Фонокорректоры — Kora PHONOSTAGE

The Phono Stage is the first standalone phono preamplifier from Kora of Toulouse, a company whose technical director is Bruno Vander Elst. Unlike the valve-based 140 series, it is a solid-state design derived from the EPC1 D, an ultra-low-noise laboratory preamplifier made by the professional division of Kora. It handles moving magnet, moving coil and variable reluctance cartridges, and its French price was EUR 6,600.

Key specs that matter

Four inputs can each be programmed separately. Inputs 1 and 2 use XLR sockets and work either balanced or unbalanced, while inputs 3 and 4 are RCA and unbalanced only. Gain is set as a multiplication factor in seven values - 150, 300, 500, 750, 1,000, 1,500 and 3,000 - rather than in decibels. Load is 50 kOhm for MM or anything from 10 to 1,270 ohm in 10 ohm steps, and capacitance runs up to 1.5 nF in 0.1 nF increments. Input noise is 70 nV across the audio band, RIAA accuracy is within 1 dB, and maximum output reaches 8 V RMS. Two RCA and two XLR outputs can feed separate devices at once, with an output impedance under 50 ohm. The chassis is 320 x 75 x 260 mm, or 320 x 91 x 280 mm overall, and the unit weighs 5 kg while drawing less than 10 VA.

Engineering and use context

Kora set out to reach the lowest noise without resorting to a step-up transformer. The fully symmetrical first stage uses very low-noise input transistors rated at 0.5 nV per root hertz and offers a gain of 50 or 100. Every resistor in the signal path is a Vishay VSRJ metal foil part with tolerances down to 0.01 %. A second stage converts the balanced signal to single-ended by subtraction, rejecting common-mode noise, and adds a gain of 3. Treble equalisation is done passively with polystyrene capacitors, and an active circuit using the same capacitor type handles the low-frequency correction. The output stage adds four more gain settings of 1, 3.33, 5 and 10, and a phase splitter creates the inverted signal for the balanced jacks. Per input, the screen lists gain, load, capacitance and connection type, and the settings return from memory at switch-on. A rumble filter set to -6 dB at 7 Hz helps with warped records, and a demagnetising mode acts on all four inputs while a record plays for half an hour. If mains power disappears, the output is muted at once.

Pairing

With four inputs, two turntables or a deck with two arms can stay connected, each with its own cartridge profile. The factory settings give 1,500 and 200 ohm for MC on inputs 1 and 3, and 150 and 50 kOhm for MM on inputs 2 and 4.

Alternatives

For a PR140 owner, the Kora Phono module is the nearest alternative, a slide-in drawer with a single RCA input switchable between MM and MC.