Super-audio CD and DVD-audio - High-definition music explained

High-definition TV might be grabbing all the headlines at the moment, but back in 2000 audio when through its own high-definition upgrade.

That’s when two new formats for music first saw the light of day. The first is called Super Audio CD (SACD) and was jointly developed by Philips and Sony. As its name suggests it’s an upgrade of the standard audio CD, but it offers much higher sound quality.

Around the same time a second format was also introduced. It’s known as DVD-Audio and was developed by the DVD-Forum, a consortium of large companies that includes Pioneer and Panasonic. As you would expect it’s based on existing DVD technology, but it also offers a significant leap in audio quality over the traditional CD.

Snap without crackle
To understand how these formats improve on the existing technology used in audio CDs you need to know a little bit about digital audio. Sound stored in digital format is captured as a series of snap shots that are then played back rapidly to recreate the original audio.

It’s a bit like how movement is captured on film. A 35mm film looks much sharper than a 16mm film because each frame contains more detail. Similarly, whereas CDs store audio with 16bits of data, DVD-Audio used 24bits of data and so each snapshot contains more information.

With film, the high the number of frames shown per second, the more fluid the onscreen movement looks. With audio the frames per second correspond to the sampling rate. DVD-Audio use a higher sampling rate of between 96KHz and 192KHz as opposed to the 44.1KHz used on a CD. SACD offers a similar leap in sound quality to DVD-Audio, but uses a new method of recording and storing digital audio called direct stream digital.

The upshot of all this is that the new formats hold significantly more information about the audio they contain than a traditional CD and so both SACD and DVD-Audio discs sound sharper, more detailed and more natural than a CD.

There are arguments over whether SACDs sound better than DVD-Audio discs, with many people claiming that SACDs have the edge. In reality the differences are minuscule and even audiophiles would be hard pushed to tell one format from another.

Immersed in sound
Another big advantage these formats have over CDs is that they support surround sound. Many classic albums have already been re-mastered in surround sound specifically to take advantage of this feature. They include Jeff Wayne’s War of the Worlds, Pet Sounds by The Beach Boys and Yoshimi Battles the Pink Robots by the Flaming Lips.

Like this story? Spread the news by clicking below:

 del.icio.us     Digg this     reddit!