User manual QSC AUDIO PLX2

[. . . ] PLX Series Professional Audio Amplifiers User Manual 4-ohm minimum impedance models with Speakon® output terminals: PLX 1104 PLX 1804 2-ohm minimum impedance models with Speakon and binding post terminals: PLX 1802 PLX 2502 PLX 3102 PLX 3602 *TD-000214-00* TD-000214-001Rev. C Important Safety Precautions & Explanation of Symbols 1- Read these instructions. 5- WARNING: To prevent fire or electric shock, do not expose this equipment to rain or moisture. 8- Do not install near any heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat. 9- Do not defeat the safety purpose of the polarized or grounding-type plug. [. . . ] ·Set the switch to the rightmost position for driving subwoofers. Low Frequency filter selection table 33 Hz (low cut) / FULL Switch: Unless the loudspeaker has extended low frequency capability, we recommend setting the filter to the 33 Hz setting. The filter should only be set to FULL (turned off) for driving subwoofers. Check the loudspeaker's specifications and use the 33 Hz filter if the loudspeaker's low frequency capability does not extend below 33 Hz. ·Set to FULL when driving loudspeakers that have low frequency capability below 33 Hz or in studio monitoring applications. ·Set to 33 Hz for loudspeakers which are not rated for frequencies below 33 Hz. 6 Inputs Each channel has a balanced XLR (female) and 1/4-inch TRS input. The XLR and TRS connectors for each channel are wired in parallel and can be used for "daisy chaining" an input signal to additional amplifiers. Both XLR and TRS inputs are connected with standard cables and can be changed quickly. Do not attempt to connect more than one input signal to a given channel. Balanced connections are recommended to reduce AC hum and interference, especially with long cable runs. Input connectors and pinout chart (PLX1802 shown) Input Pinouts Balanced inputs: Connect to the plug as shown. XLR TRS PLX 1104 and PLX 1804 models can parallel the input signal to both channels by using a jumper from one channel to the next: Unbalanced inputs: Connect to the plug as shown. If using an XLR connector, Pin 3 and pin 1 must be connected with a jumper as shown. If using a TRS connector, the ring and sleeve must be connected with a jumper. If a TS connector is used, the sleeve will provide the "jumper" when inserted into the input jack. ·Connect the input signal to either of Channel 1's input connectors. ·Connect a jumper from Channel 1's unused connector to either of Channel 2's input connectors. Risk of hazardous energy! 8 LED Indicators The LED indicators can be used to monitor system operation and identify common problems. POWER (PWR): BLUE Normal indication: ·AC switch ON: LED will illuminate. CLIP: RED Normal indication: ·Illuminates whenever the amplifier is driven beyond full power. Abnormal indication: ·Bright red illumination while the amp is being used indicates either thermal muting or a shorted output. [. . . ] ·In Bridge Mono, the amplifier may shut down for several seconds if driven too hard into loads less than the rated 4-ohm minimum. ·If the amplifier overheats due to prolonged overload or high external temperature, it will mute for about 30 seconds with the fan running at full speed for maximum cooling. Make sure the rear intake is getting a free flow of cool air. PLX 1104/1804 models: ·These models have completely automatic internal protection that maintains operation even under extreme conditions. If driven constantly into clipping, internal circuitry smoothly reduces the volume to minimize distortion and stress. [. . . ]