COMM-TEC MMA220B mini amplifier RS232-controllable

The COMM-TEC MMA220B stands out among compact amplifiers by pairing genuine RS232 control with a robust Class D stereo output, making it a practical choice for installations where remote command and small size matter more than raw wattage. Unlike typical mini amps that only offer front-panel knobs, this unit integrates cleanly into automation systems while delivering dependable 20W per channel into 4-ohm loads.

Highlights

• RS232 serial control for integration with AV control systems
• Class D amplification for high efficiency and low heat
• 2 x 20W RMS into 4 ohms, suitable for bookshelf or ceiling speakers
• Dual analog inputs: RCA stereo and 3.5mm jack
• Bass and treble adjustments for tonal tailoring
• Auto-standby reduces power consumption when idle
• Metal housing with surface-mount capability

In daily use

The MMA220B fits neatly behind a display, under a desk, or in a small rack. Connect a source via RCA or 3.5mm, wire speakers to the Phoenix screw terminals, and adjust volume, bass, and treble either locally or through RS232 commands. The auto-standby feature powers down the amplifier after a period of silence, saving energy without manual intervention. Thermal, over-current, and short-circuit protection ensure reliable operation in continuous duty.

Full specifications

• Amplifier class: Class D
• Channels: 2 (stereo)
• RMS power per channel @ 4 Ohm: 20W
• Total RMS power @ 4 Ohm: 40W
• Frequency response: 20Hz – 20kHz
• Signal-to-noise ratio: >80dB
• Total harmonic distortion: <0.1%
• Input sensitivity: 200mV
• Input impedance: 10k Ohm
• Audio inputs: 2x RCA stereo, 1x 3.5mm stereo jack
• Speaker outputs: Phoenix screw terminals
• Control interfaces: RS232, IR
• Power supply: DC 12V, 2A (external adapter included)
• Bass adjustment: Yes
• Treble adjustment: Yes
• Volume control: Rotary
• LED indicators: Power, standby
• Housing material: Metal
• Mounting: Surface mountable
• Protection: Over-current, over-temperature, short-circuit

Final note

For integrators and hobbyists who need a small, controllable stereo amplifier with clean sound and reliable protection, the MMA220B offers a compelling balance of features and footprint.