Any comments on the new audio formats?

[BGHD]

I posted a thread in the "cool products" forum and it made me wonder how much better does the TrueHD, DD+, DTS-HD, etc, sound. Anyone have an opinion on this? What equipment do you have?

[Fantom]

It seems you posted this way before anyone had really heard these or knew anything about them. These formats are fairly common now in high-def players and receivers.

I have a PS3 for blu-ray, which decodes TrueHD on board, and might soon handle DTS-HD, or at least I hope.

I also have an Onkyo TX-SR705, which can accept and decode these formats from bitstream (PS3 cannot currently output them as bitstream though).

The best part about these 2 codecs (TrueHD and DTS-HD:MA) is that they are lossless compression. Basically you get all the quality of PCM, but at about half the size.

The real gain is when 24-bit audio is used. Standard CD quality audio is 16-bit per sample per channel. 24-bit is a noticable improvement (at least with my trusty Sierra-1s).

Some movies, such as Spider-man 3, have a 16-bit PCM track and then a 24-bit TrueHD track. The TrueHD track in this case is better. It is about 3/4 the size of the PCM track on disc, but decodes to 1.5x the information.

With 24-bit tracks, the sound can be less compressed (in terms of dynamics and range, not file size compression), offering a more dynamic soundtrack that is closer to that of a theater. Many people equate volume to quality, and will prefer more compressed audio to more dynamic audio. For this reason, many have claimed that the PCM track on Spider-man 3 sounds better to them than the TrueHD track. Especially since if you switch between them without adjusting volume, the TrueHD track will sound quieter. As long as you have an amp that's up to going a little louder, the more dynamic track is obviously the way to go.

Other movies, such as Ratatouille, have just gone with making the PCM track 24-bit. Yes, this can be done as well.

You might ask why put an uncompressed PCM track on the disc rather than a TrueHD track at half the size. Simple. All blu-ray players are not required to support TrueHD. With the increase in recievers supporting hdmi 1.3 and TrueHD decoding, it is easy for the players to just output the bitstream, but this is still not required.

[BGHD]

Great info. I've since bought a Toshiba HD-DVD player outputting PCM via HDMI to my receiver, but had to take down my system before I could really test some movies w/ TrueHD tracks. Can't wait to have things up and running again.