Naim Audio StageLine black

Derived from the phono cards that used to equip Naim preamplifiers, the StageLine embodies the British manufacturer’s decision to move this function into a dedicated enclosure. This separate phono stage is precisely matched to moving-coil and moving-magnet cartridges thanks to four distinct technical variants. It requires a 24V power supply provided either by a compatible Naim amplifier or by a separate power supply unit.

From internal cards to a separate enclosure

For many years, Naim preamplifiers incorporated modular phono cards. The NAC 32, 42, 62, and 72, produced from the 1970s through the 1990s, housed plug‑in modules available in S, K, and N versions depending on the cartridge. The move toward more compact chassis led Naim to externalize this function.

Launched in the early 2000s, the StageLine reprises the core, time‑tested circuitry of the old cards in a standalone box. This approach allows owners of non‑Naim systems to enjoy the qualities of the brand’s phono stage, provided they purchase a compatible power supply.

Construction and components

The machined aluminum chassis measures 57 × 121 × 187 mm and weighs 7 kg, a figure unusual for this category. This mass is explained by the robustness of the metal construction, chosen to shield the circuits from electromagnetic interference. The matte black anodized front panel reflects Naim’s signature design language.

Inside, a thick fiberglass printed circuit board carries the discrete‑component electronics. Naim favors this approach over integrated circuits to achieve better noise‑floor performance. The gain stages use bipolar transistors combined with electrolytic and tantalum capacitors, while the RIAA equalization components are built to strict specifications: polystyrene capacitors and metal‑film resistors with 0.1% tolerance.

The rear panel includes two gold‑plated RCA sockets bolted to the chassis, a ground terminal, and two DIN connectors (four‑pin for the output signal, five‑pin for the power supply). The manufacturer supplies the appropriate cables.

Four versions for precise matching

The StageLine is available in four factory‑configured variants, each optimized for a specific category of cartridge.

The N version is intended for moving‑magnet cartridges and high‑output MCs. With an impedance of 47 kΩ and a sensitivity of 2 mV, it delivers 35 dB of gain at 1 kHz.

The S version targets low‑output MC cartridges, with a sensitivity of 100 μV and an impedance of 470 Ω. Gain reaches 60 dB at 1 kHz. Technical sources mention a high‑frequency roll‑off above 22 kHz.

The K version shares the same 100 μV sensitivity but offers an impedance of 560 Ω. Naim initially developed it for Linn moving‑coil cartridges, notably those built by Supex. It maintains a wider bandwidth than the S.

The E version is a compromise, with a sensitivity of 400 μV and an impedance of 400 Ω (some sources indicate 560 Ω). It suits medium‑output MC cartridges, avoiding excessive gain.

Power supply: the decisive factor

The StageLine has no internal mains transformer, in line with Naim’s philosophy of keeping stray magnetic fields away from sensitive audio circuits. The unit requires a 24V supply provided by external sources.

Integrated NAIT amplifiers (XS, XS 2, XS 3, SuperNAIT and their variants) have a dedicated power socket on the rear panel, as do NAC 152 XS, 202, 282, 252 and 552 preamplifiers. Players in the Uniti range (except NAC-N 172 XS and NAC-N 272) can also power the StageLine.

For use with a system from another brand, or to improve performance, dedicated power supplies are essential. The FlatCap XS is the entry level, followed by the HiCap and the SuperCap. Comparative tests confirm that moving from a shared power supply to a dedicated unit yields measurable gains in dynamics and transient control.

Burn‑in and use

The StageLine requires substantial burn‑in, which can extend over several weeks of continuous use. The manufacturer recommends leaving the system powered on for long periods. During installation, two transport screws hold the board in place and must absolutely be removed before first power‑up. The ground terminal is essential to eliminate hum and unwanted noise.

Positioning in the range and evolution

The StageLine sits at the entry level of Naim’s phono stage range. Above it is the SuperLine, which incorporates a two‑stage discrete class A amplifier with 25 internal regulated power supplies and a spring‑suspension system. Interchangeable loading plugs allow impedance adjustment across twenty standard combinations.

The StageLine’s circuitry is directly inspired by previous generations of phono cards, remaining very close to the NA 322 and NA 323 modules. This lineage explains both its well‑known strengths in terms of rhythm and dynamics, and certain limitations compared with more recent designs. Third‑party modifications exist, offered by Ryan Sound Lab or Avondale Audio, which replace certain components with higher‑grade versions.

Technical specifications

Compatibility

• Moving-coil cartridges (MC)
• Moving-magnet cartridges (MM)

Versions and specifications

S version

• Sensitivity: 100 µV
• Impedance: 470 Ω
• For low-output cartridges

K version

• Sensitivity: 100 µV
• Impedance: 560 Ω
• For selected moving-coil cartridges

E version

• Sensitivity: 400 µV
• Impedance: 400 Ω
• For medium-output cartridges

N version

• Sensitivity: 2 mV
• Impedance: 47 kΩ
• For high-output cartridges

Dimensions and weight

• Dimensions (H × W × D): 57 × 121 × 187 mm
• Weight: 7 kg