Фонокорректоры — Unison Research UPHONO+

The uPhono+ is a compact phono preamplifier from the Italian company Unison Research that combines an analogue MM and MC stage with an analogue to digital converter, three digital outputs and a headphone amplifier in one small box. It lets a turntable feed a conventional line input, a computer for vinyl archiving, a digital input on a DAC or streamer, or a pair of headphones directly, and it sells in the UK at GBP 1,100.

Key specs that matter

Gain for moving magnet cartridges is 38 dB at 1 kHz, while the moving coil stage offers 58 dB or 69 dB, chosen by dip switches. MM loading is 47 kOhm with capacitance of 100, 200, 320 or 420 pF, and the MC input can be set to 5, 10, 25, 100, 250, 500 or 1,000 ohm. RIAA accuracy is within 0.3 dB from 20 Hz to 30 kHz. Distortion at 1 kHz is 0.018% for MM with 10 mV in and 0.12% for MC with 1 mV in. Signal to noise is quoted at 80 dB for MM, 64 dB for MC at 58 dB gain and 60 dB at 69 dB gain. Nominal line output is 316 mV RMS from an 824 ohm output impedance, and overload margin is 30 dB. The chassis measures 82.5 mm high, 216 mm wide and 251 mm deep and weighs 2.8 kg.

Engineering and use context

Two line outputs are fitted, one fixed and one variable, and the variable level follows the front volume knob, which is an Alps Blue Velvet potentiometer shared with the headphone stage. With this arrangement the uPhono+ can feed a power amplifier or powered monitors without a separate preamplifier when vinyl is the only source. A subsonic filter to the IEC standard rolls off below 20 Hz at 6 dB per octave to limit warp and rumble energy. The digital section converts the phono signal at 16 or 24 bits and sample rates from 8 kHz to 96 kHz, and sends it over USB to a computer, over Toslink optical and over coaxial S/PDIF at 0.5 V peak to peak into 75 ohm. Analogue and digital circuits have independent power supplies, and the board uses surface mount parts. Mains versions exist for 220 to 240 V and 100 to 120 V.

Pairing

The 6.35 mm headphone jack accepts loads from 16 to 600 ohm and delivers up to 2.18 V RMS with 0.07% THD plus noise at 1 kHz into 32 ohm. The two MC gain steps suit both mid output and very low output coils, and the wide resistor range covers most moving coil designs. The USB link lets a laptop record LPs straight to files with no extra interface.

Alternatives

The Unison Research Simply Phono is a two box valve phono stage with four ECC83 tubes, a passive RIAA network and an external power supply.