The AV-1900 is a highly capable mixer-amplifier packed with useful features to make it as easy as possible to operate. It is designed for use in demanding applications like meeting spaces, small auditoriums, lecture theatres, school halls, and small churches. It has professional audio features normally only found in much more expensive mixer amps. Bluetooth For ease of connectivity it has a Bluetooth input. The device name and pin are fixed and cannot be changed. It can only pair with one device at a time. A device can be manually unpaired by pressing the INPUT 3 dial. If you do not want Bluetooth active just set input 3 to mic input with the switch on the rear. Mixer Amp This amp has four inputs, each of which can either be used for a microphone or a line-level input. It is a true mixer amp, so it can bring together multiple sources and play them at the same time. Mic Pre-Amp Trim The input gain for each mic input can be “trimmed” – adjusted on the rear panel. This allows the installer to “turn up” less sensitive mics, and “turn down” hot inputs. Four Microphone Inputs All mic inputs are “balanced” to eliminate electro-magnetic noise induced on long cables. Input 1 uses a professional XLR connector – more convenient for rental and portable use, and the other inputs use phoenix connectors – more suited to permanent installations. Switchable Phantom Power Each mic input has Phantom power which is a voltage required to make professional condenser mics work. Phantom can be turned off on each input discretely. RS-232 Designed for integration with a bigger system, it can be controlled by a control system such as Techconnect Control via RS-232. D-Class An efficient Digital-class amplifier chip dramatically reduces power consumption especially at rest, and makes this amp super-small. 3 x Stereo Inputs Three line-level stereo inputs accept input from a variety of sources such as computers (via the headphone jack), tablets or phones. Inputs 1 and 2 use 2-phono (RCA) connectors. Input 4 is via a Minijack connector, and is duplicated on the front panel for adhoc access. Line Output A line-level pre-output on the rear bypasses the internal amplifier. It would connect to a larger amplifier or powered loudspeakers. It is post-mix; volume adjustments made on the front panel affects the output level. Auto-Standby If the amplifier senses no input it will automatically go into standby mode. When it senses input it will reactivate. Auto-standby can be disabled via RS-232. Mounting Options Rack ears are included so it can be integrated into an AV rack.