CurtPalme.com Home Theater Forum

[WanMan]

After watching about a dozen Blu-ray based movies in the theater I can say that I truly do not like DD True HD audio, and that I much prefer the DTS-HD Master Audio. While I suppose I should always leave the observations open for alteration (i.e. Denon processing), and that individual content is not always created equally, I have listened to enough of both to form this early conclusion.

For some reason the DD True HD encoding seems flat on the front channels (LCR) and LFE, but DTS HD MA seems to be more flat on the surround channels. But there is nothing more annoying in audio than feeling like the characters in front of me on the screen are being listened to with someone in front of me (like I'm in the second, unelevated row).

Anyone else observe this? It really stood out on the Iron Man feature we watched last night--and supposedly listened to.

[WanMan]

Watched Across the Universe, and it, too, seemed flat. Is True HD just ... flat?

[dturco]

Nah, True HD is anything but flat. You have something set wrong. True HD only works over HDMI OR the analog outputs. If you are using a toslink or coax cable it downmixes it to DD or lower.

Also you might have to select playback as default to True HDa DTS master in your pre pro and blu-ray player for signal continuity.

[ecrabb]

Is there still a difference between sub levels in TrueHD and DTS-MA like there used to be between AC-3 and DTS? That would account for it sounding "flatter" if the sub level was lower in one.

Wan... How did you end up running your LCR's... "Small" or "Large"? How are the speakers set up?

TrueHD and DTS-MA both sound excellent in my setup.

SC

[greg_mitch]

Is phantom center possible when playing a TrueHD or DTSHD-MA track?

[WanMan]

The speakers and sub are setup using the Audyssey calibration with some post-calibration changes that included LCR being set to Small, the center booted by 1-2dB, and I forget what I have the sub setup with.

So far, DD<DD THD<DTS<DTS HDMA in terms of one sounding less amicable than the other from the front stage. I am never unimpressed with DTS HDMA. I still hold something might be up, though, with Dolby.

BTW, I am a noice of noices when it comes to knowing the technical difference between Dolby and DTS. All I know is that it takes a scene with an act from god for me to be convinced a sub exists in Dolby. Sure, I exaggerate because I have walked up to the sub and felt the cone to be sure it was 'working', but in DTS I don't have to do this at all.

[ChrisWiggles]

AFAIK they should be fully identical if they come from the same source. Both are lossless formats. There is no reason that there should be any difference unless there is a setup/system problem, or a soundtrack authoring problem. Handled correctly, they should be 1:1 literally bit-for-bit identical.

I've watched a lot of BD movies, and I've never found any discernible issues with DD THD soundtracks. Though I do find it interestind that DTS-HD seems to be more common, at least on the discs I rent (though many are from Criterion, so it may just be my limited viewing since I don't watch many blockbusters from a larger variety of studios and authoring houses).

[WanMan]

Hmm, then let me investigate this as a AVR problem. Maybe there is a Dolby post-processing that got enabled and I am just ignorant of it.

[Ron W]

Just like most everyone else, I too, have watched and listened to several movies, especially those of the action genre which tend to have more dynamic and deep bass and really hear no discernible difference between the two lossless formats and realistically, there shouldn`t be any. The LFE channel that was prevalent in Dolby Digital and DTS did have slight differences in measuring and calibrating volume but this channel no longer exists in True HD and DTSMA soundtracks. What you hear is what has been done in the post-mixing process in the movie and generally whatever differences that "may" be heard is in that mix and not related to any perceived limitations of either surround sound process.

What is somewhat different is that Blu-Ray discs will have one or other of the lossless formats in multi-channel audio but unlike many DVD discs, no longer both so you really can`t compare the two anyway. The DTS soundtracks generally were about 3-4 db louder than DD on DVD discs, so this is where this perceived notion of DTS superiority came in to play. Once you equalized the volume levels and listened generally the soundtracks were pretty similar.

I have noticed that up until now, DTS MA is the only one that has produced a few 7.1 soundtracks whereas with TruHD, although they may exist, I have yet to see any movies that are mixed in anything else but 5.1.

[WanMan]

When I increase the master volume on the AVR it is usually ~6dB or more and the result still isn't as good as DTS HDMA.

[ecrabb]

OK, that's weird, Wan... What's your BD player, your AVR... and I assume they're connected via HDMI, right?

As others have said, they're really shouldn't be any discernible difference between the two.

When you say it's "flat" across the mains when you're listening to TrueHD, give me some more detail... Are we talking about lack of bass, lack of treble, what?

SC

[kschmit2]

Check if your AVR has a Dynamic Range control setting, and change that to the setting that willl not alter the dynamic range.

Don't know what that setting would be on your AVR, since you haven't posted what model it is

Kai

[Ron W]

[ChrisWiggles]

What is your specific setup? (what gear and how is it connected?)

And what title are you comparing?

Because mathematically speaking, they ARE lossless formats. They will be 100% bit-for-bit identical to the uncompressed studio master in either case. Because I'm not doubting that you're hearing what you're hearing, but if it is so then there is an addressable reason for that which necessarily has to do with the particular gear and its setup.

There are a lot of ways to screw up getting lossless high-res audio from BD depending on what the gear is and how it is set up. You may just be listening to down-ressed lossy DD/DTS for instance, which without any detailed info is my likeliest hunch.

[WanMan]

Early on I had trouble with the Sony BX1 (S350 relabeled for Costco) not outputting bitstream and the Denon AVR-3311CI was seeing the result as simple Multichannel In. Once I figured out the cause, I started seeing DTS HD Master Audio and Dolby Digital True HD show up on the AVR display.

Again, I did an initial setup using the internal Audyssey calibration, but then adjusted for CC, crossover on subwoofer, etc. and the end result driven into the v2 Paradigm Studio 100's ADP Surrounds and CC. I am not yet using the Emotive XPA-5 in the theater as the equipment is in a temporary location.

I am happy with the DTS HDMA results, but not the DD THD. Titles include Band of Brothers, The Pacific, The Dark Knight, Star Trek (reboot), Iron Man, Across the Universe, Doctor Who Series 5, Sherlock (2010 BBC), Kick-Ass, and several other titles that I'm not thinking about this morning (I'll get them for you).

I would think if the AVR is doing something to reduce the codec that it would advertise as such, but then again who knows.

[dturco]

Turn the Audyessy mode off.

Wan have you ever listened to anything in the new room to compare this too? You may be hearing nulls in the frequency responses that are room created. It may take moving the sub from where you have it, or want it, to somewhere will it isn't operating in a null mode or like being out of phase. Or even just that, you may have to adjust phase on the sub.

Room acoustic DO make a difference. So does using a computer to address the room modes, IE: the Audyessy. Algorithms do not make good adjustments sometimes.

[kschmit2]

Wan,

did you try to turn off DRC? (should be page 73 of your manual)

[WanMan]

Hmm, I hadn't considered DRC (didn't realize it existed) in TrueHD mode. Manual doesn't say what the default is. I just shut the projector off, but I will check to see if this is enabled in any way.

BTW, the Audyssey equivalent of DRC is unavailable once I altered the Audyssey Auto Setup values. Audyssey was only used to prevent me from hunting down the sound meter and manually setting speaker distance:level. I'm not using it beyond the lazy money setup (e.g. not Audyssey processing).

I understand environment can impact the net results, but should I consider DTS-HDMA to be the sole beneficiary and all other processing modes being burdened? That'd be funny.

[benareeno]

I didn't think the 350 could bitstream HD audio...

and if that is the case, you would not be getting either TruHD or DTSHDma....you would be getting downsamples of each, with the DTSHDma downsampling being very close to the lossless track and the TruHd being about half bitrate...might explain your conundrum.

[WanMan]

Already walked that path. Before I got bitstreaming enabled on the player I would only get Multichannel In on the Denon. Once bitstreaming was enabled, I finally got DTS Master Audio and Dolby TrueHD.

Honestly, if there were no differences between Dolby TrueHD and DTS Master Audio then why would a studio use one over the other?