Integrated amplifier with bass, treble, and balance adjustment functions. - Model: Integrated Amplifier - Adjustment Functions: Bass, Treble, Balance adjustable - Output Level Display: Equipped with LED meter - Speaker Connections: Speaker A, B, (A+B not possible) On/Off switchable The tuner and AUX button lamps do not light up (they work). I don't have a microphone, so I don't know. Loudness works. Headphone jack works. I have never used the B speaker terminals. Thank you for viewing.