The MTX48 is the four-zone version of the MTX series, featuring two balanced microphone inputs with a priority function, phantom power capability, and three-band tone control. It includes four stereo line-level inputs for connecting any line-level music source such as a CD player, tuner, or MP3 player. Additionally, there are two wall panel inputs for both line and microphone signals. The MTX can be controlled through additional control panels, its fully functional web-based interface, or the iPhone/iPad Remote app. The RS232 port ensures compatibility with any home and industrial automation systems that support RS232. The front panel of the MTX includes a rotary button for each zone, with indicator LEDs for accessing controls and settings. A built-in PFL loudspeaker allows for pre-listening to every channel without the need for headphones. The balanced line-level zone output connections use 3-pin Euro-terminal block connectors, each accompanied by an RJ45 connector for connecting additional wall panels for that zone. A 24-volt power connection enables the MTX to operate on emergency power, even if the main power is shut down.