“Digital Music Players”
These all-in-one units have integrated storage and built-in DACs. The Bluesound Vault fits nicely into this category as it includes the server, 2TBs of internal storage and a digital to analogue converter. Some all-in-one models even have digital inputs so that they may be used as dedicated DACs. The storage typically found in DMPs is less sophisticated than the RAID 5 array found in the NAD M52. It often consists of a single hard drive without any built-in redundancy. In order to protect your music collection, it should be backed up to a secondary external location such as a USB hard drive, a computer or NAS. Some all-in-one DMPs go a step further and even offer built-in amplification. Perfect examples of this are Naim Audio’s Uniti range of players as well as various products from Cocktail Audio.
The Sonos wired / wireless HiFi system is perhaps the most popular DMP in the world. However, it doesn’t fall neatly into either product category. It consists of Sonos speakers and a device like a smartphone or a tablet running the Sonos App. Unlike traditional passive units, Sonos speakers are active. They contain a built-in music streamer, DAC, amplifier and the speaker itself. When you play music with a Sonos system, the app wirelessly streams the content to the speakers. These in turn, receive, convert, amplify and play. It makes for a wonderfully clean and efficient setup.
If you already have an amplifier and speakers, the Sonos Connect will serve as a wired or wireless receiver and DAC. Just connect the analogue outputs to your amplifier and you’re ready to go. The Connect has a built-in volume control so you don’t even need a preamp. If you have speakers but no amplifier, the Connect:Amp adds an internal amplifier to the mix.
The Sonos app is a wonderful piece of software. It’s very intuitive and user friendly. It also makes it really easy to setup a multi-room system. Sonos offers three different speaker models and even a wireless subwoofer. With its very reasonable pricing and first rate industrial design, it’s easy to see why Sonos has become so popular. The only downsides are that the Sonos system doesn’t offer any onboard storage, nor is it capable of decoding high resolution formats like FLAC 24 bit/192 KHz.
A word about DACs
24 bit/192 KHz audio files may be the highest resolution you’ve come across but believe it or not, it doesn’t stop there. Some DACs can process 32bit/384 KHz files. Even sampling rates as high as 24.576 MHz are available. Insane? Perhaps, but it is out there. Octuple-rate Direct Stream Digital (DSD) recording capabilities are found in some professional gear. The consumer electronics industry won’t have to worry about this anytime soon but stopping at 192 KHz seems premature. Super Audio CD (SACD) uses the DSD encoding scheme. If you wish to decode stereo DSD files, a 5.6 MHz DSD compliant DAC would be a great idea. The Marantz NA8005 boasts this capability. I cannot understate the importance of your DAC. It will be the single largest contributor to your DMP’s sound quality so you should definitely purchase the best one your pocket book can afford.
USB DACs are essentially external sound cards for a computer. With a traditional internal sound card, the audio bit stream travels across the PCI-E bus and into the sound card’s DAC chip producing an analogue output. With a USB DAC, the bit stream is transferred to the sound card via the USB port rather than the PCI-E bus. However, early versions of USB were simply not designed for streaming audio so there were certain limitations. Later generations solved these issues. Make sure that the model you’re interested in supports the Asynchronous USB Audio Class 2 standard. This standard supports 24 bit resolution and sampling rates up to 192 KHz. The earlier Class 1.1 standard was limited to 24 bits and 96 KHz. The NAD M51 DAC is a great example of a model supporting the USB Audio Class 2 standard. You should also make sure that the DAC supports all the file formats that you’re interested in decoding including DSD.