Rockville RPA70WBT is a professional mixing karaoke amplifier with Bluetooth, AM/FM digital tuner, USB, and 2 wireless microphones. It features a 2-channel amplifier with 125W per channel at 4 ohms or 100W per channel at 8 ohms, making it ideal for powering 4 speakers. With its built-in preamplifier, digital karaoke system, and various input options, the RPA70WBT is perfect for a wide range of applications, from home karaoke to professional sound reinforcement.