Lexicon MPX 110 - Listening Test; Effects Listening Test; Shock Test; Audio Performance

Lexicon
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Edit Bypass Store Tap
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2. Press Store to execute the test.
3. The Level LEDs will light to indicate the test has been successfully completed.
LISTENING TEST
This test involves running audio through the MPX 110 with and without effects processing. This is helpful in
differentiating audio problems in the analog from the digital circuitry. The first part of this test is performed
without effects.
1. Connect two audio cables between connect the MPX 110 rear panel Left and Right Outputs and the
headphone amplifier Left and Right Inputs.
2. Attach the single end of a Y-connector into the output of the sine wave audio oscillator, and the Y end
into the MPX 110 Left and Right Inputs.
3. Set the headphone amplifier volume control to its lowest level.
4. Press and hold down the front panel Bypass button while powering on the MPX 110. Continue to hold
Bypass until the Power On Diagnostics are completed and the green Level LEDs light.
5. Turn VARIATION to 13, and verify that the Edit, Bypass and Tap LEDs are on, as shown below.
Edit Bypass Store Tap
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6. Press Store to execute the test.
7. Input a 1kHz sine wave at 0dBu to the MPX 110.
8. Turn the MPX 110 Input, Mix, Output, Effect Lvl/Bal, and Adjust knobs fully clockwise.
9. Put on headphones, then set the headphone amplifier volume to a comfortable listening level.
10. Individually adjust the MPX 110 Input and Output knobs over their entire range and verify that no pops,
clicks, or scratchiness is heard.
EFFECTS LISTENING TEST
1. Turn VARIATION to 14 and press Store to return to normal operating mode.
2. Verify that the processed audio has no audible pops, clicks, or distortion.
SHOCK TEST
1. Lift each corner of the MPX 110 off the bench 4 inches (4”) then drop. To prevent damaging the unit,
keep one corner of the unit touching the bench at all times.
2. Verify that no audio, or LED intermittence is caused by this action.
Audio Performance:
SETUP
Oscillator and Analyzer Default Settings
Unless otherwise noted the following settings are used for the audio performance tests:
Oscillator Analyzer
Waveform: Sine Filter: Off
Output: Unbal Bandwidth: 22Hz to 22kHz
–25Ω Inputs: 100κΩ
Float (except Gain=600W)
1. Connect the appropriate cable between the oscillator output and the MXP 100 Left input.
2. Connect the appropriate cable between the analyzer input and the MPX 110 Left output.
3. Turn the MPX 110 front panel Input and Output knobs fully clockwise.
4. Turn the MPX 110 front panel Mix knob fully counterclockwise.
5. Power cycle the MPX 110 while pressing and holding down the Bypass button. Wait until the Level
LEDs light, then release Bypass.