The number of digital streaming devices available to the hi-fi enthusiast continues to grow on an almost daily basis. Each player seems to have a distinct musical character and its own particular selection of features. Take the new Naim NDX, for example.
This truly versatile machine provides network music replay, internet radio, digital iPod/iPhone connectivity and USB playback straight out of the box.
Its integral DAC is available to external sources – CD players, set-top boxes and the like – through three S/PDIF inputs. There is also an optional module for any buyer who wants to include FM/DAB radio.
DAC magic
The player follows Naim tradition in being performance-upgradeable through the addition of an XPS or 555PS power supply, along with the external Naim DAC.
You should probably regard adding the DAC as an icing-on-the-cake move, because the integral DAC in the NDX is based on the same technology and its performance does not lag too far behind. It uses the same innovative, SHARC DSP-based buffering with fixed clocks, along with Naim's proprietary 16 times oversampling and low generated noise, digital filtering algorithms.
The three S/PDIF inputs – two transformer-isolated coaxial and one buffered optical – will all accept signals at up to 24-bit/192kHz resolution.
To stream music from computers and NAS (Network Attached Storage) units, the NDX uses the well-established UPnP (Universal Plug and Play) protocol. Naim has also written its own version of this for its sources, the HDX and UnitiServe, which can also act as UPnP servers.
We tested the NDX using these and the more widespread Asset and Twonky servers installed on two NAS drives. The NDX will operate wirelessly 'for convenience' but offers its finest and most reliable performances when connected by wire.
As Naim says: "Delivering music over a network is not difficult, but doing it well requires an attention to detail that is still surprisingly rare in today's market."
If you are prepared to pay for a player that boasts numerous features including extensive isolation to ensure the pristine transfer of data, along with Naim's legendary exacting retentiveness about the smallest of details, why should attaching it by a length of Cat5 or Cat6 cable pose any problems? Using wireless with an NDX seems on a par with fitting remould tyres to a Lamborghini.
The player will stream WAV, FLAC, AIFF, AAC, Windows Media formatted content, ALAC (from iPod), Ogg Vorbis and MP3 files from any appropriate UPnP server or USB-connected storage device.
The iPod connection is especially noteworthy: it is Apple-authenticated and it bypasses the DAC in the device and feeds a digital signal directly to the NDX and its rather more sophisticated and painstakingly optimised Burr-Brown PCM1791A DAC circuitry. This, for example, uses very similar RAM buffer and master-clock jitter-removal techniques as the 'big' Naim DAC.
The NDX, like other digital components in Naim's range features a Ground Selector switch that needs setting according to the rest of the components in your system to avoid earth loops that can, in the worst case, cause audible humming or, in less severe instances downgrade the sound. It has two options: to connect the earth to the chassis or to leave it 'floating'.
If you have a Naim CD player in your system, the floating selection is correct for all other Naim components where a choice is offered. If you are including the NDX in a predominantly non-Naim system, you'll need to take you dealer's advice or trust your ears.
Read more:
http://www.techradar.com/reviews/audio-visual/hi-fi-and-audio/audio-systems/naim-audio-ndx-940186/review#ixzz1J2Bq9uqx
