Hardware Reviews

NAD M50 & M52


It seems strange that it has taken until now for me to find a truly high end digital music player that works well. One that bridges the gap between an Ethernet coupled NAS and a digital to analogue converter through a S/PDIF cable. You could either work with a Logitech Squeezebox or you had to look for high end solutions like dedicated music servers with USB out or proprietary ones with their own D/A converter on board. Indeed, a Logitech Squeezebox is not too bad, but in a high end set-up it looks rather out of place. The hi-fi world was crying out for something better.
It must have been difficult to develop and finish the M50 digital music player, it was almost a year after CES 2012 before NAD could supply the first units to the public. The Netherlands had the honour of putting the M50/M52 on the market in December last year (2012), but in limited quantities only.
The M50 digital music player is part of the Master Series by NAD and is designed to be the music streaming partner of the M2 digital amplifier or used in combination with an M51 D/A converter. The M52 is a storage unit for all your ripped music files. However, I soon discovered that one can use the M50 as a source component in any hi-fi system for playing streaming music or internet radio. The only inputs on the M50, (in a stand-alone situation the 12 Volt triggers or the RS-232 port do not count) are for Ethernet and asynchronous USB but there are four types of output: S/PDIF optical and electrical, AES/EBU through XLR and last but not least we find HDMI with PCM output for receivers. Just for sound, not for imaging. Plus one extra USB connection dedicated to the M52 Digital Music Vault. No D/A converter on board, no fancy screen, no amplifier or other electronics. But we do get a CD transport. The four line display shows some basic information, but you need a tablet with the right app for day to day use. Not even the remote will do you any good. On opening the enclosure of the M50 we find just a switching power supply, the CD drive (actually a Sony DVD) and one single printed circuit board with all other electronics. The internal drive is not just there to rip files; you can play your CDs as well. The M50 is a digital music player and a CD transport in one. The very low jitter clock is for both CD and for streaming. The software is kept on an SD card in a slot on the board. With no hard drive inside, the M50 is completely silent.
Let us first focus on the options the M50 has to offer, one of the most important aspects of the M50 is its ability to play any file type (WAV, FLAC, ALAC, MP3, WMA, Ogg Vorbis, AIFF) at up to 24-bit/192 kHz from any input. No matter how you offer your music, USB or on Ethernet, what goes in comes out unaltered. No upsampling, no downsampling. You can store your music on the very quiet M52 Digital Music Vault which connects by USB. Inside the M52 are three 1TB hard disks arranged in a RAID configuration, the storage capacity is limited to 2TB in total. If the M52 is connected it’s possible to rip CDs to these drives. Tags and covers come from the internet, directories are created automatically. The rip process is bit perfect in FLAC and you can rip to MP3 at the same time but there is no option to rip to uncompressed formats.


M52 Digital Music Vault Front
At present the M50 will rip to any FAT or NTFS formatted USB drive. The price of the M52 is rather high for storage only, but there is one more point in its favour. If no wired connection to the internet is possible, only wi-fi, high sample rates might show dropouts. Not when running from the local M52 of course where wi-fi is only used for remote control, CD covers and tagging information. Alternatively rip your CDs to a disk or USB stick, connect it to the M50 and play your music. It works flawlessly although I prefer either Ethernet or the M52 for sound quality reasons (I tried a 1TB Western Digital Passport external HDD and a 32GB Sandisk Cruzer USB stick). Between Ethernet and the M52 I could not hear any difference no matter how hard I tried.
Indexing the music is rather special on the M50. NAD does not use DNLA or UPnP as the index is built inside the M50. If a file is available on several devices, for instance on a NAS and on a USB drive, the M50 index only shows the highest resolution version. Inside the box the M50 might look like a PC running Linux on an ARM processor, but do not fool yourself, the M50 is a music player especially made for high end audio purposes. The big advantage of a software based product is the possibility to upgrade over the web.
It has a few of the usual database peculiarities. For instance on re-indexing the software looks at both tag fields “Artist” and “Album artist”, If they are not exactly the same, you have two entries in the database. A space or capital is enough to make a difference. After a re-index you have to close the app, only a restart from scratch will show your music again. The app is not completely finished it seems, the repeat button is always on and the info button shows only some information on the artist from Last.fm. Other brands (Naim and PS Audio) do a better job. If you dim the display, the music stops playing and you do need to dim it since long track names keeps scrolling in blue text. I often complain about remote controls, I cannot read the small print, NAD is even worse, white letters on grey fields! Not even a spotlight makes the text clear. But that is all I have to criticise. I hope someday NAD will improve those items (they already did some in new software releases).



NAD M50 PCB including SD card next to the company logo

I didn’t try all file formats, just FLAC, ALAC and WAV, with bit depths of 16 and 24 bits and sample rates between 44.1 (ripped CDs) and 192kHz. I also listened to internet radio, but for me that is not very important. My main target is to play gapless high resolution streams. My music files are stored in a Vortexbox as well as a Synology NAS and all the M50 needs is a network share with the files on it. For reviewing I can also play music from the M52’s library. My Logitech Squeezebox Touch is side by side with the M50, both connected with Stereovox 75 Ohm cable to my Esoteric D-07 DAC which I have programmed for PCM to DSD conversion. The Ethernet cable between a Cisco switch and the M50 is ordinary CAT5. It cannot make any difference says my brain, I am a network expert and we transport gigabytes of data over these kind of cables. But a week later I try a CAT7+ cable from Supra and although I do not understand why, again the total sound quality improves. This one meter piece of cable works like changing from an ordinary power cord to a good one. I now use CAT7+ between my Vortexbox, NAS and switches. But not in between switches, I don’t want to rebuild the house!
Briefly the rest of the system: Audia Flight Strumento No. 1 preamp and Audia Flight 50 power amp, PMC fact.8 loudspeakers, Yter balanced interconnects, Crystal Cable power and loudspeaker cables, Kemp Elektroniks mains filters, Quadraspire audio rack and Acoustic Systems resonators on the walls.



NAD M50 power supply

Sound quality
Let me start the listening experience with the Logitech Squeezebox Touch, which I have used without any complaints for over a year. Sadly no longer in production, it was very good for its money, until the M50 arrived. Suddenly it Touch didn’t sound so good, the stereo image is smaller, it has a more sterile sound and is a touch metallic and sometimes voices seem to hiss. This was never very obvious but is easy to hear in direct comparison. There has always been a rather large gap between digital and analogue in system, I could never close the gap, not even with expensive SACD players. I could live with it but if I really wanted to listen to the best sound I played vinyl. That is until the M50 made an entrance.
The improvements that the M50 delivered over the Touch were a far larger stereo stage (width, depth and height), a more natural sound that’s a lot closer to analogue and high frequency digital artefacts disappeared. As a CD transport the M50 equals my Cyrus XT Se with PSX-R. I replaced the Stereovox cable with an Apogee Wide-Eye XLR and the CAT7+ came in and that was the way I listened for the next few weeks. I will try to describe roughly how music is played in my room.
Arvo Pärt is a composer from Estonia who wrote Spiegel Im Spiegel for piano and violin. It is the loneliest piece of music that ever came my way, but so, so beautiful. I cannot remember another moment a piano was more lifelike and natural, or a violin came in from a deeper and quieter background. Unless I listen to my record player that is. The same piece of music is played on the next track with a cello instead of a violin. It’s even more emotional, cello up front, piano more to the wall of the studio, with a light echo added. The distance between the cello and the piano can almost be measured with a ruler. I ripped this music myself from a CD to the M52 and copied the files to my Vortexbox. The next piece of music is played by the Combattimento Consort Amsterdam, a composition from Jan Dismas Zelenka. The Bourreé makes me happy again, just like the Capriccio later on, it’s placed a few meters from the listener, but still close enough to catch the intimate atmosphere. I do not feel lonely any longer, the feeling I got from Arvo Pärt is gone by now. Because the M50 can handle high sample rates I played some 88.2 kHz sample rate Mozart from the Scottish Chamber Orchestra. This immediately shows the limitations of CD sample rates, the 24-bit depth and the higher sample rate improve the impact of the music, open up a larger soundstage, make it easier on the ear and closer to the original. Like playing a record but without tracking distortion, noise, ticks and pops. This music shows how well digital streaming works. The Adagio is very pure, I love the tenderness of the violin and I get lost in the music. These are the moments you realise how good the M50 is compared to a Logitech solution. The difference was obvious with lower sample rates, this magnifies them.


The album Xiomara by Xiomara Laugart is a 24/96 download from HDTracks and a textbook example of a recording for space, placement, openness and distance between instruments. The loudspeakers totally disappear and you look into the mastering room of a decent studio. Is this the moment I have waited for for so long? Where the supremacy of vinyl finally comes to an end? Yes, it took 30 years but here we are. We can move up even more to 24/192 with Linda Ronstadt who sings I’ve Got A Crush On You from her album What’s New. Sorry Linda, you are well past ‘new’ but your voice is not. Although I get the feeling that sound quality was more important on the CD than musicality for the recording guys. Take for instance Barb Jungr on 96kHz and let her sing Always On My Mind, that is the way to use high resolution. Nevertheless, the conclusion is clear, the NAD M50 is the winner when streaming with my own DAC, no matter what the format. I never got these results with Linn or Naim to name a few, let alone with Logitech (always Ethernet in, digital out). Not even with dedicated music servers, directly connected with USB or analogue out. The NAD M50 surpasses the whole bunch.
It seemed unimaginable that NAD’s mother company would spend a fortune to only develop the M50/M51/M52, complete with software and app. I expected, just like with the M2 amplifier, a more affordable set up (like the C390DD). However NAD is planning a complete new brand to win a large part of the market from companies like Sonos, Logitech and a lot of others. This new brand will offer active speakers with streaming capability or just streamers with amps in a box. I have one right in front of me, an attractive module that connects over Ethernet or wi-fi just the way the M50 does, with the same app (but another name in the logo), playing music from the same sources. Inside the box is an amplifier just like in the M2 or C390DD, only smaller. Actually it is a D/A converter with enough power to drive my PMC Twenty.23 speakers, or a set of monitors combined with a subwoofer for that matter. Connection is very easy, power cord and speaker cables, add the unit to your router table, fill in the network shares and play your music. Do not expect high end reproduction, but do expect a very good sound, a very easy user interface and a well-designed box. This way NAD is able to fully service its high end customers, while the new brand* can focus on everyone else looking for a decent sound anywhere at home, without the need for a dozen boxes. It is very easy to combine the two worlds I experienced.


M50 Digital Music Player Rear
NAD M50 rear panel

For those readers who look at the conclusion first I will present the results of the M50 compared to other streaming products and/or to analogue. I can be very brief about the M50. Anyone using a Logitech or any other comparable digital music player that’s looking for something better needs an M50. When playing decent ripped files it will surpass many CD players, even top quality SACD players. Finally music streaming over Ethernet is comparable with high end analogue equipment, but a lot easier to handle, without noise and without damage over time. A NAD M50 combined with a NAS drive or M52 means you can your CD collection in the attic for good, you need never look back to the silver disc. Those not willing to pay so much should visit a dealer later this year for the new mystery brand, ask for loudspeakers with wi-fi to play your music wherever you like, or modules that replace a normal stereo system to play music from central storage over existing loudspeakers. Use your tablet to control your personal jukebox. But to get back to the M50, it is not only an extremely good digital music player, I would say it is a major step for the audiophile mankind.

* Rene is sworn to secrecy on this but a bit of research should get you on the right track.

This translated review was previously printed in the Dutch magazine Music Emotion


Inputs: USB 2.0 Device (Type B) for NAD M52 USB Storage, Front and Rear USB 2.0 Type A for playback via USB Stick, Hard Drive IR Input 12V Trigger In
Outputs: Coaxial & Optical S/PDIF, HDMI 1.4 (Audio only), AES/EBU
12V Trigger Out
IR Out
Network connectivity: WiFi 802.11n/g 2.4G, Ethernet 10/100Mbs, RS232
Sample Rate: 32kHz to 192kHz, 16/24 bit
Audio Formats: FLAC, WMA, WAV, OGG Vorbis, AIFF, ALAC, MP3
USB File Systems: FAT 32, Linux EXT
Standby power: <0.5W
Unit Dimensions (WxHxD): 435 x 115 x 305mm, 17 1/8 x 4 5/8 x 12 1/8 inches (including feet, extended buttons and rear panel terminals)
Net weight: 8.1kg (17.8lbs)

USB 2.0: Mass Storage Mode
Number of Drives: 3
Capacity: 2 Terabyte
Configuration: RAID 5
Standby Power: <0.5W
Idle Power: 20W
Unit Dimensions (WxHxD): 440 x 295 x 78mm, 17 5/16 x 11 5/8 x 3 1/16 inches
Net Weight: 8.12kg (17.9lb)

Price when tested:
M50 £2,000
M52 £2,200
Manufacturer Details:






Streamer & server


René van Es

Distributor Details:

Sevenoaks Sound & Vision
T 01732 775635


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