Finding solutions

One of the fun bits of this job is inventing protocols to unambiguously determine different aspects of performance. While this is now largely a thing of the past (since most Blu-ray players now feature full audio decoding for all codecs), working out whether a player really did decode DTS-HD Master Audio was difficult to begin with. When I did work out a solution, I recorded the procedure in an email. This is it, slightly edited for clarity:

Confirming the ability of different players to decode DTS-HD Master Audio has always been pretty difficult since, as you know, a player that won’t decode DTS-HD Master Audio instead decodes its standard DTS core. I’m not sure about you, but I wouldn’t like to judge this just by listening to a track fed via bitstream and decoded by the receiver, and then by the player and converted to PCM. Such subjective assessments can easily lead one astray.

So for the past few months I’ve been trying to get ahold of a disc which might prove more definitive. Finally, during the week, I received the ‘2008 High Definition Audio Demonstration Disc‘ in Blu-ray from DTS. This has a number of tracks which help me work out decoding capabilities.

First I play them back using bitstream output and examined the signal information reported by a Yamaha receiver. This confirms that the tracks were appropriately labelled on the disc. Then I switched the player to PCM output.

If  the 7.1 channel DTS-HD tracks with either 48 or 96kHz sampling are all decoded to 5.1 channels at 48kHz, I can conclude that the unit is only decoding the standard DTS core rather than the full Master Audio code.

Likewise, if the the 96kHz 5.0 channel tracks are decoded to 48kHz 5.0 channel PCM.

Meanwhile, I have a spare copy of The Fifth Element on Blu-ray. This is the Madman Entertainment’s version. The video encoding is identical to the previous Sony version released in Australia, but it has some extras. No box or slick. First to ask for it in comments can have it – postage to Australia only.