Crest Audio XRM - 12 owner manual Str Line In Mic Pad, SUM Inputs Stereo-specific

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Stereo Input channel 2

Front panel features

The XRM features four, full-function Stereo Input channels.These inputs are labeled S1 thru S4 and are located

directly left of the master section. Each stereo channel features two mic preamps, so mic-level stereo sources can be processed on one common channel. In cases where just a mono source is present, the SUM INPUTS switch allows a mono source (plugged into either left or right input) to feed both sides of the stereo chan- nel, effectively turning the stereo channel into an additional mono channel for the mixer.This SUM INPUTS switch also permits the operator to collapse a stereo signal to mono if necessary.

The Stereo channels are very similar, front-panel wise, to the Mono channels. In most cases, the controls will be identical and the descriptions are repeated here.Any Stereo-specific or Stereo-different controls will be identified as such and further described.The rear panel differs in the amount of jacks offered per channel. Because of space limitations, there is no Channel Insert jack available on the Stereo Channels.

Str Line In (Mic Pad)

With this switch in the UP position, the input preamp circuits are set up to accept mic-level signals. These signals are brought in via the XLR mic-input connectors located on the rear panel. The 1/4" TRS input jacks are ignored.

When the switch is depressed, a Pad is inserted into each of the signal paths and the input preamp circuits are capable of accepting line-level signals from either the XLR mic-input connec- tors or the 1/4" TRS input jacks, located on the rear panel.The XLR signal is normal'd to the 1/4” TRS jack. If nothing is plugged into the TRS jack, the XLR signal is fed to the preamp when the LINE switch is pressed. Since the TRS signal is always padded down by 26dB, this feature allows the LINE switch to act as a PAD switch for bringing a very hot microphone signals down to a controllable level, avoiding overload.When a plug is inserted into a 1/4" TRS input jack, the XLR mic-input signal is disconnected and the signal present on the 1/4” plug is fed to the preamp. If plugs are inserted into both the XLR and TRS jacks, this switch acts as an input selector switch between the two jacks.

Gain

The Input gain control is used to establish proper gain structure in the channel. For best results, use the Solo system to monitor the channel while you set the gain.The goal is maximum gain without distortion. Both the main LED meters (during Solo) and the channel’s Level/Peak indicator can be used for adjusting gain.

SUM INPUTS (Stereo-specific)

By summing the inputs, a stereo input channel can be used as a mono input channel.

The channel functions as a stereo input; left input signals feed the left side of the Stereo channel, right inputs feed the right side.

If signals are applied to both the Left and Right input jacks, they will be summed together as a mono signal and fed to both sides of the Stereo channel.This sum-point is directly after the input preamps. If a signal is applied to just one of the input jacks and this switch is pressed, that lone signal will feed both sides of the channel and it will be treated as a mono signal throughout the mixer.

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Contents Rackrack mount mixers XRM 12 Output Monitor Mixer Important precautions Table of contents XRM block diagram Control Icons How to use this manualModule Controls Block diagramHz Lo-Cut filter Lo Cut SwitchLine Input Mic Pad GainXRM Mono Input Module Low frequency-LF High frequency-HFHigh mid-HM Low mid-LMMaster Faders Chan Fader Block diagramModule Mix Sends 1 Mix 1 4 PREMute Channel Level and Control Mute Switch UP, LED OFFMute Switch DOWN, LED on PeaK / SIGnal LEDRear panel ConnectorsXLRMic Input jack Pin-1 Lift Switch+48V On Line Input jackMono input channel Mono Input channel Module Controls Stereo input channelSUM Inputs Stereo-specific Str Line In Mic PadSUM Front panel features Stereo EQ UT Module Master Faders Chan Level Chan SendsMix Send features XRM Stereo Input Module Front panel features Balanced Line Inputs Rear panel ConnectorsSplit-Out XLR jack Master section Solo Meters L & R Solo SystemHeadphone jack Phones Headphone/Monitor Level ControlBlock diagram- Mix Outputs Module Block diagram- Common Input12V Lamp jack STR Pair switchCommon Input Common Input LevelOutput Masters Master Fader Mix Output Level Peak/Signal LED + AFL Switch & indicatorMix Inserts and Outputs Bus InputsPage Solo and Monitor Circuits Rear panelMonitor Output Other Inputs and Outputs Common InputSolo Link Connectors Tie Mixers together AC Input Connector Pinout detailSolo Link Audio LinkingXLR Female Specifications Crest P/N D7000028