AC3, MLP, what really happens to the audio with AC3 as far as quality?

[808st8]

I'm aware that AC3 is a Dolby Digtal 5.1 form of compression, so what exactly happens to the audio as far as how it sounds from the studio to the home theater? I know that MLP (Meridian Lossless Packaging) has no loss of quality, since it compresses the audiuo then completely reopens it, but the gear for doing MLP encoding is pretty expensive at this time. By getting DVD Studio Pro with Apack, one can make surround sound music in a pinch if you know what your're doing. I can hear a difference between my SACD's and DVD-A's for sure, I'm just curious how much compression is going on with AC3. Minor, major?

Thanks guys,

808st8
Austin, TX

[Bob Olhsson]

I'm pretty sure the bit rate can be adjusted. I attended the Dolby Digital introduction in San Francisco several years back. The inventor flat-out told us "it's great for film but you probably wouldn't want to do this to music."

[808st8]

Thanks for the reply. I've been just practicing with music in surround sound using ProTools, Final Cut Pro, and DVD Studio Pro. It sounds so so with AC3. No way near how good it sounds in the studio. I'm pretty much self taught on the 5.1 thing, so I've left the bit rate at the default and accepted the way it's turned out. One person told me to leave it at 4.5. Who knows. Do I just keep pushing it up until my DVD player won't read it? Sounds kind of like buffer size adjustments for soft synths. Back and forth again and again. Sure would be nice if it could sense the optimum level for your system. DVD-Audio would be oh so nice. Until then.
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808st8
Austin, TX

[fishtop_records]

AC3 does a real number on serious audio.
It was invented/standardized long before
anyone wanted high res, wide audio.

MLP was invented because the DVD-A folks
couldn't get the bandwidth off of the DVD to have
five 96/24 channels. So rather than doing a lame
low/narrow spec, the folks at Meridian showed them
how to easily get a 2 to 1 compression, lossless.