Фонокорректоры — Einstein Audio Components THE PHONOSTAGE

The Phonostage is an MC-only phono amplifier made in Bochum, Germany, by Einstein Audio Components. It takes a hybrid approach inside the Einstein phono range - the input stage is a discrete design built from 10 single transistors, while the two following amplifier stages use op amps. The brand lists its own cartridge, tonearm and record player as matching products.

Key specs that matter

Gain is 68 dB (2500 times) or 74 dB (5000 times), chosen with jumpers. The S/N ratio is over 80 dB at 1 mV and 1 kHz. Distortion measures below 0.05% at 1 mV and 1 kHz, and channel balance is within 0.5 dB, both without any feedback. Headroom is 10 dB, with a maximum input of 3 mV at 1 kHz. The RIAA curve is corrected passively at high frequencies and actively at low frequencies. Output impedance is 100 ohm and maximum output is 8 V RMS. Input loading can be set up to 2 kohm, with any value possible through resistor plugs. The chassis measures 215 x 360 x 150 mm in height, depth and width and weighs 6 kg.

Engineering and use context

Einstein builds the unit as a double mono design, keeping the left and right channels apart for channel separation. A floating ground scheme, used across the brand, is there to avoid hum loops, and shielding plus the circuit layout aim to keep hiss and noise away from the small signal a moving-coil cartridge produces. The power supply is sized with large headroom, so it can deliver well beyond what the amplifier stages draw. Both adjustments avoid DIP switches in the signal path. Loading is changed by inserting custom RCA plugs fitted with resistors into sockets on the rear panel, and the two gain values are selected with a simple jumper, which Einstein prefers over a noisy switch contact. The lower gain setting suits higher output moving-coil cartridges, and the higher one is meant for low-level models. Combining passive and active equalisation splits the RIAA work between the passive network at the top of the band and the op amp stages at the bottom.

Pairing

With its low maximum input level, the Phonostage is aimed squarely at moving-coil pickups rather than moving-magnet ones. The low output impedance and generous output swing suit the high-level input of any preamp or integrated unit, and the resistor plugs allow the load to be matched to the coil impedance quoted by the cartridge maker.

Alternatives

The Einstein Phonoamp uses a fully discrete 48 transistor circuit with fixed gain and an external dual mono power supply.