1. Multifunction stereo amplifier: The KS33BT is a versatile and powerful stereo amplifier, delivering 60W 60W rated power and a maximum output of 400W. It features adjustable treble, bass, and echo, along with SD, USB, AUX, and MIC inputs. Compatible with CD, DVD, TV, and PC audio sources, it supports passive speakers and active subwoofer stereo outputs. Included is a 110V/60Hz power cable for easy setup. 2. fidelity amplifier: Engineered for HiFi sound enthusiasts, this amplifier incorporates dual amplifier chips and advanced sound processing technology to ensure low distortion and fidelity audio. Adjustable treble, bass, and echo settings allow for some level of sound adjustment, while the builtin equalizer optimizes output for speakers or subwoofers, delivering exceptional sound quality. 3. Mic input and echo function: The KS33BT Bluetooth stereo amplifier doubles as a karaoke amplifier, featuring two microphone jacks and echo effects. Whether enjoying music or hosting a karaoke session with family and friends, this amplifier provides entertainment at home. 4. Bluetooth 5.0 FM radio: Equipped with Bluetooth and FM antennas, this subwoofer amplifier includes a Bluetooth 5.0 chip for stable, noise connectivity (range: up to 5 meters; beyond this, Bluetooth disconnects automatically). Additionally, the FM function allows you to tune into your favorite radio stations anytime.