VOX AMPHONESBASS Active Amplifier Headphones Headphones with built-in am Plug technology that allows you to obtain lead tone immediately Headphones made by Audio-Technica, the trusted name in headphones The headphone amp uses a new reactor circuit thats based on the Valve Reactor technology featured in Vox amps, delivering incredibly dynamic lead tone Totally analog design that faithfully simulates the circuit response of the original amp The Bass version which provides a wide-range sound, including a new Bassilator circuit that realistically simulates the resonance of the speaker cabinet and floor.