Phono Stages

What a Phono Stage Does

A turntable cartridge produces a signal far too small for the line input of an amplifier, and records are cut with the bass reduced and the treble lifted. Rega sums up the task: a phono pre-amplifier matches the cartridge to a line level amplifier, amplifying the very low signal and equalising the sound to the RIAA record cutting standard. Manley describes the second half of that work as restoring the originally intended flat response.

Where an amplifier has no phono input, a dedicated phono preamplifier is essential; where one is built in, a separate phono stage can be chosen to suit the cartridge in use. The phono stage sits between the turntable and the amplifier, so the choice depends on both, and the turntables in the collection show the range of decks a stage may partner.

Moving Magnet and Moving Coil Cartridges

The cartridge shapes the choice more than anything else. An MM cartridge suits a dedicated moving magnet stage such as the Rega Fono MM MK5, while a moving coil cartridge delivers far less output and needs more gain and careful loading. Rega believes the two types need different phono pre-amplifiers, which is why Rega builds the Fono MC MK4, the Rega Aos MC and the Rega Aura MC as moving coil designs with adjustable loading.

Other phono stages accept both types. Every Lehmannaudio Black Cube is MM and MC capable with a configurable input impedance, the LUXMAN E-250 adds a built-in step-up transformer for moving coil cartridges, and the Naim NVC TT provides a separate input for each.

From Compact Designs to Reference Stages

Rega designs and assembles every phono stage in the UK, from the compact Rega Fono Mini A2D MK2, which also connects to a computer over USB for recording vinyl, to the Aura MC, the reference moving coil stage in the Rega range. Lehmannaudio, founded by Norbert Lehmann in Cologne in 1988, built the first Black Cube prototype in 1995, and the Lehmannaudio Black Cube SE II now pairs the circuit with a separate power supply.

From Japan, the LUXMAN E-07 is an all-solid-state phono equaliser with a balanced input for moving coil cartridges and three power transformers, the flagship of the LUXMAN pair here. Sugden hand-builds the Sugden Masterclass PA-4 in Yorkshire, each unit by a single technician, and calls the design a phono amplifier, with Class A stages for MM and MC.

For a valve presentation, the Manley Oasis is an all-valve design hand-assembled in Southern California, an evolution of the acclaimed Chinook from Manley. The Naim NVC TT belongs to the 300 Series from Naim and draws power from the dedicated NPX TT supply or from a compatible Naim preamplifier.

Choosing the Best Phono Stage for Your System

Begin with the cartridge, because the output and loading that the cartridge manufacturer specifies decide how much gain and adjustment the phono stage must provide. Then look at the amplifier: even an integrated amplifier with a phono stage built in can be paired with a dedicated design, and the right phono preamp for turntable and cartridge alike brings adjustment that a built-in stage may lack. Power arrangements vary too, from the external supplies of the Lehmannaudio range to the internal mains supply of the Rega Aos MC.

A turntable preamp works with the smallest signal in the system, so the phono stages here are best compared with a familiar record. Ask Audio Lounge about a demonstration in London, and for advice on cartridges, cables and the wider analogue collection.