The Rolls Bellari PA555 is a tube preamplifier for line-level sources including DAC, phono stage/pre, CD players, and mobile devices. It sports three sets of stereo RCA inputs and a 3.5mm input for computers, smartphones, and other appropriate sources. With the onboard switch, you can choose among the inputs and route them to the stereo RCA outputs.
The PA555 uses a 12AX7 tube running at 150 volts. The input signal is connected directly to the grid of the tube, resulting in all gain from the 12AX7 tube. The PA555 has a no feedback circuit or integrated circuits in the audio path; it is a direct, all analog signal path. The Rolls Bellari PA555 includes a 15V power supply.