Atmos vs 5.1

QuadraphonicQuad

Help Support QuadraphonicQuad:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Just so you know I failed typing in high school. Kept hitting the wrong keys because I had my eye on the beautiful girl who sit beside me while I was typing. Some things never change.
s no big deal. i tooks the evelyn wood head sped redding course, and now i ma master at comprehesion n tiping.
 
As far as I have been able to read and understand on this topic, at least for TrueHD 7.1 (I don't know the details for EAC3-JOC), the Dolby Atmos encoding from the ADM master file generates up to the 4 called “Substreams” in the TrueHD 7.1 file. This to achieve backwards compatibility and playability on older systems.

Each of the “Substreams” can be recognized (or not) and decoded by each particular AVR/Processor.
I personally visualize each TrueHD Atmos mix as having 4 packages, each package fits inside the previous one, the first and primary package/substream is the stereo one, ...the more expansive your system is, the more packages your AVR/media player can see, use and then unpack/unfold:

#1. The stereo package: the whole mix summed to just LEFT + RIGHT.

#2. The 5.1 package: the LFE & Center are unpacked, ...whatever is "in the back" of the overall mix is sent to the side-surrounds. All of that unpacked/unfolded audio is then 'subtracted' from the front pair.

#3. The 7.1 package: simply unfolds two channels from the side-surrounds and then gets 'subtracted' from the sides.

#4. The Atmos package.

I'm not sure how accurate this breakdown is, but for me, it is an easier concept to grasp. This way of looking at it also doesn't use the concepts of down-mixing or a "fold-down" in the traditional sense.
 
Last edited:
I rip everything i buy. For stereo I'm trying to decide if I've ever had to resort to ripping the True HD stream. There always seems to be an LPCM option on the disc. Either 24/48 or 24/96.
 
I personally visualize each TrueHD Atmos mix as having 4 packages, each package fits inside the previous one, the first and primary package/substream is the stereo one, ...the more expansive your system is, the more packages your AVR/media player can see, use and then unpack/unfold:

#1. The stereo package: the whole mix summed to just LEFT + RIGHT.

#2. The 5.1 package: the LFE & Center are unpacked, ...whatever is "in the back" of the overall mix is sent to the side-surrounds. All of that unpacked/unfolded audio is then 'subtracted' from the front pair.

#3. The 7.1 package: simply unfolds two channels from the side-surrounds and then gets 'subtracted' from the sides.

#4. The Atmos package.

I'm not sure how accurate this breakdown is, but for me, it is an easier concept to grasp. This way of looking at it also doesn't use the concepts of down-mixing or a "fold-down" in the traditional sense.
You know none of this is done on the fly right? They are all complete mixes.

I've often wondered how one can select, say the 5.1 mix. It's not on any of the menus unless it's a stand alone dedecated mix. I also wonder if you select stereo playback if it plays the substream or the LPCM layer.
 
You know none of this is done on the fly right? They are all complete mixes.

I've often wondered how one can select, say the 5.1 mix. It's not on any of the menus unless it's a stand alone dedecated mix. I also wonder if you select stereo playback if it plays the substream or the LPCM layer.
You cannot select any of the substreams on a TrueHD Atmos via the Blu-ray menu. It is just a "single" track.

The AVR itself can "select" to decode different substreams in that track, depending on its decoding functionality capabilities or on the Audio Options you may set manually.

If you can select the 5.1 or the stereo mix from the Blu-ray menu, then the specific different track apart from the TrueHD Atmos is played.
 
Atmos v 5.1? I'm non-binary when it comes to MCH music. Quad, 5.1, Atmos -- I just love it all. I guess I'm what you'd call 'amultichannel'. There must be others out there like me.

Sure! I love a good stereo mix, too. As I often say, I always listen to all the mixes included in a given release. I think it's just great to have the opportunity to listen to the same album in different presentations.
 
Atmos v 5.1? I'm non-binary when it comes to MCH music. Quad, 5.1, Atmos -- I just love it all. I guess I'm what you'd call 'amultichannel'. There must be others out there like me.
I have a large number of monophonic recordings that I still enjoy. On Monday, when the Marantz 7706 goes on sale, I’ll be one step closer to 5.1.4.

And everything in between.
 
Looks like a nice unit. Even has analog mch input! HDMI 2.1, etc etc.
I'm stoked for you!
I’ve had a 7701 for about ten years, so this looks like it’s going to be a fairly easy upgrade. I still need a six=channel amp to replace the stereo one that’s running my rears. The speakers have been in place since I built the room.
 
I guess that's the part I'm not clear on. So there is a 2 way communication between the AVR and the disc player?
Disc player delivers encoded signal.
AVR decodes full 7.1.4 or 9.1.6 mix.
Speaker management settings are applied and downmixing happens if set to do so.

Any nuts and bolts internal to the decoding process and backwards compatibility are academic.
 
Disc player delivers encoded signal.
AVR decodes full 7.1.4 or 9.1.6 mix.
Speaker management settings are applied and downmixing happens if set to do so.

Any nuts and bolts internal to the decoding process and backwards compatibility are academic.
Huh??? Is that supposed to be a response to my question?
 
You know none of this is done on the fly right? They are all complete mixes.

I've often wondered how one can select, say the 5.1 mix. It's not on any of the menus unless it's a stand alone dedecated mix. I also wonder if you select stereo playback if it plays the substream or the LPCM layer.
Why would you want to select the 5.1 mix? It's in lossy Dolby Digital AC3 and while it can be at 640kbps (the max for AC3) it is far more likely to be at a lower bit rate and sound poor as a result. Much better in my view to play the 7.1 MLP and have your AVR fold the two sets of rears together to get 5.1 (or 5.0 in my case), it's a trivial thing for your AVR to do and likely an identical mix to the AC3 5.1. I suspect the AC3 is always generated automatically from the 7.1 MLP in the Atmos workflow, even if there is a separate DTS HD MA 5.1 mix on the disc it seems unlikely to me that will be put into the Atmos workflow just for the AC3 5.1.
 
Back
Top