Фонокорректоры — Pro-Ject Phono Box

The Phono Box is a compact MM and MC phono stage made by Pro-Ject Audio Systems, and the company calls it a best buy classic in its Box Design range. It is meant for systems whose amplifier has no dedicated phono input - the Phono Box applies RIAA equalisation and gain, then feeds a line input such as AUX. The front plate comes in black or silver, and the box is small enough to stand close to the record player.

Key specs that matter

A switch on the rear panel sets the cartridge type. In MM mode the input presents 47 kohm and 120 pF, and gain is 40 dB, so 3 mV at 1 kHz produces 300 mV at the output. In MC mode the input load is 100 ohm with the same 120 pF, and gain is 60 dB, turning 0.3 mV into the same 300 mV. Maximum output is 9.5 V at 1 kHz, leaving large headroom above the nominal 300 mV level. Pro-Ject gives a noise floor of 94 dBA for MM and 75 dBA for MC, and THD of 0.01 percent and 0.05 percent respectively. RIAA accuracy stays within 0.5 dB between 20 Hz and 20 kHz. Power comes from an external 18 V, 200 mA DC adapter, with standby draw below 1 W. The box measures 103 x 36 x 104 mm, or 115 mm deep including the sockets, and weighs 570 g.

Engineering and use context

The gain stages use low noise integrated circuits, and Pro-Ject specifies an ultra-low impedance for the output stage, which helps the preamplifier drive longer interconnects and different amplifier inputs without loss of level. Keeping the mains transformer outside the case in a DC wall supply removes a source of hum from the sensitive input circuit. All connections are gold plated RCA sockets. There are no load or capacitance adjustments beyond the MM and MC switch, which keeps operation simple but means the owner accepts the fixed values listed above. The compact footprint lets the stage sit on the same shelf as the turntable, which keeps the tonearm lead to the preamplifier short and limits pickup of hum from other equipment.

Pairing

Any moving magnet cartridge designed for the standard load fits the MM position. For moving coil types the fixed MC load and higher gain suit typical low output models, while very low output coils may need more gain than this box provides. The line outputs connect to any integrated amplifier, preamplifier or active speaker with an analogue input.

Alternatives

The Pro-Ject Phono Box S2 adds switchable impedance from 10 ohm to 47 kohm, four gain levels between 40 and 63 dB and a subsonic filter in a dual mono layout.