&#127822[Updated Version] UPDATED on 25 April 2018. The new version adopts 2 pcs TI TPA3116 chips which has stable and reliable quality and can provide 100W *2 RMS output power. Really clean sound quality. The old version may stop working after 3 weeks use, please contact us at customer@fosiaudioshop.com for exchange if you received the old version. Bluetooth 4.2 core, up to 33ft connection range guarantees low signal delay. No pop, no audible noise when Bluetooth connection is established; 100W RMS X 2(4 ohms, 20 Hz - 20 kHz, 0.04% THD), comes with 19V power supply, can drive 280watts(8 ohm), 320watts(4 ohm) speakers;