Owner
’s Manual
9
Owner’s Manual
5. XLR Output Jacks
These XLR connectors provide a balanced line-level
signal that is designed to connect to the inputs of a
mixer or audio interface.
They are wired as follows, according to standards
specified by the AES (Audio Engineering Society):
Balanced XLR Output Connector
Pin 1 – Shield (ground)
Pin 2 – Positive (+ or hot)
Pin 3 – Negative (– or cold)
6. Ground Lift Switch
The ground lift separates the chassis ground from
the signal ground at the balanced output jacks. The
default position is ground. You may attempt to remedy
system ground loop hum by moving the switch to lift.
Balanced XLR Connectors
2
1
SHIELD
COLD
HOT
3
SHIELD
COLD
HOT
3
2
1
RIGHT OUTPUT
LEFT OUTPUT
GROUND
LIFT
MDB-2P Rear Panel
5
5
6
7. Low Cut Switch [MDB-1A]
When on, the low-cut switch (often referred to as a
high-pass filter) cuts bass frequencies below 120 Hz.
We recommend that you use low-cut on every
microphone application except kick drum, bass guitar,
or bassy synth patches. These aside, there isn’t much
down there that you want to hear, and filtering it
out makes the low stuff you do want much more crisp
and tasty. Not only that, but low-cut can help reduce
the possibility of feedback in live situations, and it
helps to conserve amplifier power.
Another way to consider low-cut’s function
is that it actually adds flexibility during live
performances. With the addition of low-cut,
you can safely use low equalization on vocals. Many
times, bass shelving EQ can really benefit voices.
Trouble is, adding low EQ also boosts stage rumble,
mic handling clunks and breath pops from way-down
low. Applying low-cut removes all those problems,
so you can add low EQ without blowing the woofers.
8. Polarity Switch [MDB-1A]
When this switch is up, it reverses the polarity of the
signal by 180˚.
There is no right or wrong setting for this switch.
Listen to the overall blend with the rest of the system
and select the switch position that gives you the best
sound for your audience. In fact, your system may vary
when positioned differently and in alternate venues.
Don’t be afraid to experiment with the position of the
polarity switch.
OUTPUT
POLARITY LOW CUT
GROUND
LIFT
OFF
ON
180°
0°
MDB-1A Rear Panel
5
6
7
8
MDB Series DIrect Boxes: Rear Panel Features
OUTPUT
GROUND
LIFT
MDB-1P Rear Panel
5
6
