Фонокорректоры — Pro-Ject Tube Box S3 B

The Tube Box S3 B is a valve phono preamplifier from Pro-Ject Audio Systems, announced in August 2025 together with the smaller Tube Box E. It works with MM and MC pickups and offers balanced connections at both ends of the signal path. Pro-Ject builds it in Europe in an aluminium case finished in silver or black. The list price is EUR 599 or GBP 529, and USD 699 in the United States. Compared with the S2 generation of Pro-Ject phono boxes, it moves to a larger chassis with dual-mono circuitry and upgraded parts.

Key specs that matter

Four gain steps are available - 40, 45, 60 and 65 dB - and the XLR output adds a further 6 dB. Input impedance is selectable at 10, 50, 100, 1k and 47k ohm, and capacitance at 50, 150, 300 and 400 pF. Signal-to-noise ratio is 97 dBV, or 105 dBV A-weighted, for MM at 40 dB, and 83 dBV, or 88 dBV A-weighted, for MC at 60 dB. THD at 1 kHz is below 0.005 percent for MM and 0.01 percent for MC, and across 20 Hz to 20 kHz below 0.1 percent for MM and 0.03 percent for MC, and RIAA accuracy is within 0.4 dB from 20 Hz to 20 kHz. On the rear are a 5-pin mini XLR input and an RCA input, with RCA and XLR outputs side by side. The case measures 206 x 81 x 153 mm, or 164 mm deep with sockets, and weighs 1010 g without its 18 V, 1000 mA supply.

Engineering and use context

Two ECC83, also known as 12AX7, valves sit in the circuit and the owner can replace them. The gain stage is symmetrical and discrete, laid out as dual mono, and RIAA equalisation is semi-passive, an approach Pro-Ject chose for low noise and low distortion. The 5-pin mini XLR input keeps the tonearm cable balanced from the deck onward, which the maker ties to its True Balanced Connection approach for turntables fitted with the same socket. Loading and gain are adjusted from the front panel, and the unit stores its settings in memory. A subsonic filter at 20 Hz with an 18 dB per octave slope cuts very low frequency content such as warp and rumble. In use the unit draws 800 mA and less than 0.5 W on standby.

Pairing

Pro-Ject turntables with a 5-pin mini XLR socket connect balanced, while other decks use the RCA input. Amplifiers with XLR line inputs can take the balanced output.

Alternatives

The Pro-Ject Tube Box E is the compact valve phono stage with a fully discrete dual-mono design, adjustable gain, capacitance and impedance and a front-mounted subsonic filter, priced at GBP 240 or EUR 299.