The Rolls Bellari PP532 is a preamp for audiophiles. It handles input switching and volume control without introducing any powered elements that might cause distortion into the signal. Indeed, this is a passive design: no power is required, and no active electronics are in the circuit path.
The device's steel chassis houses four sets of RCA inputs in stereo pairs for your music sources, while one set of RCA connectors routes to your amplifier. A four-way selector on the front of the panel allows you to select among the inputs.
You'll notice that the front panel provides the option of plugging into a 3.5mm phone jack. This setup makes it convenient for routing signal from your smartphone or media player into the preamp without having to go round the back. The volume knob sports a Bosin potentiometer to ensure precise level adjustments. The device is hand-built in the USA, in Salt Lake City Utah. It's relatively compact at 5.5 x 3.1 x 1.6".