Some information based on searches:
Dolby TrueHD is Dolby’s next-generation lossless technology developed for high-definition disc-based media. Dolby TrueHD delivers tantalizing sound that is bit-for-bit identical to the studio master, unlocking the true high-definition entertainment experience on next-generation discs
Features
-100 percent lossless coding technology.
-Up to 18 Mbps bit rate.
-Supports up to eight full-range channels of 24-bit/96 kHz audio
The new audio CODECs are lossless which simply means without loss, or identical to the original. The three lossless CODECs supported by both formats are LPCM(not really a codec), Dolby TrueHD and DTS HD MA. At this point the question should be, if they are lossless than what is the difference? The difference for the most part is the number of bits. Both Dolby TrueHD and DTS HD use far less bits than LPCM, this leaves more space on the disc for other features.
So how many bits are we talking about here. As an example a 2 hour movie with a 16/24, 5.1 sound track requires 4.14 GB with LPCM vs 1.26 GB for either TrueHD or DTS HD.
LPCM is not being used at higher than 48kHz sampling rate because of the datarate/storage that would require.
Dolby TrueHD definitely supports higher sampling rates than 48k
Uncompressed Linear PCM just like CD Audio. DTS-HD MA and TrueHD are lossless compression schemes aka codecs. DTS-HD (without the "MA") is a very high bitrate, yet LOSSY codec. DTS-HD Master Audio (or "MA" as most of us call it) is lossless.
So I ask this question would you rather listen to DTS-HD MA 24bit/48kHz since the disk has enough space for it or a "downres" the 24-bit, 48kHz LPCM master track to 16-bit, 48kHz LPCM?
I dont know the answer and I dont know if my ears can even tell.
LPCM offers nothing over TrueHD except it takes about about 2-3x the space. Either your player or receiver needs to support TrueHD and DTS-MA. But if the HD movie is mastered theoretically up to 192/24 (I don't think anything is done this high) you can fit a DD TrueHD and DTS-MA into the disks. Theres not enough room to have LPCM 192/24 in todays disks. We might need to wait for the quad sided Blue Ray disk on the PS5
Please correct any assumptions above.
