lolz...interested in tryin out these ppl sound system?
you will hear the differences then

In fact, on BD, the sound is more obvious upgrade than the video, at least to me.

Well, to each their own.

Both DVD and BD tested using PS3

For this next portion of the test, I listened to a variety of material with the player both set to bitstream mode with decoding done in player and PCM mode with decoding being done in player. However, I chose one title to focus in close on and this time the title was the first 10 minutes of Terminator 2: Judgment Day HD DVD (UK Edition). The title has a nice DTS-HD Master Audio track and I was able to directly compare the lossy core vs. the lossless MA track.

Results? Well, I'd have to say that after intense comparison of the first 10 minutes of the film, they sounded mostly identical. I did know exactly what I was looking for as I am familiar with lossy compression techniques and I was able to hone in on a 5-second period of time where the MA track had more detail than the lossy track - prior to the first T1000 we see crushing a human skull, there are some ambient background noises; there is one particular tone of very high frequency that is reproduced for 5 seconds with slightly more detail on the MA track. However, since it is a weird ambient background noise there is no way anyone would tell the difference unless doing this specific type of A/B comparison, especially since you need to crank it to hear the difference on this 5-second passage. The music, dialogue, lasers, sound effects, etc, all sounded the same for the most part on both versions.

Seems like most people are noting the same thing I did in the OP - subtle increased high frequency response in certain scenes, especially with ambient noises. Nothing major, but a very subtle difference. I have to wonder if DTS is rolling off the HF response of the master at ~18khz on the core track, or if the perceptual encoder simply is deciding that those frequencies are ones we would not notice.

Also, the reports that the MA track is louder for some people is concerning to me. It makes me think DTS is pumping up the volume on the MA track to make people perceive it sounding better than the core track (people perceive louder as better). However, for Dynamic Range & quality purposes it probably would be better for the tracks to be quieter on average to give more headroom for extended dynamic range. Bottom line, they should both be the same volume.

So, based on others reports here it appears IMO DTS-HDMA is nice to have if you can use it, but I wouldn't lose sleep over it if your player/receiver isn't capable of it. The nuanced differences would likely go unnoticed unless you were doing direct A/B comparisons. Just goes to show how awesome standard DTS 1.5mbps actually is...

BIG different la ! can bet with 1 car 

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Added on November 20, 2008, 9:14 am
Klipsh 6.1 speakers.

bro aiman... maybe is the computer speaker?  taukeh lau wai mind to tell us ur Klipsch 6.1 model? PROMEDIA ULTRA type ar? 

The difference between lossy and lossless is like the difference between 192 Kbps MP3 and Audio CD. 

Neither Geoff nor I could hear any differences between the original PCM track and the TrueHD version, which should be the case, as they’re bit-for-bit identical. The lossless coding process is analogous to “zipping” computer files—it’s simply a function of more efficient packing that loses nothing along the way. With movies, TrueHD typically provides a two- or three-to-one bitrate reduction compared to the original PCM source.

Next, we compared the original to the Dolby Digital Plus version (that codec is found on numerous BD titles, and like TrueHD, is fully backward compatible with regular Dolby Digital decoders). Even on this extremely high-end system, we couldn’t hear any difference between the uncompressed and the compressed. Then, we compared the higher bitrate (640 kbps) that is found on the Dolby Digital tracks on Blu-rays to the original. "Golden Ears" Morrison was able to hear the difference, but I, and most others in the room with us, did not. Each of us had our turn in the prime listening chair, and couldn’t know the origin of the clips or their order of presentation.

The shocker came when we compared the lower 448 kbps Dolby Digital DVD bitrate to the original. There was an audible difference, but it was only ever-so-slightly noticeable (and this is with a high end audio system in an acoustically controlled environment that is so far beyond what typical home theater systems are capable of resolving). There was just the slightest decrease in presence with the DD version, not exactly a softening of the sound, but just a tad less ambience and a similarly small tightening of the front soundstage’s depth. Quite a remarkable result, I thought, and I was highly impressed with how much fidelity can be packed into such a relatively small amount of bitspace. If I was doing actual scoring, I would have awarded a 4.8 grade to the results I heard – the audible difference was that subtle.

The short clip chosen for us came from a DTS Blue Man Group recording, again using a spare, sparse selection for an easier and more revealing A/B comparison. Again, we found no differencebetween the uncompressed original track and the DTS-HD Master Audio version.

In addition to the DTS HD-Master Audio lossless codec, DTS also offers up a nearly lossless high bitrate format called DTS-HD High Resolution Audio, with up to four times the bitrate of their core DTS format, which we were able to audition via their Blu-ray demonstration disc. We then conducted A/B comparisons between the high resolution Blue Man Group PCM original soundtrack and the core DTS codec which has a Blu-ray and DVD bitrate of either 768 kbps or 1.5 Mb/s, in a somewhat similar but not totally blind fashion that we went through the week before.

It was déjà vu all over again. We switched back and forth between the original PCM master and the core DTS version, and here we found only the slightest, barely noticeable difference. From a frequency response standpoint, both versions were identical, with clearly delineated high frequency details, but the compressed version differed slightly only in barely noticeable presence —that sense of being “there”, with the original PCM track having just slightly greater overall richness. Whatever acoustic elements were removed in the code/decode process were clearly superfluous, at least for the most part, as the audible differences were so minor as to be almost unnoticeable—again, another testament to the capabilities of this highly refined codec.

So Subtle
What impressed, or perhaps surprised, me most about these tests was how good the base codecs actually are. The difference between the original audio and the basic Dolby Digital and DTS is a lot subtler than you’d expect, given the extreme amount of compression (around 10:1, a similar ratio to that of 128 kbps MP3).

That said, I could definitely pick out the difference between the lesser (or perhaps it’s more accurate to say “better”) compressed versions and the higher compressed versions. The difference is mostly in the presence, or ambience. The lossless, Dolby Digital Plus, and DTS-HD High Resolution compressed tracks were just a little more open and airy. I hate to say it, but they just sounded more realistic and transparent. The 448 kbps Dolby Digital and standard DTS tracks were less so, a little more closed off. Between the 640 kbps Dolby Digital and the uncompressed, the difference was even less noticeable. Enough so that most people, even those trained to listen for it, probably won’t be able to hear the difference.

The core DTS call is a little harder, as there wasn’t the same blind system in place to A/B as precisely as at Dolby. Results were similar, though.So by all means go for the new codecs, as they definitely sound better than what was on DVD. Uncompressed PCM, on the other hand, is just a waste of space (though compatible with everything).

If you’ve been listening at home and are sure you can hear a difference on your favorite discs, be wary. There is absolutely no way to tell that compressed and uncompressed tracks on any disc have anything to do with each other. They could come from different masters, they could be mixed differently, or any number of other variables that makes an in-home test, unfortunately, impossible. That said, trust your ears, and go with the one that sounds best to you. –Geoffrey Morrison