he MA40 is a very compact mono amplifier designed for integration into installed audio and AV systems where de-centralisation of system components is advantageous. It is intended as an “install-andforget” component, and is small enough to be fitted into a wall or ceiling void, or in any convenient location adjacent to a projector, flat screen display or loudspeakers, for example. A simple set of controls and configuration options makes it easy to integrate into any audio system. It is highly suitable for use with in-store digital signage, gallery and museum exhibits and fixed or mobile tour guide systems. The MA40 can drive 40 W into a 4 ohm load when used with the external 24 V mains PSU supplied with the amplifier, but it will operate from any external DC supply of between 12 and 24 V, making it ideal for installation on buses, trams, river boats, or anywhere an AC mains supply may not be readily available. The maximum output power is reduced with supply voltages below 18 V. The power amplifier stage is fully protected against DC offset, over-current, over- and under-voltage and is also thermally protected. A switch-on delay function mutes the output during power-up and power-down to protect loudspeakers. The amplifier mixes two unbalanced stereo line inputs with a balanced microphone input; the stereo inputs are summed to mono internally (the music channel). LINE 1 can be set to have priority over LINE 2 via a rear panel DIP switch to allow the connection of message stores, etc. The mic input can be configured (by another DIP switch) to automatically take priority over the line inputs when a mic signal is present, allowing its use for announcements. 12 V phantom power is available at the mic input, selectable by internal jumper. Front panel controls are provided for MIC, LINE 1 and LINE 2 levels; additionally there are LF and HF EQ controls for the music channel which allow the amplifier’s response to be optimised to suit the loudspeakers and acoustic environment. A PEAK LED illuminates if the amplifier’s dynamic clip protection becomes active, and thus clearly indicates the onset of distortion .On the rear panel, each line input has a preset control for gain, while the mic input has both preset gain and LF and HF EQ controls. A dedicated remote level control port is provided to permit the output level to be controlled by a standard Cloud RL Series remote control plate. In common with most Cloud products, a Music Mute Input is provided, which may permit compliance with local Fire Authority regulations; the microphone input remains active when the Music Mute is applied. A front panel MUTE LED illuminates if the Music Mute function becomes active. The MA40 is very energy-efficient* and draws very little power in a quiescent state. A user-selectable automatic power-down function puts the amplifier into an ultra-low-current standby mode after a preset period with no signal. A bicolour front panel LED indicates standby and active statuses.
Cloud MA40 Features
Compact mono amplifier module for “install-and-forget” situations • Two (unbalanced) stereo line inputs with individual sensitivity trims • Electronically-balanced mic input with separate gain control • Phantom power selectable by internal jumper • Front panel control of music level and mic levels • Front panel HF & LF EQ adjustments for music sources • Rear panel HF & LF EQ adjustment for mic input • Selectable MIC-over-LINE priority • Selectable LINE 1-over-LINE 2 priority • 40 W power amplifier • Optional EQ cards available to suit various popular installation loudspeakers Remote level control port; compatible with Cloud RL Series plates • Music Mute input; selectable N/O or N/C • Automatic power-down function (user-selectable) • Less than 1 W power consumption in sleep mode • Convection cooled – silent in operation. • PSU meets US DoE Level VI energy requirements • Power requirements: 12 to 24 V DC, 47 W • Universal AC adaptor included, operates from 100 to 240 V AC.
Cloud MA40 Specifications
Line inputs Frequency Response ±1 dB, 20 Hz to 20 kHz Distortion <0.1 % Sensitivity -12 dBu to +8 dBu Input Gain Control 20 dB range Input Impedance 10 kohms (unbalanced) Headroom >12 dB Noise <-90 dB Equalisation LF: ±10 dB @ 50 Hz, HF: ±10 dB @ 10 kHz Microphone input Frequency Response -3dB @ 120 Hz (filter) to 20 kHz ±1 dB Distortion <0.1% Gain 10 dB to 50 dB Input Impedance >2 kohms (balanced) Headroom >12 dB Noise <-90 dB Phantom Power +12 V (internal jumper) Output Output Power (1 kHz continuous sine wave) 40 W, DC input >18 V
