MDB S
eries Dir
ect Bo
xes
8
MDB Series Direct Boxes
MDB Series DIrect Boxes: Front Panel Features
1. Input Jacks
The signal output from an instrument (active
or passive) may be connected to this unbalanced
line-level 1/4” input by means of a shielded instrument
cable. This includes guitar, bass, keyboard, media
players and more.
They are wired as follows, according to standards
specified by the AES (Audio Engineering Society):
Unbalanced 1/4" Input Connector
Tip – Positive (+ or hot)
Sleeve – Shield (ground)
NEVER connect the output of an amplifier
directly to an MDB Series Direct Box’s input
jack. This could damage the input circuitry
and we wouldn’t want that now, would we?
2. Thru Jacks
The Thru jack may be connected to the input
of an instrument amplifier or instrument-level
parallel effects device (such as an FX device chain,
processors, or tuner). This output is unaffected
by the MDB Series Direct Box’s circuitry.
SLEEVE
TIP
TIP
SLEEVE
TIP
SLEEVE
Unbalanced 1/4" Connectors
PAD
PAD
0 dB
-15 dB
0 dB
-15 dB
THRU
INPUT
LEFT
RIGHT
MDB-2P Front Panel
1
2
3
3
3. Pad Switch
Put this switch in the down position to reduce
the input signal by 15 dB and compensate for higher
output sources. This attenuation is suited for use with
instruments that have active electronics or high-output
pickups.
It is a 20 dB pad on the MDB-1A and the
switch is reversed from the MDB-1P and
MDB-2P; –20 dB in the up position, 0 dB
when the switch is down.
4. Merge Switch [MDB-1A]
When the Merge switch is in the OFF position
(switch up), the Thru jack works as normal
(see #2 description, bottom-left).
When the Merge switch is in the ON position (switch
down), the Thru jack works as an additional input.
It will be summed with the main input to create a mono
output source. This is a perfect solution for stereo
sources like keyboards and media players.
Additionally, the associated LED will illuminate
when merge is on.
MBS On / Off Switches
The rare and highly sought after MBS–FNMA and
MBS–GNMA Direct Boxes come with switches to turn
off your mind, body and soul when any (or all) of them
need it. When will you know? Oh, you’ll know. When it’s
there, simply flip the switch to off and when you’re
feeling good again, go ahead and flip the switch back
to the on (up) position.
INPUT
MERGE
PAD
THRU
ON
OFF
0 dB
-20 dB
POWER
MDB-1A Front Panel
1
2
3
4
INPUT
PAD
0 dB
-15 dB
THRU
MIND
ON
OFF
BODY
ON
OFF
SOUL
ON
OFF
MBS-FNMA & GNMA
INPUT
PAD
0 dB
-15 dB
THRU
MDB-1P Front Panel
1
2
3