The $550 Bluetube Audio vacuum tube amplifier claims to offer true analog sound. For all its retro charm, including 3/4″ thick cherry and walnut enclosures, it comes equipped with an advanced internal BlueTooth receiver with voice command setup, 2 hardwired inputs, Class A push-pull amp, optional titanium full range speakers, and USB charging ports.

Adding speakers to the amplifier brings the price up to $775.