LPCM vs. TrueHD

[NutsAboutPS3]

TrueHD is lossless, so will be identical to the uncompressed sound track it was made from. The only way it can sound different to an uncompressed track is if it wasn't made from that uncompressed track, i.e. they differ in some way other than the fact that one is uncompressed and one is TrueHD:
http://www.dolby.com/consumer/technology/trueHD.html

In this respect it's just like using pkzip, and nobody ever complains that their data files just don't seem the same after they've been compressed and extracted from a zip file.

The only way to do a fair comparison is to take an uncompressed track from a Blu-ray disc, encode it to TrueHD, then burn both tracks back to disc and listen to them. This is the only way you can know that you're listening to the same audio track.