Crest Audio X 18R, X 20R 48V Phantom Power, Line Input Jack, XLR Mic Input Jack, Chan Insert Jack

Mono Input Channel 1

Rear Panel Features

48V Phantom Power

+48 volts DC is applied equally (thru current-limiting resistors) to both pins 2 and 3 on the mic-input XLR connector. This feature is used with condenser microphones and active direct boxes that require an external DC voltage (phantom power) in order to operate. For dynamic or ribbon mics, phantom voltage is not required and should be switched OFF.

NOTE 1: Operating this switch (On or Off) causes large voltage swings to occur at the input of the mic preamp. Care should be taken to insure that the channel is muted or the main faders are pulled down to prevent this POP from getting to someone’s ears.

Line Input Jack

Line-level signals, balanced or unbalanced, may be brought into the input channel through this 1/4” TRS jack.The LINE switch (front panel) must be pressed for this jack to be active.The XLR jack is normaled to the switching contacts of this jack. If nothing is plugged into the jack, a padded XLR signal is available to the channel when the LINE switch is depressed.This allows the LINE switch to perform a dual function: XLR pad if nothing is plugged into the Line jack, or XLR (Mic)/Line input selection if the jack is being used.

Tip is Positive Input, Ring is Negative Input, Sleeve is Chassis Ground Input impedance is 20K￿ balanced

XLR (Mic) Input Jack

This balanced, female XLR accepts a low-impedance microphone signal or a line-level signal, depending on the position of the LINE INPUT switch on the front panel.

Pin-2 is Positive Input, Pin-3 is Negative Input, Pin-1 is Chassis Ground Input impedance is 4K￿ balanced

Chan Insert Jack

This switching 1/4” TRS jack allows an external signal processor to be inserted into the signal path of the channel.The tip carries the SEND signal from the channel, and the ring carries the RETURN signal back to the channel. The insert-send point is located directly after the Lo-Cut filter on the channel, and the return comes back into the channel at the top of the EQ section.

Tip is Send, Ring is Return, Sleeve is Audio Ground Send (output) impedance is 50￿

Return (input) impedance is 5K Nominal Operating Level= +4 dBu

NOTE: To avoid any degradation of the mixer's channel signal, any processing gear patched into the insert path should have a low impedance output (<100) and must be capable of cleanly driving a 2K load to +21 dBu.

DIRECT OUT Jack

The channel signal can be brought out of the console via the direct out jack. The signal that appears at this jack is normally post fader.There is an internal option for making it pre fader.

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