In appearance Conrad-Johnson’s PV4 is distinctly plain: a basic black and silver box with a few simple knobs and buttons. The controls are logically laid out, clearly labeled, and work properly. The two channels track well through the volume control, maintaining balance; pushbuttons and control knobs have a smooth, solid feel (except for the noises audible through the system when switching inputs). Don’t forget the turn-on and turn-off thumps mentioned above; the PV4 is the only one of the preamps I review in this issue—the others are the Audible Illusions Modulus ($450) and the Counterpoint SA-7 ($595)—that lacks a mute switch.… Read the full article