Lexicon
MPX 1 User Guide
1-4
The MPX 1, with both analog and digital input and output connections, requires
some attention to proper setting of signal level.
Analog inputs are first gain-conditioned by the rear panel input level switch, and
then by the front panel Input knob. Proper setting of both the switch and knob
are important for best performance of the A/D converter.
Analog and digital sources are selected in System mode on the Input/Clck
screen of the Audio menu. The selections are: Analog/Int, Analog/Ext and
Dig/Ext.
Proper setting of Input level is dependent on:
•
Proper signal level into the analog front end to avoid signals causing overload
at the Digital Signal Processing (DSP) input (rear panel Input button)
•
Proper adjustment of the signal level into the analog-to-digital converter to
optimize noise and avoid overload (front panel Input knob)
•
Proper setting of signal level within the digital signal processor to optimize
noise (Lvl parameter in each effect block)
Setting Audio Levels
Mono Applications: Using the MPX 1 Outputs with Mono Return
Virtually all of the MPX 1 programs generate stereo or dual output signals, even
when driven by a mono source. For the best sonic results, the MPX 1 outputs
should be connected in stereo. If you are using the MPX 1 in a mono system with
only a single input, use a simple 2 x 1 mixer or a Y-connector to combine both
outputs.
NOTE
Individual programs can be optimized for mono input by simply inserting a mono
effect, such as Volume (M), into the last block of the routing map. See Chapter
3: Editing for more information on routing. See Chapter 7: The Effects and
Parameters for more information on individual effects.
Be careful to keep input and output to all channels wired consistently. Out-
of-phase wiring can produce audible effects.
Footswitch/Footpedal
One 1/4 inch T/R/S phone jack is provided for 3 momentary footswitches.
Another 1/4 inch T/R/S phone jack is provided for a footpedal (minimum 10k to
maximum 100k impedance). Normally open or normally closed momentary
switches are suitable. At power on, the MPX 1 assumes the switch is off. Use
shielded, twisted-pair cable with shield connected to sleeve. See diagram on
previous page. See also Chapter 5: System Controls for information on pedal
calibration.
MIDI
5-pin DIN connectors are provided for MIDI THRU and OUT. A 7-pin DIN
connector is provided for MIDI IN or a powered remote. Use standard MIDI cable
assemblies, available from your local dealer.
