User manual QSC AUDIO RMX 1850HD

[. . . ] The lightning flash with arrowhead symbol, within an equilateral triangle, is intended to alert the user to the presence of uninsulated "dangerous voltage" within the product's enclosure that may be of sufficient magnitude to constitute a risk of electric shock to humans. CAUTION: To reduce the risk of electric shock, do not remove the cover. WARNING: To prevent fire or electric shock, do not expose this equipment to rain or moisture. What are the differences among Stereo, Parallel Input, and Bridge Mono modes? [. . . ] Avoid excessive signal level, and make sure the wiring and speaker can handle the power. ⷠIf the load is 4 ohms or less and prolonged overloads occur, the amplifier will probably mute for several seconds during peaks, and the circuit breaker may trip. Use four screws and washers when mounting the amplifier to the front rack rails. Support the amp at the rear also, especially in mobile and touring use; rear rack mounting ear kits are available from QSC's technical services department or by special order from your dealer or distributor. Balanced signals are less prone to AC hum, but unbalanced signals can be suitable for short cable runs. The signal source's output impedance should be less than 600W to avoid high frequency loss in long cables. Unbalanced inputs: Connect the unused side of the balanced input to ground, as shown below left. For two-channel (stereo) operation, use the inputs for both Channel 1 and Channel 2; for parallel or bridged mono operation, use the Channel 1 input. see the section on operating modes for more explanation. To patch the audio signal to other amps (parallel and bridged modes only), see the instructions for using parallel inputs on page 9. The RMX amplifier offers a choice of output connections, with two Neutrik NL4MD Speakon jacks and two pairs of "touchproof" binding posts. The upper Speakon jack has both Channel 1 and Channel 2 outputs, so it is especially useful for parallel, biamp, or bridged mono operation (see bridged mono operating precautions on page 11). For easier insertion, use the newerstyle NL4FC Speakon connectors with quicklock thumb latches. SPEAKER CABLING Larger wire sizes and shorter lengths minimize both loss of power and Do not place speaker cables next to input wiring. WARNING: To prevent electric shock, do not operate the amplifier with any of the conductor portion of the speaker wire exposed. Strip back insulation not more than 13 mm (½ inch). WARNING: To prevent electric shock, do not operate the amplifier with any of the conductor portion of the speaker wire exposed. SPEAKER CABLING Larger wire sizes and shorter lengths minimize both loss of power and degradation of damping factor. Do not place speaker cables next to input wiring. Make sure you connect the amplifier to the correct AC line voltage, which is shown on the serial number label. Connecting to the wrong line voltage is dangerous and may damage the amplifier. Before applying power, check all connections and turn down the gain controls. [. . . ] Make sure the "Parallel Input" and "Bridge Mode" switches are OFF in dualchannel, bi-amp, or stereo use where different signals go to each channel. ⷠMake sure other equipment in the signal path, such as mixers, preamps, etc. Cables with faulty shielding are a frequent entry point for hum. Unplug the amplifier input to confirm that the hiss is coming from the source or a device upstream; erratic or popping noises indicate an electronic fault in the offending unit. [. . . ]