JBL PRX900 Series, User Manual

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• To compensate for different distances’, determine the speaker farthest from the audience and delay other
speakers with the same signal to “time align” with the speaker farthest away from the audience.
• Sound travels through air at average humidity and room temperature at about 1.1 feet per ms. Measure the
difference in distance of each speaker feeding the audience. Feed the speaker farthest from the audience with
no time alignment delay. Set delays for the other closer speakers based on their distance ahead of the farthest
back speaker. Measure the distance difference and enter 1 ms per 1.1 feet that each speaker is ahead of the
farthest back speaker in your configuration. Time alignment is not perfect as not all audience positions measure
the same speaker distance differences.
•
The PRX915/918XLF offer 20ms of speaker delay on it’s input stage.
•
Polarity – This inverts the polarity of the subwoofer. OFF indicates the woofer is in standard polarity. ON means the polarity
of the subwoofer is reversed.
Settings
• BT Control Pairing” enables Bluetooth control pairing for up to 30 seconds with the JBL Pro Connect app. This turns off
when a pairing has been made, or after 30 seconds. When pairing with the app, please initiate control pairing first. Select
the speaker in the “Add Speakers” menu. The speaker will send a 4-digit pin back to the LCD. Confirm this using the MAIN/
MENU knob.
•
“LCD Contrast” allows the user to adjust the LCD contrast between 0 and 100%.
•
“Firmware Version” shows the current firmware version loaded onto the speaker.
• “Factory Reset” resets all settings in the speaker to factory default, including Bluetooth communication pairing.
• BLE Firmware Version - this is the version of BLE firmware loaded on your speaker.
•
“System lock” locks out all hardware operation from the speaker.
•
To initiate system lock, press and hold the POWER button and the BACK button until all LEDs flash and a LOCK icon
appears in the top left corner of the LCD.
OR
Navigate to the System Lock field in the settings menu, and select CONFIRM.
• To disable system lock, press and Hold the POWER button and the BACK button until all the LEDs flash the lock icon
disappears from the top left corner.
OR
Remove AC power and reboot the system.