The concept behind SACD is "Supposed" be a better emulation of an analog signal. Instead of a fixed digital word length (16 bit, 24 bit etc) SACD uses "Direct Stream Digital", a high bit rate of 2.822MHZ streaming data format of 1's and zero's. This streaming information uses very little processing to emulate the original analog signal. DVD-A uses 24 bit at up to 96kHz and up to 6 (5.1) channels. Typical audio CD uses 16 bit resolution. Each bit is double the previous so a 17bit signal has twice the resolution of a 16 bit signal. 18 bit has 4 times 16 bit, 19 has 8 times. That said, 24 bit isn't 50% higher resolution, it's 256 times the resolution. Think of a jaggy looking digital picture compared to a nice smooth one. You can still tell it's a picture of a tree on the jaggy one, but on the smooth one, you can see the texture of the leaves and other subtleties. Same goes for digital audio. It sounds like an acoustic guitar, but the higher resolution shows all the nuances that make us spend lots of money on our home theatre systems!

Which one is better? Couldn't tell you. Like others on this list, I bought a player that plays both, although the hard core enthusiasts will cry that unless you have a true decoder for each, which is typically separate players, your sacrificing the quality of one or the other.

From a recording perspective, there are very few studios that have the capability to record native SACD format so may of the disks are recording in something closer to DVD-A format to begin with unless they were recording strictly analog. Not a lot of that happening any more.