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Pro-Ject Phono Box S3 B


MM/MC Phono Preamplifier with Balanced Output

The New Balanced S3 Phonostage

The Phono Box S3 B comes in a new, larger enclosure. Due to the bigger case, we were able to bring new features to our S3 phono preamplifier. The new steel & aluminum chassis with aluminum buttons brings very high rigidity and effective isolation from interference. The Phono Box S3 B is available in silver and black and is ready for use in any hifi setup.

‘B’ for Balanced

In addition to settings for MM (Moving Magnet) cartridges, the Phono Box S3 B allows you to upgrade to True Balanced operation with a MC (moving coil) cartridge on most Pro-Ject turntables. Balanced transmissions consist of a hot and a cold (also called + and -) signal. Both signal chains effectively carry the same musical information. A True Balanced gain stage can now extract the final musical information out of the +/- signals and subtract the hum and noise picked up during the transmission. This is the same concept used with every microphone in every professional recording studio worldwide.

Not Just Balanced, Also Discrete

The gain stage of the new Phono Box S3 B uses a fully discrete layout. A discrete circuit is composed of electronic components that are separate, individual devices. The amplifier section here is comprised of discrete componentry (no integrated circuits) which results in a more costly and time-consuming process but delivers the best sound quality.

Semi-Passive EQ

After treating the balanced +/- signals independently they are added back together and processed by the semi-passive RIAA equalization stage. By keeping the gain stage fully symmetrical we can optimize signal-to-noise and keep interference to a minimum, sending the EQ section an optimal signal with which it can it can do its job. For the balanced XLR outputs, a balancing stage generates a symmetrical signal so you benefit from balanced signal transmission again. The RCA outputs are by nature single-ended and their signals are served directly by the RIAA EQ.

Cartridge Loading Options

New to the S3 line, all settings can be easily adjusted on the faceplate. You can connect two turntables at the same time. Each input setting is stored in the memory. A large gain range from 40dB up to 65dB is possible. You can match it with a wide variety of cartridges and seamlessly integrate it into the rest of your hifi system, matching the volume levels accurately to other sources like CD players or streaming devices. The loading options for MM and MC are designed for compatibility with a wide array of cartridges. Ultra low values like 50pF or 10 ohms allow you to account for special situations, for example less-than-ideal higher capacitance cables. The Phono Box S3 B has always got you covered!