11
MASTER SECTION
26 - 2 TRK LEVEL
The 2TK LEVEL control knob is used to set the volume
level of the source connected to the 2-track input. If you
want to mix in a CD, tape or MP3 player with your input
channels connected to the 2TK inputs, use the 2TK LEVEL
to adjust the level.
Auxiliary Returns
The MDR1248 and MDR1688 have two stereo auxiliary
returns, which can be accessed via the two pairs of 1/4-
inch phone jacks located on the master section jack field.
The auxiliary returns can be used to connect any stereo
line level signal, but they are primarily used to connect
the output of external effects processors.
Controls and Functions
27 - AUX RET 1 control knob
This adjusts the amount of signal that is sent from the AUX
1 RET jacks to the MAIN bus.
28 - AUX RET 2 control knob
The AUX RETURN 2 adjusts the level of the signal present
at the AUX 2 RET jacks. This signal is summed, or mixed in
to the main L/R MIX bus.
29 - AUX 2 RETURN TO AUX 1 switch
This routes the signal that is present on the AUX 2 RETURN
jacks to AUX 1 so that the effects can be heard in the
monitor mix.
30 - AUX 1 SEND control knob
The master AUX SEND control is used to send the effect
mix bus to an external effect device connected to the AUX
SEND 2 jack.
31 - AUX 2 SEND control knob
The master EFX SEND control is used to send the effect
mix bus to an external effect device connected to the AUX
SEND 2 jack.
32 - ALT 3/4 Level control knob
Use this control knob to set the level of the mix created
from the channels assigned to the 3/4 bus. The ALT 3/4
level control will control the level of the signal being
sent to the 3/4 Output jacks. When the Master ALT 3/4
switch(43) is switched in, the ALT 3/4 level control will con-
trol the level of the ALT 3/4 mix that is heard in the Main
Left and Right mix. Remember, the ALT 3/4 TO MIX switch
must be set to the on or down position in order to hear
the 3/4 mix in the main Left and Right mix.
33 - SOLO LED
The LED will illuminate when any one or more channel's
SOLO switch is engaged, indicating that there is a channel
in solo.
34 - LEVEL SET LED
When a channel's SOLO switch is pressed, the LEVEL SET
LED will illuminate and flash indicting that the channels
input level is now being measured by the main VU meter.
35 - MODE (AFL/PFL) switch
You can change the mode of the SOLO bus from Pre fader
listen to After, or Post fader listen using the MODE switch.
When the switch is pressed in, the SOLO mode is set to
AFL (After Fader Listen), so the channels signal is sent after
or post fader. When the switch is pressed out, the SOLO
mode is set to PFL (Pre Fader Listen), so the channels sig-
nal is sent before or pre fader.
36 - PROGRAM control knob
The MDR1248 and MDR1688 feature an internal 24-bit
DSP with 256 presets. The presets are organized in sixteen
Program banks, each with sixteen variations. The Program
control knob used to select one of the sixteen DSP effect
programs.
37 - VARIATION control knob
The MDR1248 and MDR1688 feature an internal 24-bit
