The Dayton Audio HTA20BT combines the efficiency and power of solid state class D amplifier topology with the warmth and character of a vacuum tube preamp section. The results are a delightfully articulate and natural sound that is sure to please even the most refined ears.We stand behind our products and our warranty is a demonstration of our commitment to quality and reliability.Key FeaturesTube warmth, class D efficiencyBluetooth 4.2, Aux, and USB inputsSubwoofer output for adding an active subwooferHigh quality headphone amplifier built inE