The NDX2 is a network audio player that succeeds the original NDX by introducing a completely redesigned streaming platform. This Classic Series model features a Burr-Brown PCM1792A DAC, an LVDS-based network card, and a 5-inch color display, while retaining the option to upgrade with a dedicated external power supply.
A streaming platform redesigned from the ground up
The NDX2 takes over from the NDX by incorporating the developments made for the Uniti range. The main advancement lies in the new network card, which uses LVDS (Low-Voltage Differential Signalling) technology. This low-voltage differential signaling system transmits digital audio data over two wires by using the voltage difference between them rather than an absolute measurement. This approach significantly reduces electrical noise and allows higher data rates with lower power consumption.
The NDX2’s network card takes control of data clocking, unlike previous generations where the source imposed its own clock. Digital signals pass through an SHARC DSP processor that performs upsampling with 40-bit precision before sending the signal to the digital-to-analog converter.
The DAC chosen is Texas Instruments’ Burr-Brown PCM1792A, renowned for its 127 dB signal-to-noise ratio and high dynamic range. Naim adds its own digital filters and places a discrete-component current-to-voltage converter immediately after the DAC instead of using the DAC’s built-in circuits. This approach allows for better control of the analog signal path.
The built-in power supply is centered around a custom-designed toroidal transformer with separate windings for the digital and analog sections. Total filtering capacitance reaches 53,000 µF. A proprietary Burndy connector nonetheless allows you to connect an external XPS DR or 555 PS DR power supply to improve performance, in keeping with Naim’s tradition of separate power supplies.
A touchscreen and a bidirectional remote control
The NDX2’s front panel features a 5-inch TFT color display that shows album artwork, track information, and navigation menus. A proximity sensor automatically turns the screen on when you approach the device. Four physical buttons round out the front interface, along with a type-A USB port delivering 1.6 A for playing USB drives or portable audio players.
The supplied remote control uses Zigbee RF4CE technology, a bidirectional radio protocol that enables two-way communication. The device can thus send visual confirmations back to the remote. This Zigbee system also opens up compatibility with other connected devices from the same ecosystem, such as certain smart lighting systems.
Control is mainly handled via the “Focal & Naim” app available on iOS and Android. This app manages all the player’s functions, including setting up multiroom modes and managing playlists. For compatible Naim amplifiers equipped with the RC5 system, the app even lets you control volume and inputs directly from the mobile interface.
Connectivity designed for every use
The rear panel of the NDX2 reveals comprehensive connectivity to suit a wide range of setups. On the digital input side, there are two Toslink optical inputs accepting signals up to 24-bit/96 kHz, one coaxial RCA input, and one BNC coaxial input, both supporting up to 24-bit/192 kHz. These inputs allow the NDX2 to be used as an external DAC for a CD player, Blu-ray player, or any other digital device.
A BNC coaxial digital output makes it possible to delegate conversion to an external DAC if the user prefers this configuration. A second type-A USB port is located at the rear, complementing the one on the front. Network connection is established either via 10/100 Mbps Ethernet through the RJ-45 port, or via 802.11 a/b/g/n/ac Wi-Fi thanks to the two supplied external antennas.
On the analog output side, there is a pair of stereo RCA outputs and a 5-pin DIN output, Naim’s characteristic connector that favors a short signal path. An infrared output on a 3.5 mm mini-jack allows you to extend remote control range in a multiroom installation. The Burndy connector for the external power supply completes the feature set.
The brushed and anodized aluminum chassis measures 432 mm wide, 314 mm deep, and 87 mm high, with a weight of 10 kg. This construction carries forward the timeless aesthetics of the Classic Series, with its understated front panel and imposing metal sides.
High-resolution formats up to native DSD
The NDX2 plays WAV files up to 32-bit/384 kHz, FLAC and AIFF formats up to 24-bit/384 kHz, and ALAC (Apple Lossless) at the same resolutions. Compressed formats MP3, AAC, and M4A are supported up to 48 kHz at 320 kbit/s in 16-bit. The player also handles OGG and WMA up to 48 kHz in 16-bit, as well as DSD64 and DSD128 files.
Via the digital inputs, the NDX2 processes S/PDIF signals up to 24-bit/192 kHz and supports DSD64 via DoP (DSD over PCM). This extensive compatibility allows you to play virtually any music library, whether sourced from ripped CDs, high-resolution purchases, or streaming.
Network streaming is based on UPnP certification to access files stored on a NAS, computer, or dedicated server. The Roon Ready protocol offers full integration with Roon servers, enabling browsing enhanced by the metadata and analysis provided by these systems.
Upgrade paths toward true high-end performance
The NDX2 sits between the entry-level ND5 XS 2 and the ND 555, which represents the top of Naim’s network player lineup. This hierarchy allows gradual upgrades according to budget and ambition. Adding an XPS DR power supply is the first upgrade step, bringing better current management and reduced noise.
The even more capable 555 PS DR power supply offers a second level of improvement. This modular approach reflects Naim’s philosophy, which considers the power supply to be a decisive factor in sound quality, often more important than the circuits themselves.
The NDX2 can also serve as a stepping stone to the ND 555, the flagship network player that shares the same streaming platform but uses even more sophisticated components and construction. This upward compatibility protects the initial investment and allows coherent progression within the Naim ecosystem.
