Pro-Ject Phono Box S3 B Black

Fully Balanced Phono Stage with XLR Output

The Pro-Ject Phono Box S3 B is the balanced-output flagship of the Phono Box S3 range, distinguishing itself from the standard Phono Box S3 with a fully symmetrical, differential gain stage and true balanced XLR outputs. Where the standard S3 routes the signal through a conventional single-ended circuit, the S3 B takes the cartridge's naturally balanced output and preserves it in a fully balanced signal path all the way to the output connectors, delivering significantly lower noise and greater dynamic contrast.

Built around an all-discrete, symmetrical gain stage, the S3 B supports both MM and MC cartridges and offers wide-ranging loading adjustments on the front panel, allowing precise matching to virtually any cartridge. Two inputs can be connected simultaneously, each with its own stored settings, which is ideal for users with more than one turntable. Pro-Ject's True Balanced Connection system means that when used with a compatible balanced turntable cable and 5-pin mini XLR input, the cartridge signal is handled in a fully balanced manner from stylus to amplifier input.

The S3 B is housed in a new, larger steel and aluminium casework that enabled Pro-Ject to include features previously unavailable at this price point. Gain is selectable at 40, 45, 60 or 65 dB (with an additional 6 dB on tap when using the XLR outputs), a subsonic filter at 20 Hz with 18 dB/octave slope reduces turntable rumble effectively, and a comprehensive set of input impedance and capacitance options covers all practical cartridge types. Both standard RCA and balanced XLR outputs are provided simultaneously, giving flexibility in system integration.

Key Features

• Fully discrete, symmetrical (balanced) gain stage throughout
• Balanced XLR and standard RCA outputs provided simultaneously
• 5-pin mini XLR input for Pro-Ject True Balanced Connection
• Front-panel cartridge loading: impedance and capacitance selectable
• Stores settings for two turntable inputs
• Subsonic filter at 20 Hz, 18 dB/octave
• Steel and aluminium casework; handmade in Europe