How To Play High Definition Music Downloads
HD And CD+ Audio Playback for Hi-Fi Stereo Systems
Oct 14, 2009
A quarter of a century has passed since Philips and Sony defined the sampling rate and bit depth of the compact disc. Since then the world has seen computer hard drive storage increase by more than ten thousand times.
There have been some attempts to improve the CD technical parameters, particularly for lovers of classical music. Disc based solutions like HD-Audio and SACD were not as successful as they should have been, but download services have been a great success, and high-definition download services are appearing to serve a niche audiophile market.
Rock and pop fans have had a raw deal, as the emphasis on background listening and the convenience of car and Ipod listening means that mastering has chased loudness rather than fidelity, but some companies are beginning to cater to the non-classical market too.
High Definition Signal Formats
Though one or two companies persist in using digital rights management (DRM) most recognise that there is not enough standardisation in the market to get away with this, and offer unencrypted losslessly compressed FLAC files at 96kHz or 88.2kHz sampling rate and 16 or 24 bit resolution, with 96kHz being the most common format. DRM files are only compatible with hardware supporting the version of DRM - this will limit the player to be either a computer or something like an iPod.
As a customer it is best to prefer non-DRM files, which can be played on a variety of hardware. The obvious choice of hardware is the computer, but that is not usually the best choice for sound quality.
Reasons Why Playing Hi-Definitions Music on a Computer May Not Realise High Definition Sound Quality
The simplest way of playing back a high-resolution file is to play it out on a computer such as the one used to download it. However, this is unlikely to be the best way, for a number of reasons.
- Computers are audibly noisy - fans and hard disks disturb the quiet passages
- Computers are electrically noisy - the myriad of signals in the computer can interfere with the sound card and inject noise into the typically unbalanced signal cables of a domestic audio system. These can be audible as faint tones and whines in quiet passages.
- Cheap sound cards often use sample rate converters to resample signals to the common mixing bus frequency, typically 48kHz
Most of these issues can be addressed by using a dedicated quality USB or Firewire sound card. Alternatively a SPDIF digital audio interface working to a dedicated audio DAC in a hi-fi system. Some of the electrical noise issues can be solved by using Toslink optical digital interconnects.
Alternative High-Definition Music Playback Sources Are Dedicated Hi-Fi Components
Listeners that have one main hi-fi system can use a hard disk music player like the Naim HDX, which can play back music stored on the internal hard disk. The machine can be placed on a computer network for loading but does not have to be network connected to run. Other companies make hard disk CD jukebox products like the Sony Giga Juke, but it is worth confirming they support HD natively.
Alternatively, most dedicated audio streaming solutions can play back high definition files natively. Such systems include Meridian Sooloos, Logitech Squeezebox and Transporter, Sonus and Linn Digital Stream. These systems can often stream over WiFi and pick up the files from the computer used to buy them from the high-definition music download suppliers, and they can usually support multiple players in the home too. However ,they do involve a little more setting up than standalone hard disk players, and the system.
High Definition Audio Related Articles
Readers may be interested in where to buy HD audio downloads, Logitech SB3 Classic streaming player and the Naim Audio DAC
 |
 |
