M-AUDIO Duo USB - Manual (Page 11)

speakers, or a headphone amplifier, or to the inputs of a mixing console. Again,
check your device’s documentation for information on its operating line level,
and see the section, “Using the Input and Output Level Switches.” The Duo’s
S/PDIF Out can be connected to any S/PDIF capable device, such as a DAT or
MiniDisc with coaxial S/PDIF inputs.
The diagrams below illustrate two scenarios, intended as examples of how the
Duo might be used. Typical Setup #1 shows the Duo with a microphone plugged
into the Mic input on Channel 1, and an electric guitar with direct box plugged
into the Mic input on Channel 2. The main outputs (Line Out) of the Duo are
plugged into a monitoring system, with the S/PDIF Out connected to the S/PDIF
input of a DAT recorder (as you would if you were mixing down). Typical Setup
#2 shows a CD player plugged into the Line Input on Channels 1&2, with
Outputs 1/2 plugged into a monitoring system.
Using the Input and Output Level Switches
Using the front panel Input Level and/or the back panel Output Level switches,
you may change the operating line level for each of the Duo’s stereo pair Line
Level Inputs or Outputs. In the “out” position, the Duo is set to a +4dBu line
level. Pressing the input level switch and locking it to the “in” position changes
the operating line level to a -10dBV setting.
You can, in fact, have the input set to one line level and the output set to another,
depending on your needs. This will depend on the operating line level of the
device that is attached to that particular input or output. Your goal is to match the
Duo’s input or output line level to the line level of your source or target device.
Generally speaking, a device that runs at a -10dB line level will have outputs or
inputs that are single conductor with a ground, such as RCA jacks, or 1/4”
tip-sleeve phone jacks. Devices that run at a +4dB line level will have outputs or
inputs that are two conductor with a ground, such as XLR or 1/4” tip-ring-sleeve
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