Manufacturer: SHIDU. PROFESSIONAL MICROPHONE AND SPEAKER: The sound can cover 22,600 sq.ft(2100 m2) and reach up to 300+ people indoors. No noise, distortion or whistling. STEREO SOUND QUALITY POWER AMPLIFIER: Wireless voice amplifier built-in dual-magnetic large-caliber speakers, voice amplifier shocking stereo surround sound, treble loud and clear, midrange clear and dynamic, bass strong and powerful.
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