Commercial Audio 240W 5ch 100/70V Mixer Amp with Microphone Priority (

Simplify the task of running distributed audio for restaurants; hotels; or anywhere large areas need background music and/or paging address systems. Connect hundreds of speakers covering acres of area without the need for large equipment racks. A constant voltage speaker system differs from a traditional 8-ohm speaker system in that it uses a step-up transformer at the audio source to raise the voltage and lower the current on the transmission line. At the speaker end; a step-down transformer converts the signal back to a normal speaker level voltage. This reduces power loss during transmission; which allows for the use of longer speaker wire runs using smaller gauge wire. Additionally; a constant voltage speaker system allows for the use of multiple speakers on each channel; without the need for complicated impedance calculations and configurations. In a constant voltage system; all speakers on a given channel are connected in parallel and the complicated impedance calculations are replaced by simple wattage calculations. For example; if you want to connect two speakers per channel in a traditional 8-ohm speaker system; you must either connect them in series; which results in an overall 16-ohm impedance; or in parallel; which results in an overall 4-ohm impedance. In the first case; the 16-ohms impedance effectively halves the output power of your amplifier; resulting in lower overall volume levels. In the latter case; the 4-ohms impedance means that your amplifier will have to work harder and must be rated as stable at 4 ohms. Adding a third speaker to the mix would complicate it further; producing either a 24-ohm or 2-ohm overall impedance. Note that very few amplifiers are stable under 2-ohm loads; so that is usually not an option. On the other hand; with a constant voltage system; you consider first the RMS output wattage of the amplifier. This should be reduced by 20% to compensate for insertion loss. For example; if using a 100-watt amplifier; the total load from speakers should not exceed 80 watts. This amplifier features three microphone inputs and two auxiliary inputs; each of which is active and mixed into the line and speaker level outputs. When an EMC input trigger is detected; all outputs except MIC 1 are muted; allowing for the clear broadcast of important messages. The amplifier can drive a speaker array consisting of one or more speakers presenting a 4~16 ohm load or to one or more 70V or 100V speakers connected in parallel as part of a large public address system. Features: 5-channel (3 microphone and 2 line) mixer/amplifier Amplifier rated for 240 watts 70V; 100V; and low impedance 4~16 ohm speaker output options Built-in rack mount ears and 2U height for mounting in a standard 19" equipment rack Unbalanced front panel input for MIC 1 Both balanced XLR and unbalanced TRS and RCA rear panel inputs for MIC 2 and MIC 3 Phantom power option for MIC 2 and MIC 3 Two unbalanced RCA auxiliary/line inputs Master volume; bass; and treble controls Front panel level controls for all inputs 0-30dB variable muting for all channels except MIC 1 when MIC 1 is in use Built-in short circuit; over-current; and high temperature protection circuits Line level output of mixed signal for connection to other devices