DVD-A vs SACD vs HDCD vs CD

[70sMac]

I hope that I'm on the correct board.

I just read a wiki article about DVD-Audio. I was trying to figure out if all DVD-A recordings offer 5.1 encoding, so that's my first question for the music board. Does DVD-A normally include 5.1?

Although the wiki article was a bit unclear about DVD-A and 5.1, it did contain some text that really caught my eye. In short, it stated that, according to "researchers," there was no discernible difference between DVD-A and SACD and, furthermore, that there's no discernible difference between the SACD and the CD audio formats!

You see, we purchased our first SACD-capable player about 18 months ago, the Sony X800M2. I subsequently discovered that we would need a DAC to use the X800M2 with our Mac MX130 Control Center. Well, we don't presently own a DAC, but we have been adding some SACD titles to our collection in hopes of someday enjoying them.

So...any thoughts on the DVD-A, SACD, HDCD and/or CD formats and, most importantly, how they compare to one another would be greatly appreciated.

By the way, we do own an HDCD capable player -- and I certainly hear a difference between those discs and the normal CD discs in our collection.

Thank you very much for your time...