Pro-Ject Phono Box S3 B Phono Preamplifier - Black

Highly Affordable Fully Balanced MM.MC Phono Preamp

The Pro-Ject Phono Box S3 B is an entry-level phono preamplifier that offers a fully balanced design in a neat, small package. Pro-Ject packed this tiny chassis to the brim with high-end features. One of those is Pro-Ject's new True Balanced Connection, which formerly were exclusive to Pro-Ject's RS product series. The Phono Box S3 B brings those features to an incredible new entry level phono preamp.

True High-End Defines a New 'Entry-Level'

The Phono Box S3 B comes in complete new casework. The bigger size enables Pro-Ject to bring a completely new feature set that was never seen before in this price range. The new steel and aluminum case also offers very high rigidity and isolation against outside interferences, which is essential for the new technology inside.

Phono Box S3 B allows you to connect up to two turntables simultaneously – all parameters for each input get stored in the memory. You can perfectly match the Phono Box S3 B to a wide variety of cartridges. Use the gain setting to accurately match the output to other sources like CD players or streaming devices. Ultra-low values like 50 pF or 10 ohms accommodate a wide range of possibilities.

Balanced by Nature

The balanced, symmetrical design is the fundamental standout feature of the Phono Box S3 B. Connect your turntable via the 5-pin mini XLR cable and enjoy the benefits of a balanced signal path. A truly balanced gain stage can extract the final musical information, effectively filtering out any noise from interferences stemming from our noisy, modern homes – such as household appliances, WiFi, Bluetooth, and audio amplifiers.

Cartridges are balanced signal transducers by nature. Due to the internal wiring of MM cartridges, you'll need to upgrade your turntable with an MC cartridge if you want to access the entirety of that balanced signal. Any Pro-Ject turntable with RCA, miniXLR, or 5P outputs is fully compatible with the Phono Box S3 B.

Fully Discrete and Symmetrical Gain Stage

The new Phono Box S3 B gain stage uses a fully discrete layout. A discrete circuit is composed of disparate electronic components and individual devices. The amplifier section is built of single parts and doesn't use any integrated circuits. That makes for an extended and more costly design process, but it results in the best sound quality. The fully symmetrical gain stage can optimize the signal-to-noise ratios, feeding the semi-passive RIAA equalization stage with an exceptionally clean signal.