Bluetooth 5.0 & Stereo RCA & MM Phono inputs: MM phono input, converts phono signal to line level signal and amplify it, with low-noise integrated circuits and high-quality components to ensure clear and clean sound. And provide enough output power for passive speaker, greatly improve the sound quality. JAN5654 vacuum tube & HiFi Sound: default with JAN5654 tubes, improves everything associated with your music such as detail, transparency, immediacy, richness, dynamic, tone etc. Much better than 6J1 series especially in human voice. Pluggable tube socket for tube rolling and sound-shaping, easy to pick from and alter the sound signature to one's preference.