What? A Clockwork Orange, Eyes Wide Shut, and 2001 24-bit PCM?

[yoshi_5]

Originally Posted by TheHighRoller

But I remember stumbling on a site that talked about DTS and LPCM, and there they said that LPCM was always 24-Bit.

I saw this on another site a few days ago, I take no credit for the information, just found it very informative.

Cut&Paste Below:

All modern films are mastered with 24/48 audio. Employees at these mastering facilities, as well as the individuals doing the theatrical mixes, have said as much on this forum. Even paidgeek has said as much over on the Industry Insiders thread. [Older movies, without a recent audio remaster, are 16/48.]

Due to the high bandwidth and space requirements of uncompressed audio (LPCM), most studios downconvert 24/48 master audio to lower 16/48 fidelity for use on Blu-ray disk. Only a small number of Blu-ray disks with LPCM feature master quality audio; more than 85% of all releases with LPCM feature inferior 16-bit audio. Paidgeek -- the representative from Sony Home Video -- has said several times over in the HDTV Software Media forum that Sony intends to stick with 24-bit -> 16-bit downconversion on LPCM releases for the forseeable future, due to bandwidth constraints.

Note Sony Home Video recently decided to make more use of TrueHD on future titles to deliver the full 20-bit / 24-bit fidelity of the master.

Rather than downgrade the 24/48 master audio to lower 16/48 fidelity, some studios (FOX) have chosen to losslessly pack or "zip" these audio masters with DTS-HD MA or Dolby TrueHD. Once unpacked or "unzipped" by a player or future HDMI 1.3 receiver, the resulting output is a 24/48 LPCM track that is bit-for-bit identical to the original studio master.

LPCM
2 hours @ 5.1 16/48 LPCM = 4.14 Gbytes @ 4.6 Mbps (used on most Blu-ray titles with LPCM)
2 hours @ 7.1 16/48 LPCM = 5.52 Gbytes @ 6.13 Mbps
2 hours @ 5.1 24/48 LPCM = 6.21 Gbytes @ 6.9 Mbps (used on Disney Blu-ray titles with BD50 + AVC)
3 hours @ 5.1 24/48 LPCM = 9.32 Gbytes @ 6.9 Mbps
2 hours @ 7.1 24/48 LPCM = 8.28 Gbytes @ 9.2 Mbps
3 hours @ 7.1 24/48 LPCM = 12.42 Gbytes @ 9.2 Mbps
2 hours @ 7.1 24/96 LPCM = 16.56 Gbytes @ 18.4 Mbps
3 hours @ 7.1 24/96 LPCM = 24.84 Gbytes @ 18.4 Mbps