Safety Instructions

When using this electronic device, basic precautions should always be taken, including the following:

1. Read all instructions before using the product.
2. Do not use this product near water (e.g., near a bathtub, washbowl, kitchen sink, in a wet basement or near a swimming pool etc). Care should be taken that objects do not fall into liquids and liquids would not be spilled on the device.
3. Use this device when you are sure that it has a stable base and it is fixed securely.
4. This product, in combination with loudspeakers may be capable of producing sound levels that could cause permanent hearing loss. Do not operate for a long period of time at a high volume level or at a level that is uncomfortable. If you experience any hearing loss or ringing in the ears, you should consult with an otorhinolaryngologist.
5. The product should be located away from heat sources such as radiators, heat vents, or other devices that produce heat.
6. Note for power connections: for pluggable equipment, the socket-outlet shall be installed near the equipment and shall be easily accessible.
7. The power supply should be undamaged and never share an outlet or extension cord with other devices. Never leave device plugged into the outlet when it is not being used for a long period of time.
8. Power disconnection: when the power cord connected to the power grid is connected to the machine, the standby power is turned ON. When the power switch is turned ON, the main power is turned ON. The only operation to disconnect the power supply from the grid is to unplug the power cord.
9. Protective Grounding - An apparatus with class I construction shall be connected to a power outlet socket with a protective grounding connection. Protective Earthing - An apparatus with class I construction shall be connected to a mains socket outlet with a protective earthing connection.
10. [Warning Symbol: Lightning Flash] The lightning flash with an 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 persons.
11. [Warning Symbol: Exclamation Mark] The exclamation mark within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the appliance.
12. There are some areas with high voltage inside; to reduce the risk of electric shock, do not remove the cover of the device or power supply. The cover should be removed by qualified personnel only.
13. The product should be serviced by qualified service personnel if: The power supply or the plug has been damaged. Objects have fallen into or liquid has been spilled on the product. The product has been exposed to rain. The product has been dropped or the enclosure damaged.

RISK OF ELECTRIC SHOCK

DO NOT OPEN

To reduce the risk of electric shock, do not remove screws. No user-serviceable parts inside. Refer servicing to qualified service personnel. To reduce the risk of fire, electric shock or product damage, do not expose this apparatus to rain, moisture, dripping or splashing and that no objects filled with liquids, such as vases, shall be placed on the apparatus.

Before You Start

The DMPA Light series device is a compact 1U half-rack size public address mixing amplifier, containing a media player with AUX input, FM radio receivers, 1 microphone input, and an emergency mute control. It supports wireless audio streaming from mobile devices. This system is designed for installations, such as gas stations, restaurants, and convenience stores, where easy operation is appreciated.

Features

• Compressed audio playback
• Supports up to 32 GB USB flash and SD cards
• FM radio receiver and wireless audio streaming from mobile devices
• 3-channel mixer with microphone and aux inputs
• Microphone input priority and phantom power
• RCA output
• Stereo RCA AUX input
• Emergency mute
• Amplifier output with phoenix connector
• Supports 100 V and low impedance speaker installations
• DMPA 120 & 240 Light supports 2 Ω speaker installations

Operation

Front Panel

The front panel features the following controls and indicators:

• 1. MIC, AUX & Media player volume: Rotary knob for adjusting the volume level of the microphone, AUX, and media player channels.
• 2. Bass and treble controls: Rotary knobs for adjusting bass and treble frequencies.
• 3. USB drive input: Port for connecting USB flash drives.
• 4. 3.5 mm AUX input: 3.5mm stereo TRS input for auxiliary audio sources.
• 5. LCD display: Shows information such as track number, volume, source, and FM frequency.
• 6. Master volume: Rotary knob for adjusting the overall master volume.
• 7. Mode button: Button to switch between media player modes (e.g., USB, FM, Bluetooth).
• 8. Player control buttons: Buttons for playback control (play, pause, skip).
• 9. Repeat function button: Button to select repeat modes (all, one, random) or save FM presets.
• 10. Media player mute / power button: Button to mute audio or turn the media player on/off.

Rear Panel

The rear panel provides connections for power, speakers, and audio sources:

• 1. Mains power input & fuse holder: Connector for AC power and a holder for the fuse.
• 2. Power switch: Switch to turn the amplifier power ON or OFF.
• 3. Ground connecting point: Terminal for grounding the unit.
• 4. Amplifier output: Connectors for speakers (Phoenix connector).
• 5. DC power supply input: Connector for external DC power source.
• 6. RCA LINE output: RCA stereo output for connecting to external amplifiers or equipment.
• 7. RCA AUX input: RCA stereo input for auxiliary audio sources.
• 8. Phantom power and mic input priority settings: Controls for phantom power and input priority.
• 9. Microphone input: Phoenix connector for microphone input.
• 10. 24 V emergency mute connector: Terminal for connecting an external mute signal.
• 11. FM antenna connector: F-type connector for connecting an FM antenna.

Front Panel Functions

MIC 1 / AUX / PLAYER LEVEL CONTROLS

Rotary knobs for adjusting the volume level of the selected channel.

BASS & TREBLE TONE CONTROLS

Tone controls provide attenuation of bass and treble response. The flat position is obtained when the knobs are set to the middle position. Turning the knob clockwise raises the tone level approximately +7.5 dB for bass and +10 dB for treble; turning counter-clockwise lowers the tone level by approximately -7.5 dB for bass and +10 dB for treble.

AUX INPUT

3.5 mm stereo TRS input for an auxiliary audio source. Select AUX input in the media player to play sound from this input. Volume is controlled with the "PLAYER" level control knob on the front panel.

MASTER VOLUME

Rotary knob for adjusting the master volume.

Rear Panel Functions

MAIN POWER CONNECTOR AND FUSE

Power connector for mains power, combined with a fuse holder. Use only the same type of fuse that is written on the device.

POWER SWITCH

Switch the amplifier power ON or OFF.

LINE LEVEL AUDIO OUTPUT

RCA stereo output for connecting the device to an external audio amplifier or other equipment. The audio level in this output is not affected by the Master volume.

AMPLIFIER OUTPUT DMPA 30/60

Audio outputs for Low impedance (4 Ω) and Hi-Z (100 V) speakers. Use the DIP switch located in the rear next to the microphone input to enable the amplifier's output type suitable for your installation. Only one output can be used at a time. Especially for small background music systems, we recommend using the 4 Ω output for the best audio quality and frequency reproduction. The Low Z output allows connecting in parallel 4x16 Ω or 2x8 Ω loudspeakers. The amplifier's 4 Ω output is designed without an output transformer and has a 20 Hz-20 kHz frequency response to ensure the best possible audio quality for background music.

AMPLIFIER OUTPUT DMPA 120/240

Audio outputs for Low impedance (2 Ω) and 100 V speakers. Be sure that the correct speaker output is enabled by using the DIP switch located in the rear next to the microphone input. Only one output can be used at a time. Especially for small background music systems, we recommend using the 2 Ω output for the best audio quality and frequency reproduction. The Low Z output allows using 8x16 Ω loudspeakers or 4x8 Ω loudspeakers connected in parallel. The amplifier's 2 Ω output is designed without an output transformer and has traditional 20 Hz-20 kHz frequency responses to ensure the best possible audio quality for background music. Pay attention to wiring on the low Z output! Please use a minimum of 1.5 mm² cables to connect speakers over a short distance. Depending on the audio line length, the cable diameter must be increased in order to minimize voltage drop on the cable.

Rear Panel Functions (Continued)

DMPA 120/240 LIGHT DC POWER SUPPLY INPUT

The amplifier can be powered using an external power source that provides voltage from 24 V to 36 V DC. This is useful for emergency situations or when AC mains power is not available. Voltage at the DC input affects the maximum amplifier's power. The graph shows the relation between the amplifier's output power and the DC input voltage.

Graph Description: The graph displays DC Input Voltage (V) on the Y-axis ranging from 20V to 36V, and Power (W) on the X-axis ranging from 0W to 240W. Two lines represent DMPA 120 Light and DMPA 240 Light, showing increasing power output with increasing DC input voltage.

DMPA 30/60 LIGHT DC POWER SUPPLY INPUT

The amplifier can be powered using an external power source that provides 24 V DC voltage.

OUTPUT IMPEDANCE SELECTOR

This selector sets up amplifier outputs depending on the audio system type. The 100 V mode enables the output transformer and sets up amplifier circuits to adjust and amplify audio optimized for 100 V speaker lines. The 4 Ω (DMPA 30/60) and 2 Ω (DMPA 120/240) modes turn off the 100 V output transformer, in order to connect speaker lines directly from the power amplifier stage. This mode ensures the best amplifier performance and also enables 20 Hz-20 kHz frequency reproduction in order to make low impedance loudspeakers sound as best as they can.

AUX INPUT

RCA stereo input for connecting an external audio source.

MIC INPUT

Phoenix connector for balanced microphone connection.

PHANTOM POWER AND INPUT PRIORITY

The MIC input can provide 18 V phantom power for condenser microphones. This input can also have a priority over other inputs.

EMERGENCY MUTE

When 24 V DC current is supplied to the EMG MUTE input, all device outputs will be muted. This is useful when using the device combined with external alarm systems.

Media Player Functions

LCD SCREEN

The LCD screen displays main information about the media player status: track number and time, media player volume level, music source, and FM frequency.

USB FLASH DRIVE

Supports up to 32 GB USB flash drives formatted in FAT32 file system.

MODE

Switch the player between wireless audio streaming from mobile devices, FM, and USB player modes.

FM ANTENNA

F-type connector for FM radio antenna.

Media Player Functions (Continued)

PLAY/PAUSE

Switch player mode between play and pause. Hold this button in FM mode to start radio station auto scan. Press this button rapidly to toggle FM frequency auto/manual scanning mode.

FORWARD / BACKWARD

A single short press in music mode changes the currently playing track. Holding the buttons for a few seconds increases or decreases the volume level of the media player. In FM mode, use these buttons to change FM frequency in 0.1 MHz steps, and also to switch radio presets.

PLAY FROM USB

When a USB memory stick is inserted into the USB port, the track number and time will show in the display, and audio files will start to play automatically.

REPEAT AND RANDOM PLAY

Select one of three modes: RTA – Repeat all tracks. RT1 – Repeat one track. RND – Random play. The second function of this button is to save the FM radio frequency to a selected preset.

MUTE / POWER

Press this button to mute audio. Hold this button longer to turn the media player on/off.

FM Radio Receiver

The FM radio receiver allows saving 26 presets with selected radio stations. It uses the same control buttons, but with different functionality.

Hidden Functions Diagram Description: The diagram shows buttons labeled MODE, DOWN, MANUAL/AUTO SCAN, UP, SAVE, EXIT, REPEAT, MUTE/POWER. Their functions are described below.

ENTER TO AUTO TUNING MODE

Press and hold the Play/Pause button for a few seconds to scan available stations and store them as presets. Press and hold the Play/Pause button for a few seconds to abort auto tuning.

To step through presets, press the Previous or Next buttons.

ENTER TO MANUAL TUNING MODE

Press the Play/Pause button to enter manual tuning mode. Use the Backward/Forward buttons to adjust the frequency in 0.1 MHz steps. Press the Repeat button to select a preset number and change it using the Backward/Forward buttons. Press the Repeat button again to save the radio station to a preset. Press the Mute button to exit manual frequency adjusting without saving the radio station preset.

Wireless Audio Streaming from Mobile Devices

PAIR

1. Enter wireless audio streaming from mobile devices mode on your DMPA Light media player.
2. Open the pairing settings menu on your mobile device and search for “AMC Player_0000” in the list of available devices.
3. Select “AMC Player_0000” and confirm that it is connected as an audio device.

CONTROL

Backward, Forward, and Play/pause buttons control the audio player on your mobile device. Holding the Backward or Forward buttons will adjust the output volume of the mobile device.

RENAME

Customize the device name by holding the Play/Pause button until "AMC Player_0000" is displayed. It is possible to change the 4-digit part of the name. Press the Backward or Forward buttons to edit the number and Play/Pause to select another character. Hold Play/Pause to save changes and exit.

Android devices have the facility to re-name devices within the settings menu. If the device ID has been re-named on the Android device, editing the device ID on the media player will not affect the name displayed on that Android device.

General Specifications

DMPA Light Media Player Amplifier

The specifications are correct at the time of printing this manual. For improvement purposes, all specifications for this unit, including design and appearance, are subject to change without prior notice.