Naim Audio ND 555 (+ 555 PS DR)
The Naim Audio ND 555 is the first network player of the 500 high-end series – it replaces the CD 555 reference CD player, which expired about a year ago, but in terms of design and feel it can be said that although the high-resolution display of the Uniti models has been adopted for the completely redesigned device, the developers, apart from this welcome innovation, have essentially oriented themselves towards the Classic series. This also applies to the processing quality, so that the ND 555 fits seamlessly into existing Naim setups in every respect.
Finally, a glance at the rear panel reveals the two-part connection panel: On the far left you will find all digital interfaces – Ethernet socket, USB input, two optical TosLink inputs, two digital coaxial inputs (Cinch and BNC) and three antenna sockets (2x WiFi, 1x Bluetooth with aptX HD). On the other hand, a classic stereo RCA output and the proprietary Naim 5-pin DIN socket are waiting for a connection.
This arrangement already gives an idea of the separation of the two sections inside the housing, which we will discuss in more detail in a moment. First of all, of course, the unusual connection between the power supply has to be mentioned. To guarantee an optimal performance Naim did not use an internal power supply, as for example with the CD 555, instead, you need the external power supply component 555 PS DR (formerly under the name CD 555PS). We do not want to take a closer look at the power supply at this point. Interested parties are referred instead to the corresponding whitepaper with further information.
Technical Finesse
Back to the ND 555: While the changes on the outside are limited, the situation under the hood is different. The first striking feature here is the already mentioned separation of the analogue and digital sections, each of which also has its own decoupled brass sub-chassis – the analogue components rest on a generously dimensioned brass foundation, the digital circuit elements are concealed in a completely closed chamber. Nevertheless, of course, there is information about what is going on inside Two Burr-Brown PCM1704U-K digital-to-analogue converters (the filter and oversampling algorithms come from Naim itself) work together with a fourth-generation SHARC DSP processor and the exclusive NP800 streaming card, which ensures particularly interference-free signal transmission thanks to the LVDS standard. The clocking of the entire digital section now takes place exclusively via the clock of the DAC, so that jitter errors are radically minimized.
On the other hand, the finest analogue technology can be found. Particularly noteworthy here are the thirteen discrete voltage regulators, each of which supplies all modules separately with a constantly optimum voltage. According to development manager Steve Sells, this principle was taken over from the Naim Statement series and now contributes to the excellent sound performance of the ND 555.
Connections & Functions
The new streaming player is thus ideally equipped to refine signals from various sources and, as you would expect from Naim, of course, all important protocols and platforms are also supported. UPnP allows you to manage and play your own digital music libraries from a compatible server via the ND 555 (max. 384 kHz at 32 bit or DSD128). In addition, Apple AirPlay, Chromecast, Roon, Spotify Connect and Tidal have integrated ex-works. The possibility to receive countless radio stations over the Internet is of course also given.
The most important functions can be accessed via the supplied classic remote control or on the device itself. The Naim app for Android and iOS offers full control and maximum convenience. Since the complete control system is also designed bi-directional, all control units are always up to date, making it easy to switch between the various options.
ND5 X2 S & NDX 2
Finally, let’s take a look at the two other models: Basically, these take over many elements of the ND 555 – for example, the converter, which is available here in a simple version. The basic concept of the digital section was also retained but placed differently in the housing for space reasons. In return, both the ND5 X2 S and the NDX 2 have an integrated power supply, the NDX 2 can optionally be equipped with 555 HP DR. The ND5 X2 S has no display and no other controls on the device.
Final Thoughts
With the ND 555, Naim Audio has developed a streaming player that plays at the highest level, from the technical concept to the sound implementation and operation. Thanks to the combination of continuity in design and consistent further development of the technology, the ND 555 is a good reason to enter the Naim world and is also an excellent addition to older setups. Our expectations for the other models ND5 X2 S and NDX 2 are accordingly high.
By the way: You can also get an impression at our HiFi & Friends Fair 2018!
