DTS-HD-MA Problem

Hello Community,

I got a new Onkyo AVR (my first AVR in general) and set all recommended settings on my ATV HD (not 4K).

I do understand the process of converting and passing PCM, due to Apple’s limitations a “simple” Bitstream is not possible for audio channels in DTS-HD-MA and Dolby True HD.

But I do not understand why there is absolutely no Bass when playing a movie which have DTS-HD-MA. On my Onkyo I set “direct” as audio profile, the manual says something like “playback audio as it comes from player” - that should exactly be what I want?!

When changing the profile to “Multichannel” there will be Bass but then the surround sound seems to be kind of modified…

Are there any information about that?
Is this because of Apple or because of Infuse?

Any information appreciated.

-remo

It is hard to say exactly. What is your setup and AVR model? Do you have ATV directly plugged into AVR?

From the old Onkyo I had this is what it said in manual for Multichannel:
“This mode is for use with PCM multichannel sources. The audio from the input source is output as-is, without surround sound processing.
-Input source: 5.1 ch, 7.1 ch”
And Direct:
“In this mode, audio from the input source is output as-is. For example, if a 2 ch source from a music CD is input, the output will be stereo, or if Dolby Digital signal is input, the sound field will be controlled in accordance with the number of channels present.
-Input source: MONO, STEREO, 5.1 ch, 7.1 ch”

Did you do Audyssey setup and make sure it knows there is a sub? It could be that the Bass you are hearing is actually through front speakers? You should see input source as Multich PCM.

Thank you for your very fast and nice reply.
I have an Onkyo TX-L50.
And the ATV is directly plugged into it via a new HDMI cable.

When choosing “Direct” I do have Bass when playing DD, AC3, DTS, … sources. Everything sounds fine. Bass disappears when playing DTS-HD-MA. I tried the setup (don’t know whether it’s names Audyssey). Even “simple” DTS sounds great. So the AVR knows the Sub.
DTS-HD-MA loses Bass entirely.

The AVR shows “Multi Channel PCM” on its display. But it does not extract the .1 for my 5.1 …

-remo

Okay just to clarify. When you say “I do have Bass when playing DD, AC3, DTS” does that mean through Infuse, which output is PCM, or from another source?

I think for each different input format you will need to set the appropriate listening mode. So as you change from 2.0 to 5.1 to 7.1 PCM source you will need to select Direct or Multi or something. Are they all consistent?

When I used direct with my old denon it bypasses the audio processing in the avr which caused weird playback. I had to use any other setting but this. I’d recommend contacting onkyo as this sounds like an AppleTV/avr issue.

We are talking about Infuse only.

Ok.
What would be “normal” behavior for playing DTS-HD-MA through Infuse on ATV?
Should any AVR always receive ie 5.1 as long as the movie has it embedded? Or are there any limitations in PCM?

Let’s say the AVR receives data but cannot find the .1 …?
Is that possible?

Well the receiver shouldn’t notice any difference between a 5.1 PCM from DTS vs DTS-HD MA when played through Infuse since Infuse already did the decoding. Are you sure the source you have does in fact have LFE channel. Have you tried several different DTS-HD MA movies? Can you verify with MediaInfo App too?

It happens with All of my DTS-HD-MA movies.
And media info says something like “DTS HD Master Audio 6 Channels @ 1500kbs” …

I’ve tested some other movies.
When pressing the info button on my remote while playing a movie, the info OSD always says “input multi channel pcm 5.1” no matter if DTS, AC3 or DTS-HD-MA … Bass is fine every time, except when playing DTS-HD-MA.

This happens only when selecting “direct” on my AVR. When selecting “Multichannel” there is Bass in any case, but then there’s kind of manipulated sound experience.

When in direct mode the receiver will only pass bass to subwoofer when if comes from the .1 LFE channel and not include any room correction processing to the signal. This means it will also ignore any crossover settings (when main and surround speakers get below a specific frequency 80Hz, they will pass audio to subwoofer even if not in LFE channel). In multichannel mode it will use your room correction settings such that other speakers will pass surround to subwoofer. Apparently some DTS sources don’t even use the .1 channel and all bass is mixed into the fronts and surround. If that is the case, direct would have no Subwoofer usage. And if you have tiny speakers you wouldn’t hear any bass from the rest.

I don’t think that there is a problem with infuse if a DTS works fine but MA doesn’t since it all comes out as PCM. I think it is probably the source material. Any problem with Dolby Digital vs TrueHD?

My suggestion is to use multichannel and verify the room correction settings to make sure they seem reasonable. That might also adjust overall volume so that you have to turn it up a bit. You could try running it again too. Probably don’t mess with distance but check levels and crossover.

I personally wouldn’t use direct for anything other than music where I want to listen in stereo but my speakers can handle some bass without a sub, too.

You could try downloading some surround demo files (Dolby and DTS) and test with those. Channel checks.

Thank you very much for your detailed reply.
I begin to understand now!

But:
„In multichannel mode it will use your room correction settings such that other speakers will pass surround to subwoofer.“

But doesn’t that mean that the Bass channel becomes modified and is not a plain Sub signal?

Yes I believe it will modify Bass, but just according to room correction and nothing else. When it said for multichannel “without surround sound processing” I think it means that it is not doing any extra processing to determine virtual surround channels or up mixing speakers channels, I.e. playing a 5.1 source on 7.1 speaker system will stay just 5.1. Those are called DTS Neural X, Dolby Surround, Surround Virtual listening modes.

Thank you. I got a pretty well working Multichannel setup now. Seems to be the best solution in my case. Even if „direct“ seems to be instinctively the „right“ solution. But after screwing a bit, Multichannel sounds good now. And I don’t need to worry about losing Bass anymore.

??

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.