www.rolls.com
www.rolls.com
3
8
PAN CONTROL
The Pan control routes an input channel signal anywhere between the Left and Right
outputs. The MX422 uses constant loudness pan controls, meaning that the signal is 3
dB louder at the full right or full left position relative to the center position. Usually, the
channel is either panned full left, full right, or center.
The pan potentiometer has a detent in the center position for easy location, and it is
calibrated for a maximum diff erence of +/- 0.1 dB between the left and right output in
this position.
LIMITER
The MX422 Limiter acts as a
”
safety
”
limiter. During normal operation, with a properly
set gain structure, the threshold of the limiter will not be reached. If extremely high in-
put signal levels exist, such as in high SPL environments or with misadjusted settings,
the limiter will activate to prevent the channel from clipping. Without a limiter, high
signal conditions would overload the channel and cause distortion.
Adjust the LIMITER THRESH control to a point above your normal operating levels, but
safely below levels causing distortion or “pegging” of the VU meters.
METERING
The MX422 features two calibrated, backlit VU meters. VU (Volume Units) meter ballis-
tics correspond closely to how the human ear perceives loudness and provides a good
visual indication of how loud a signal will be. The attack and decay of the meter signal
is 300 mS. The indicated level on the meters is referenced to +4 dB.
SLATE TONE AND MICROPHONE
The Slate Tone and Microphone circuit is used to notate scenes at the mixer location.
The Slate circuit uses the front panel momentary button. When this button is pressed,
a 20Hz tone is sent to the Main Outputs, and the Slate Microphone becomes active.
When notating a scene - press and hold the Slate button, speak into the four-holed
Slate microphone, and release.
1kHz TONE
This oscillator is provided to set the gain structure between the MX422 and the next
device in your signal chain. The Tone oscillator is set to output a 1 kHz sine wave to
the Main Right and Left outputs (with the Output Level switch set in the out or LINE
position). Note this tone is also sent to the Headphone outputs when the Headphone
SOURCE button is in the MAIN position. It would be a good idea to remove your head-
phones or earphones when the Tone button is pressed in. When levels are set, press
the Tone button again to disengage the Tone oscillator.
QUICK START GUIDE
For those familiar with ENG or fi eld mixers, this guide highlights basic functionality to begin
operating your MX422.
POWERING
To power the MX422 and get it ready for operation:
1. Insert four 9-Volt alkaline batteries into the battery compartments. Insert with the correct
polarity. NOTE: Only one pair of batteries is being used at a time. The other pair is a backup. More
on that later.
2. Or, connect external DC power (the Rolls PS27s) VDC to the MX422 DC Input connector.
3. Press in the POWER button.
4. Check battery life by pressing the BATT button.
INPUT CHANNEL SETUP
To set up a gain level for an input channel:
1. Connect a signal source (microphone or line level signal) to a channel input connector.
2. Set the rear panel trim control at the 12 O’clock position (this is just a starting point).
3. If you’re using a condenser microphone, activate the Phantom Power by pressing in
the phan button.
4. Set the LEVEL Control at the 12 O’clock position (again - just a starting point).
5. Set the channel PAN control for the desired signal position in the stereo fi eld.
6. Press in the rear panel “low cut” switch if needed.
7. Verify there is signal present on the output meter(s).
OUTPUT CONNECTION
To connect to the MX422 main Outputs
1. Connect an XLR cable to the LEFT and RIGHT Outputs of the MX422.
2. Set the output level switch to either LINE (switch out), or -30 dB (switch in).
3. Verify that the next device in the signal chain is receiving signal from the MX422.
HEADPHONE MONITORING
1. Connect stereo headphones or earphones to the HEADPHONE outputs on the front panel.
NOTE: THESE MUST BE STEREO HEADPHONES OR EARPHONES - USING MONO PHONES WILL
DAMAGE THE MX422.
2. Select the Phones signal SOURCE (monitor either the Main signal; switch out, or Monitor
Input; switch in).
3. Set the PHONES level to 0.
4. Verify signal in the phones by slowly bringing up the PHONES level control.
5. Set the PHONES level control for a comfortable level.
METERING
1. View the Main RIGHT and LEFT output signal levels on the ref. +4 dB VU meters.
2. To check the available battery voltage - press the BATT TEST button.
LIMITING
1. For no limiting at all, turn the LIMITER THRESH control completely clockwise.
2. To set a limiting point, send signal through the MX422 and slowly turn the LIMITER THRESH
control counter-clockwise until the desired amount of limiting is acheived.
