What Sound goes to how many, which Channels, when, & do any processors let you change that config? Wait, What? (1 Viewer)

[Josh Dial]

But, if I’m wrong, PLEASE TELL ME because I’d LOVE TO KNOW… I haven’t found another solution (other than the Monolith HTP-1).

You are sort of wrong (and certainly wrong to say even if your AVR has wide capabilty it will not engage them).

There are a lot of factors here.

Atmos and DTS:X both take an existing "bed" layer and add either additional audio channels or discrete objects and play those additional channels or objects through height speakers.

The additional audio can be channels or tracks. Let's assume you are watching a movie. The film's creatives may have decided to use the height channels to play ambient music to reinforce the aesthetic of the scene. Maybe the scene takes place in a loud dance club so pushing the music through the heights make it sound all around you. In that example the heights are used for channels.

The additional audio can also be for objects. Maybe later in the same movie example the action moves from inside the dance club to outside and there is a helicopter flying around. The creatives can stop pushing the music through your heights as channels (maybe the music is gone or only plays in your surrounds) and instead push object-based audio information through your heights. The helicopter will move from height speaker to height speaker or even around all your speakers. In any event, the height speakers are being used to place an object.

It's a tad more complicated than that but it should suffice for our purposes.

The bed layer contains up to 7 channels plus the LFE (again, this is for home releases only, not theatres). In other words, Atmos and DTS:X are built upon a 7.1 bed layer.

Front wide speakers can be added to a 7.1 system to make a 9.1 system. However--and this is important--the extra 2 channels may not be discrete channels. In 5.1 and 7.1 each channel contains discrete audio (or, at least, it can). In 9.1 what goes to those extra 2 channels depends on your processor. If your processor can do Atmos or DTS:X then those 2 front wide speakers are fed either 2 front wide channels or objects. They are discrete. If your processor cannot do Atmos or DTS:X but otherwise supports front wide speakers, then those 2 speakers will be fed matrixed information from your front and centre channels with a bit of reverb added in.

Ultimately it's probably more useful to think of front wide channels as being extra speakers like your height speakers in which the creatives can place channels and objects.

But it's up to the source media to use the additional channels.

In the end, what you can play depends on a number of factors:

1. The audio track. If the source isn't using speakers well or at all then there's nothing you can do (except maybe use upsampling like Dolby Surround or DTS: Neural X to force audio into all your speakers).
2. Your processor. If you can process 15 discrete channels, then you will absolutely be able to play 9.x.6 tracks, subject to your ability to amplify those channels.
3. Your amplification. You obviously need to be able to amplify your channels. If you can decode 15 channels but only amplify 11, you are stuck with 7.x.4 or 9.x.2.

If your setup can process and amplify 15 channels and you are playing an Atmos or DTS:X track then you will 100% get sound through every speaker. Whether that sound is meaningful or not will be up to the creatives. Having front wides and 6 height speakers won't impress you much if the creatives are merely pumping some background music through them all.

 

[SFS]

You are sort of wrong (and certainly wrong to say even if your AVR has wide capabilty it will not engage them).

There are a lot of factors here.

Atmos and DTS:X both take an existing "bed" layer and add either additional audio channels or discrete objects and play those additional channels or objects through height speakers.

The additional audio can be channels or tracks. Let's assume you are watching a movie. The film's creatives may have decided to use the height channels to play ambient music to reinforce the aesthetic of the scene. Maybe the scene takes place in a loud dance club so pushing the music through the heights make it sound all around you. In that example the heights are used for channels.

The additional audio can also be for objects. Maybe later in the same movie example the action moves from inside the dance club to outside and there is a helicopter flying around. The creatives can stop pushing the music through your heights as channels (maybe the music is gone or only plays in your surrounds) and instead push object-based audio information through your heights. The helicopter will move from height speaker to height speaker or even around all your speakers. In any event, the height speakers are being used to place an object.

It's a tad more complicated than that but it should suffice for our purposes.

The bed layer contains up to 7 channels plus the LFE (again, this is for home releases only, not theatres). In other words, Atmos and DTS:X are built upon a 7.1 bed layer.

Front wide speakers can be added to a 7.1 system to make a 9.1 system. However--and this is important--the extra 2 channels may not be discrete channels. In 5.1 and 7.1 each channel contains discrete audio (or, at least, it can). In 9.1 what goes to those extra 2 channels depends on your processor. If your processor can do Atmos or DTS:X then those 2 front wide speakers are fed either 2 front wide channels or objects. They are discrete. If your processor cannot do Atmos or DTS:X but otherwise supports front wide speakers, then those 2 speakers will be fed matrixed information from your front and centre channels with a bit of reverb added in.

Ultimately it's probably more useful to think of front wide channels as being extra speakers like your height speakers in which the creatives can place channels and objects.

But it's up to the source media to use the additional channels.

In the end, what you can play depends on a number of factors:

1. The audio track. If the source isn't using speakers well or at all then there's nothing you can do (except maybe use upsampling like Dolby Surround or DTS: Neural X to force audio into all your speakers).
2. Your processor. If you can process 15 discrete channels, then you will absolutely be able to play 9.x.6 tracks, subject to your ability to amplify those channels.
3. Your amplification. You obviously need to be able to amplify your channels. If you can decode 15 channels but only amplify 11, you are stuck with 7.x.4 or 9.x.2.

If your setup can process and amplify 15 channels and you are playing an Atmos or DTS:X track then you will 100% get sound through every speaker. Whether that sound is meaningful or not will be up to the creatives. Having front wides and 6 height speakers won't impress you much if the creatives are merely pumping some background music through them all.

Thanks for your reply. James Larson of Audioholics disagrees with your assessment of how wides are engaged. I’m not saying you’re wrong, maybe he is.

As noted in his Audioholic’s review of the Monolith HTP-1 processor, most Atmos tracks are LOCKED at 7.x.4 and therefore most AVRs/processors CANNOT add wides EVEN IF THEY CAN PROCESS 15ch. Nor can they add center top channels if you’re set up for x.x.6. And to be clear: they cannot add discreet NOR matrixed/upmixed wide channels.

The Monolith HTP-1 is the only “reasonably priced” processor that can add channels to a locked atmos bed track. Perhaps Trinnov can, but their processors are crazy expensive. Please let me know if there are any AVRs that can do it! My Marantz AVR cannot even though it does have wide channel processing. Remember, just because an AVR can process 15ch, doesn’t mean they can unlocked a restricted Atmos track.

Please check out the Audioholics article (scroll down to the section on “Front Wides”)… let me know if Audioholics is wrong!

DTS seems to have a bit more functionality, and does use wides to a VERY limited extent in some cases.

Again thanks for your input. It helps flesh out what is really going on. Someone is wrong or not getting the full story. Perhaps Audioholics is just pumping the Monolith (?). Please let me know your thoughts on the Audioholics article.

 

[Josh Dial]

Thanks for your reply. James Larson of Audioholics disagrees with your assessment of how wides are engaged. I’m not saying you’re wrong, maybe he is.

I think he is partly wrong. We're also partly saying the same thing. I also don't agree with one of his claims.

As I noted above, a key piece of the puzzle is the source media (this is literally #1 in my 3 points). If your media only has 8 channels (i.e. 7.1), then the only way to engage front wides will be through matrixing. If you play a 7.1 track and turn on matrixing, your system will absolutely play through your front wides. There is no "locked" (also called "pinned down") setting that can prevent your device from matrixing. He's wrong there (though maybe he's just saying what I say in my next paragraph).

That said, there are many "locked" Atmos tracks that limit your playback to the reported channels. You'll often see this on the back of a UHD/blu-ray disc as "7.1.4 Atmos" or similar. In those cases, your front wides will not be engaged, even if your processor can process them EXCEPT through matrixing which will, in turn, negatively affect the experience because it will disable Atmos, pair down to the 7.1 base layer, and then upscale to 9.1.4. In other words, if a track is locked you will only be able to play it that format (Atmos or DTS:X) with the reported number of channels.

If your media reports simply "Atmos" or "DTS:X" without noting the number of channels, then it's likely it is unlocked, in which case you'll be able to play as many channels as your system supports, up to the limit of home media (which is typically 32). However, even some unlocked tracks have "hidden" limits. It's all very wild west.

The opinion I disagree with is his claim that 9.x.2 is better than 7.x.4, or, put another way, that adding front wides is more impactful than having front and back height channels. I think the opposite is true. All adding front wide speakers typically does is make your room sound larger and the front soundstage more expansive. Creatives almost never use front wides in any meaningful way. Even worse, matrixed sound to front wides (including through Monoprice's tech) barely does anything to positively affect the movie watching experience. Using front and back height speakers, however, does improve the experience. Creatives are increasingly using height speakers for objects and not merely for music or "boring" audio channels. It's far more noticeable, impactful, and just plain fun to hear an object pan around four overhead speakers. You can absolutely notice objects moving across four speakers. You can barely notice front wides.

 

[JohnRice]

“Wide” speakers aren’t an official part of any surround format. I think a lot of people don’t know that. Terms get tossed around with no understanding of how they’re being used. It creates a lot of confusion.

 

[JohnRice]

That said, there are many "locked" Atmos tracks that limit your playback to the reported channels. You'll often see this on the back of a UHD/blu-ray disc as "7.1.4 Atmos" or similar. In those cases, your front wides will not be engaged

I've never noticed that. Would you provide some examples? Maybe I have one of them.

 

[SFS]

I think he is partly wrong. We're also partly saying the same thing. I also don't agree with one of his claims.

As I noted above, a key piece of the puzzle is the source media (this is literally #1 in my 3 points). If your media only has 8 channels (i.e. 7.1), then the only way to engage front wides will be through matrixing. If you play a 7.1 track and turn on matrixing, your system will absolutely play through your front wides. There is no "locked" (also called "pinned down") setting that can prevent your device from matrixing. He's wrong there (though maybe he's just saying what I say in my next paragraph).

That said, there are many "locked" Atmos tracks that limit your playback to the reported channels. You'll often see this on the back of a UHD/blu-ray disc as "7.1.4 Atmos" or similar. In those cases, your front wides will not be engaged, even if your processor can process them EXCEPT through matrixing which will, in turn, negatively affect the experience because it will disable Atmos, pair down to the 7.1 base layer, and then upscale to 9.1.4. In other words, if a track is locked you will only be able to play it that format (Atmos or DTS:X) with the reported number of channels.

If your media reports simply "Atmos" or "DTS:X" without noting the number of channels, then it's likely it is unlocked, in which case you'll be able to play as many channels as your system supports, up to the limit of home media (which is typically 32). However, even some unlocked tracks have "hidden" limits. It's all very wild west.

The opinion I disagree with is his claim that 9.x.2 is better than 7.x.4, or, put another way, that adding front wides is more impactful than having front and back height channels. I think the opposite is true. All adding front wide speakers typically does is make your room sound larger and the front soundstage more expansive. Creatives almost never use front wides in any meaningful way. Even worse, matrixed sound to front wides (including through Monoprice's tech) barely does anything to positively affect the movie watching experience. Using front and back height speakers, however, does improve the experience. Creatives are increasingly using height speakers for objects and not merely for music or "boring" audio channels. It's far more noticeable, impactful, and just plain fun to hear an object pan around four overhead speakers. You can absolutely notice objects moving across four speakers. You can barely notice front wides.

Thanks for your reply.

So to be clear:

1) you cannot add wides to a locked atmos track unless you turn off Atmos, and instead matrix the channels, which basically defeats the purpose of Atmos.

2) it’s not always clear if an atmos track is locked, but most atmos tracks are locked.

That’s basically the point I’m trying to make. People should know that even if you have a 15ch AVR or processor, you’ll usually only get 7.1.4 atmos anyway.

You’ll need to turn off Atmos to use all 15 channels. That’s not a trivial limitation and might make people think twice before spending $4000 to basically get nothing more than they already get with a 11ch AVR. That’s why I didn’t bother upgrading to 15ch, even though I’m set up for it (I’m actually set up for 17ch). I decided to spend the money on a 83” OLED instead.

As for 7.1.4 vs 9.1.2, I have to say I agree with both James Larson and Anthony Grimani. I’ve tested different set ups extensively. 9.1.2 is by far the best format, at least in my room. Personally I miss Audessey’s DSX’s wide mode, and I find it far more immersive than Atmos. But given that wides are rarely used these days in bed tracks, the debate between 7.x.x vs 9.x.x is kinda moot.

As for 2 vs 4 atmos speakers, in my experience, it’s no contest. 2 in the middle is much better, at least in my room. When I engaged my 4 atmos speakers (2 top front + 2 top back) there is a massive hole above me and I never get the over head effect. The atmos channels are vague and far way. To say “underwhelming” is an understatement. But when I use 2 middle atmos speakers, the difference is MASSIVE. The sound is literally above me and I am totally immersed. I suggest you read up on Grimani’s work on the subject. Dolby’s suggested speaker placement is not ideal (and never was even pre-atmos). IMHO Atmos speakers should be placed much closer together and closer to the viewer than Dolby recommends. Dolby recommends 70-120 degree separation. IMHO the target should be 60 degrees. I cannot tell you how angry I was to learn this AFTER I finished my home theatre. Not that easy to move ceiling speaker. Lol.

 

[SFS]

I

(Sorry, posted same thing twice)

 

[Josh Dial]

With the greatest respect to Anthony Grimani, he vastly overstates the importance of front wides, which, as John correctly noted above, are not really part of any home format at all (this reality is what partly drives the fact that many Atmos/DTS:X tracks use a 7.1 base layer).

Grimani bases his conclusion off of acoustics and acoustics only. He says that to have a more "immersive" audio experience front wides are needed (to be clear, in this video he says they are "equally important" to height speakers, not more"). That focuses on how audio leaves the speakers and bounces off surfaces (or go right to your ears) creating a large field of sound. Undoubtedly front wides serve to create a larger field.

However, what Grimani ignores--and what I think you are ignoring, Bob--is that the channels only deliver what the creatives choose to send. Front wide channels simply just aren't used to (90% of the time) deliver anything other than the same information already being sent to your LCR channels. In almost all cases, front wides are duplicative and only serve to widen the field of sound. I highly doubt this will ever change.

Height channels are used by creatives to place objects. This is happening more and more. In my view this use will continue to increase.

Frankly, based on your description of how you used the Audyssey DSX wide mode, I think you are placing greater weight on your speakers being "filled" with sound, rather than being filled with meaningful sound, which is what I prefer. DSX takes 5.1 and 7.1 and upmixes. It's very good, but the results aren't driven at all by creatives. When DSX mode is on, the audio you hear in your front wides or two height speakers weren't placed there by a human: they were placed there by math.

So, in my opinion, a listener is better served by four height channels than two height channels and two front wides. The former will present you with more detailed sound. The latter will just have more sound.

 

[JohnRice]

As for 2 vs 4 atmos speakers, in my experience, it’s no contest. 2 in the middle is much better, at least in my room. When I engaged my 4 atmos speakers (2 top front + 2 top back) there is a massive hole above me and I never get the over head effect.

It sounds to me as if the layout of your overhead speakers is incorrect. Maybe I'm reading in too much into it, but they aren't "front" and "back." They are toward the front and rear, but ideally only about 30 degrees. It will also depend on the dispersion of the speakers and if they aim straight down or are angled.

 

[JohnRice]

Dolby recommends 70-120 degree separation. IMHO the target should be 60 degrees. I cannot tell you how angry I was to learn this AFTER I finished my home theatre. Not that easy to move ceiling speaker. Lol.

I have never seen anything from Dolby that even comes close to suggesting 120 degree separation. The official Dolby pages I've looked at gave a maximum of 80 degrees total (+/-40 degree) with the target area being +/- 30-35 degrees.

 

[JohnRice]

Front wide channels simply just aren't used to (90% of the time) deliver anything other than the same information already being sent to your LCR channels. In almost all cases, front wides are duplicative and only serve to widen the field of sound. I highly doubt this will ever change.

My impression, because I've never used front wides, is that they just matrixed the front L&R. IOW, created a differential channel similar to the surrounds in original Dolby Surround. I don't know what else they could actually do. They can't create something out of nothing.

From something you said, it's unclear that if a room is equipped with three pairs of overhead speakers or two pairs of side surrounds with a suitably equipped Atmos processor, would the "extra" pair of speakers beyond 7.x.4 not be actually be used in many cases? I had never heard of that before.

 

[SFS]

It sounds to me as if the layout of your overhead speakers is incorrect. Maybe I'm reading in too much into it, but they aren't "front" and "back." They are toward the front and rear, but ideally only about 30 degrees. It will also depend on the dispersion of the speakers and if they aim straight down or are angled.

Sorry, Dolby calls them top front and top rear (not top back). My placement is exactly as per Dolby’s recommendations: 45 degree in front of the main position, 135 degrees behind. The angle in between the speakers is therefore 90 degrees, which results in a giant gap above my head and too wide for any imaging (assuming the creatives intend to image anything above you, perhaps not). They are pointed straight down, and perhaps don’t have wide enough dispersion, that’s why I don’t like it in my set up, and much prefer using only my top middle speakers instead.

 

[SFS]

I have never seen anything from Dolby that even comes close to suggesting 120 degree separation. The official Dolby pages I've looked at gave a maximum of 80 degrees total (+/-40 degree) with the target area being +/- 30-35 degrees.

Dolby recommends up to 30 degree in front of the main spot and up to 150 behind. Therefore up to 120 degrees between the front row and rear row. The min they recommend is 70 apart, which is still too far apart… 70 should be the max, not min. I set my 90 degrees apart as per the recommendation (45 in front, 135 behind, just like the diagram below).

And the other problem is Dolby’s recommended angle between ceiling speakers in the same row is also way too wide. They don’t specify the angle in the diagrams but they appear 90 degrees apart.

 

[SFS]

My impression, because I've never used front wides, is that they just matrixed the front L&R. IOW, created a differential channel similar to the surrounds in original Dolby Surround. I don't know what else they could actually do. They can't create something out of nothing.

From something you said, it's unclear that if a room is equipped with three pairs of overhead speakers or two pairs of side surrounds with a suitably equipped Atmos processor, would the "extra" pair of speakers beyond 7.x.4 not be actually be used in many cases? I had never heard of that before.

I have 3 pairs of ceiling speakers. I’m not sure what you are asking.

My understanding from Audioholics is that if the atmos mix is locked to 7.1.4, which most are, the top middle are never used.

 

[SFS]

With the greatest respect to Anthony Grimani, he vastly overstates the importance of front wides, which, as John correctly noted above, are not really part of any home format at all (this reality is what partly drives the fact that many Atmos/DTS:X tracks use a 7.1 base layer).

Grimani bases his conclusion off of acoustics and acoustics only. He says that to have a more "immersive" audio experience front wides are needed (to be clear, in this video he says they are "equally important" to height speakers, not more"). That focuses on how audio leaves the speakers and bounces off surfaces (or go right to your ears) creating a large field of sound. Undoubtedly front wides serve to create a larger field.

However, what Grimani ignores--and what I think you are ignoring, Bob--is that the channels only deliver what the creatives choose to send. Front wide channels simply just aren't used to (90% of the time) deliver anything other than the same information already being sent to your LCR channels. In almost all cases, front wides are duplicative and only serve to widen the field of sound. I highly doubt this will ever change.

Height channels are used by creatives to place objects. This is happening more and more. In my view this use will continue to increase.

Frankly, based on your description of how you used the Audyssey DSX wide mode, I think you are placing greater weight on your speakers being "filled" with sound, rather than being filled with meaningful sound, which is what I prefer. DSX takes 5.1 and 7.1 and upmixes. It's very good, but the results aren't driven at all by creatives. When DSX mode is on, the audio you hear in your front wides or two height speakers weren't placed there by a human: they were placed there by math.

So, in my opinion, a listener is better served by four height channels than two height channels and two front wides. The former will present you with more detailed sound. The latter will just have more sound.

Fair enough. I like wides even if they are essentially fake channels. And like I said, it’s basically a moot point now anyway… no one uses them much, and matrixing requires giving up true atmos, so it’s a lost battle, I get it.

And like I said, in my set up, the 4 ceiling speakers are unconvincing, perhaps due to the speakers being set way too far apart and away from the listener. I much prefer the object being placed ABOVE me, not several feet away from me… personal preference perhaps. Bottom line, I just can’t tell that where the sound is coming from (I just hear a vague smear far around me) and I can’t even tell if it’s above me at all, and that kinda defeats the purpose of object based audio. Maybe my ceilings are too low?

 

[JohnRice]

Sorry, Dolby calls them top front and top rear (not top back). My placement is exactly as per Dolby’s recommendations: 45 degree in front of the main position, 135 degrees behind. The angle in between the speakers is therefore 90 degrees, which results in a giant gap above my head and too wide for any imaging (assuming the creatives intend to image anything above you, perhaps not). They are pointed straight down, and perhaps don’t have wide enough dispersion, that’s why I don’t like it in my set up, and much prefer using only my top middle speakers instead.

If I was in your situation, I’d at least try using the middle overhead with just the front or rear to see which one I liked best. So, front and middle, then middle and rear. Can’t hurt to try.

 

[SFS]

If I was in your situation, I’d at least try using the middle overhead with just the front or rear to see which one I liked best. So, front and middle, then middle and rear. Can’t hurt to try.

Oh I’ve tried Over and over and over again. Once you use middle + front, or middle + rear, the middle gets virtually nothing. There is a clear bias towards sending the atmos signal to the front row and rear row. Hence I use only the top middle row to basically disable that bias.

 

[JohnRice]

You’re not understanding my suggestion. To be honest, this is wearing me out. I’m going to bail out on the whole issue.

 

[SFS]

You’re not understanding my suggestion. To be honest, this is wearing me out. I’m going to bail out on the whole issue.

Sorry, I literally said exactly what you said.

 

[SFS]

Guys, I really appreciate all your comments. I don’t mean to wear anyone out.

Just to recap, my original point was just to warn people that it is misleading to say you can run 15ch if your AVR can process them (and you can power them of course) without also warning them that if they intend to use pure Atmos, which you all obviously prefer over matrixing, that there is no need for more than 11ch (7.1.4) on most atmos content. I asked if I was wrong, some of you guys kinda said I was wrong, but then basically repeated what I said anyway: you can’t use wides (nor would you want to) if the atmos track is locked to 7.1.4 (which most are, according to Audioholics anyway)

As far as 9.x.2 vs 7.x.4, I was just giving my preference, as you did giving yours. Then somehow it turned into a misunderstanding about Dolby’s angles. Unless Dolby has some other guide, the angles are pretty clear - they are very widely spaced… too much for my room. I’ve never seen anywhere where Dolby recommends 80 degree separation as a max… they recommend 90 as the ideal. But I suspect you misunderstood how I was measuring the angles, but that’s cool. No worries. I’m here to learn.

And to be clear I have tested:
1) front and middle: result: middle gets virtually nothing.
2) middle and rear: result: middle gets virtually nothing.

I do appreciate the rebuttals to Grimani and Audioholics. G’nite guys.