SAFETY WARNINGS AND GUIDELINES For best results, please thoroughly read this manual prior to use, paying particular attention to the warnings in this Safety section: Do not expose this device to water or moisture of any kind. Do not place objects containing liquid on or near this device. Do not expose this device to fire or other heat sources. Do not install it on or near heat sources, such as ventilators, radiators, or near a fireplace. Do not place objects with open flame, such as lit candles, on or near this device. This device contains no user-serviceable parts. Do not open or attempt to modify this device. Use only the included AC power adapter or an exact replacement (24 VDC, 1.5A). Take care to ensure that the power cord does not get crimped, kinked, pinched, stepped on, or otherwise damaged. Take care that the cord cannot be a trip/fall hazard. When unplugging connections, always grasp the connector head. Never pull on the cord or wires. Never connect speakers rated for less than 4-ohms to the amplifier in stereo mode. Never connect a speaker rated for less than 8-ohms to the amplifier in bridged mono mode.
OVERVIEW This compact and powerful amplifier is packed with advanced features, yet is rugged enough for commercial environments where a 100% duty cycle is required. It uses an efficient Class D amplifier design, occupies little space, and requires no ventilation. It provides either 20-watts (RMS) of power into two channels or 40-watts (RMS) in bridged mono mode. It accepts two line level inputs and features an internal Bluetooth receiver as a third input. A switchable limiter provides protection against distortion and clipping when used near full output, while the switchable contoured loudness circuit boosts low- and high-frequency signals at lower volume levels. A 9-pin RS-232 serial interface allows the amplifier to be controlled using a PC. For best results, please thoroughly read this manual prior to use. Keep this manual in a safe place for future reference. FEATURES Bluetooth receiver for wireless audio from portable devices Bluetooth connectivity with a built-in microphone for hands free communication with portable phone 3.5mm stereo line level input RCA stereo line level input Signal limiter prevents distortion and clipping Contoured loudness circuit boosts low- and high-frequency signals at lower volume levels Electronic control of BASS, TREBLE, VOLUME, and BALANCE Selectable stereo or bridged mono operation 12 button IR remote control Easy push speaker grip terminals Removable Bluetooth antenna with RP-SMA connector
SPECIFICATIONS Power Output: Frequency Response: Signal to Noise Ratio: Input Sensitivity: Input Impedance: Power Requirement: Dimensions (HxWxD): 20 watts (RMS) per channel into 4 ohm loads 20Hz to 20kHz (-3dB) -95dB @ 1kHz (4 ohms) 330mV (17W 4-ohms) 10 kilohms 24VDC, 1.5A (AC Adapter included) 1-7/8" x 5-5/8" x 4-3/4", including knobs and connectors PACKAGE CONTENTS After receiving the product, please inventory the contents to ensure you have all the proper parts, as listed below. If anything is missing or damaged, please contact Monoprice Customer Service for a replacement. 1x 20-watt per channel amplifier 1x IR remote control 1x AC power adapter IR REMOTE CONTROL The included IR remote control provides convenient access to most functions found on the front panel of the amplifier. Source Selection: LINE1, LINE2, Bluetooth Mute: ON/OFF Power: ON/OFF Treble: UP/DOWN Bass: UP/DOWN Balance: LEFT/RIGHT
CONTROLS AND CONNECTIONS Front Panel Stereo/Bridge: Selects stereo or mono bridged operation. In bridged mode, the amplifier provides one 40W RMS output channel, capable of driving an 8-ohm load. Source: Pressing this button toggles between LINE1, LINE2, and BLUETOOTH sources, as indicated by the LED indicators directly above the button. Select: Press this knob to select VOLUME, BASS, TREBLE, or BALANCE. The LEDs above the knob indicate the current selection. Turn the knob to adjust the level of the selected function. Bluetooth: Press this button to perform Bluetooth functions. See the Bluetooth section below for details. Power: Pressing this button toggles the unit ON and OFF. Rear Panel RS-232: For connection of an external serial control device, such as a PC Antenna: For connection of the included Bluetooth antenna. NOTE: Use extreme care in handling this delicate antenna. DIP Switches: Loudness: Boosts high and low frequency signals at low volume levels. The effect of this diminished as the volume setting is increased. Once the volume reaches 70% of maximum, this control has no effect. Limiter: Automatically reduces input sensitivity as the amplifier approaches its maximum output level. This prevents distortion and clipping when the amp is used near full output. Because this does tend to reduce the overall dynamic range, it is recommended that this not be used in high fidelity applications. Note: After changing the DIP switches, the amp must be temporarily unplugged from its power source for the changes to take effect. Line 1: Stereo 3.5mm TRS jack for connecting the headphone output of mobile devices.
Line 2: Left and right RCA jacks for connecting consumer audio devices, such as CD or tape players, tuners, and other devices with RCA line level outputs. Speaker Output: Easy push speaker grip terminals for connecting speakers. Normally you would connect a single pair of 4- or 8-ohm speakers. However, because this amp can drive 4-ohm loads, you can connect two 8-ohm speakers in parallel to each output channel. To do this, simply insert two wires into each spring terminal. BRIDGED MODE This amplifier normally delivers a 20 watt output to each of two channels. However, it is possible to "bridge" these two channels, thereby creating a single channel with 40 watts output. This is useful in environments where maximum output power is desired and stereo separation is unnecessary (such as in public address situations). Note that in bridged mode, the amplifier can only drive an 8-ohm or larger load. Do not connect a speaker rated for less than 8 ohms. With the amplifier powered OFF, slide the front panel switch to the BRIDGE position. On the rear, connect the wire from a single speaker to the RIGHT channel's negative (-) terminal and the LEFT channel (+) terminal. The remaining two speaker output terminals will not be used. BLUETOOTH CONNECTION To connect your Bluetooth equipped mobile device to the amplifier, perform the following steps: 1. With the amplifier powered ON, press the SOURCE button repeatedly until the BT indicator lights. 2. When BT is selected, you will notice the red indicator above the BLUETOOTH button blinking. The amplifier is ready to pair with your device. 3. On your mobile device, ensure that Bluetooth is enabled. Scan for nearby devices and select the Monoprice AMP entry. On some devices you may be asked for a passcode. Enter 0000 (four zeroes). On some devices you may need to manually connect to the amplifier after pairing is complete. In some cases you may need to press the Bluetooth button on the amplifier to connect. 4. To disconnect the pairing, press and hold the Bluetooth button for about 3 seconds. Once it is unpaired, the amplifier is ready to pair with another device.
PHONE CALLS This amplifier is equipped with a built-in microphone, allowing you to use it as a handsfree communications device: To answer an incoming call, press the Bluetooth button. To reject an incoming call, press and hold the Bluetooth button for about 3 seconds. To hang up after completing a call, press the Bluetooth button. RS-232 INTERFACE Following are the control commands for the RS-232 interface: 1:9600.n.8.1 <CR>: Enter Key <Esc>: Escape Key <Space>: Space Key 2: Host respond prompt: PA> 3: Show All PA Status: Type: Now<CR> 4: Power On/Off control: Type: Power<Space>On<CR>------Power On Power<Space>Off<CR>------Power Off Power<Space>Toggle<CR>------Power toggle control 5: Mute On/Off control: Type: Mute<Space>On<CR>-------Mute On Mute<Space>Off<CR>-------Mute Off
Mute<Space>Toggle<CR>-------Mute toggle control 6: Volume control: Type: Volume<Space>xx<CR>----Volume xx (xx range 0-79) 7: Source control: Type: Source<Space>x<CR> x=1/2/3 8: Treble control: Type: Treble<Space>xx<CR>-----xx :Treble control (+7 0-7) 9: Bass control: Type: Bass<Space>xx<CR>-------xx :Bass control (+7 0-7) 10: Balance control: Type: Balance<Space>xx<CR>----xx :Balance control (L9 0 R9) 11: Save memory now: Type: Save<CR>----stores all current setting other than power on/off status