to the loudness of the other speakers in
your boat.

Crossover: Use this control to adjust the amount of high-frequency
information in the MPS1000’s output. A lower value means less
high-frequency signal will be present in the MPS1000’s output.

Bass Boost: Use this control to correct any perceived peak or dip
in the bass response. This control provides boost or cut at 50Hz.
Set the control to any value between 0dB and +7dB, according to
your preference.

Phase Control: Use this switch to reverse the phase of the MPS1000’s
output, with respect to its input. Choose the position (0° or 180°) that
sounds best. See “Tuning the MPS1000.”

TUNING THE MPS1000
1. Make sure the head unit is off and its volume control is set to

minimum.

2. On the MPS1000’s front panel, set the Gain control to the midpoint

position.

3. Set the Crossover control to its maximum position (clockwise).
4. Set the Bass Boost control to the minimum position

(counterclockwise).

5. Set Phase to 0.°
6. Turn on the head unit and play a favorite music track that has

substantial bass. Set the head unit’s volume control to 75% of the
total output (approximately 3 o’clock on rotary controls).

7. Listen to your system, making a mental note of the amount of upper

bass being reproduced.

8. Switch the Phase control to 180° and listen again for upper bass

content. There may be more upper bass, less upper bass, or no
change at all. The position that provides the most upper bass is
correct.

9. Adjust the Crossover control clockwise or counterclockwise

until you hear only low-frequency information in the output of the
MPS1000. For example, you should NOT hear any vocals coming
from the MPS1000 when seated in the normal listening position.

10. Adjust the Bass Boost control clockwise to suit your preference.

NOTE: In most cases, the steps above will provide satisfactory tuning.
However, the actual process may require several readjustments of
each control, since the settings will interact with each other. If
necessary, consult your authorized JBL car or marine audio dealer
for help in tuning your system.

NOTE: Depending on the MPS1000’s orientation and location in your
boat, reversing the phase may (or may not) increase or decrease the
amount of upper bass being reproduced.

Phase

max

120

min

Boost

Crossover

Gain

0°

180°

MPS1000