For sale, a built-in amplifier and mixer from the well-known company BTC, model SSA-45E (original Indian made). Very clean used in excellent condition, and works at its full efficiency (on inspection and condition). Specifications: 3 independent microphone inputs with full volume control for each mic. AUX input for connecting a mobile phone or external audio devices. Built-in echo system (Echo) to control the beauty and repetition of the sound. Ability to control tone weights: Bass and Treble. Designed for small and medium spaces (excellent for prayer rooms, schools, and homes).