Has Dolby Home Atmos Been a Step Forward for Home Audio?

Do you think Dolby's Home Atmos hasbeen a positive move on the whole for home audio?

  • Yes, Home Atmos has been a move in the right direction.

    Votes: 27 50.9%
  • Dolby's Home Atmos has overall been good for home audio but has some flaws.

    Votes: 19 35.8%
  • Home Atmos has become a misbegotten mess for home audio.

    Votes: 6 11.3%
  • I don't know what a Dolby Home Atmos is. Help, I am lost and scared!

    Votes: 1 1.9%

  • Total voters
    53
R

RXP

Audioholic Intern
Object based sound is good in principle. The demo clips we've all heard are proof of that. The ones where Dolby goes from 5.1 to full Atmos shows the power clearly.

However, in real world content it's simply not a big step up compared to simple upmixing. Movies are too loud, there's too much going on the screen, in the audio everywhere for you to even notice the location of sounds. Therefore, upmixing suffices and accuracy isn't an issue. The bubble is what we're enjoying and it doesn't need to be discrete.

An example of where a film really did use Atmos well was Roma. Good article on it here: Roma’: Alfonso Cuarón Proved Dolby Atmos Is the Perfect Tool for Intimate Films, Not Blockbusters. It was a quiet film and the sound really put you into it.
 
Philnick

Philnick

Enthusiast
TLS guy: Look in a mirror. You'll see fleshy ear trumpets (called "pinnae") surrounding your ears, which focus your ears' sensitivity forwards. (Holding up sunglasses was not their original design intent.) The engineers who create surround mixes have pinnae too. They sit facing forwards while creating the surround mix, as do we while listening to it.

It's only the penny-pinching decision by AVR manufacturers to include with their products microphones that aren't oriented the same way as our ears that leads automatic room correction systems to distort the mix created by the sound engineers by reducing the volume of the rear and overhead speakers because the AVR hears those speakers sounding louder than we or the engineers do.

In a theater with a dome screen that wraps over and around all three hundred and sixty degrees behind us (like a planetarium), and a tilt and swivel chair to be able to follow the action in any direction - and action that really does move all around us - omnidirectional mikes might make sense. I don't have a theater, or films, like that. Do you?

I'm not about to cut off my pinnae just to make my hearing match what budget microphones lead Audessy and YPAO to do automatically. I suspect that there are evolutionary advantages to the pinnae's effect on our hearing - and I do sometimes wear sunglasses. Far better to make a minor tweak to the result of the auto-room correction routine.
 
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R

RXP

Audioholic Intern
Interesting opinion! Are there any directional mics we can use to set levels accurately? I myself have a sound professionals binural mic that I could monitor in REW.
 
Philnick

Philnick

Enthusiast
Any cardioid microphone aimed at the screen would give the right orientation, but it would also have to have the same gain and frequency response as the stock mike or it would lead the AVR to add coloration to the sound.

If you use an external program for just setting levels after using the stock mike to run the normal routine, that might not be a problem. Does your binaural mike focus on sound from the front? I don't recall whether the pictures of binaural "head" mikes I saw long ago had pinnae. UPDATE: Just did a search for "binaural microphone picture"- they all have ears! However, some of them are pretty pricey. Traveling the test tone around the room and level-matching the channels by ear while facing forward may not be as precise, but it's free.

PS The term cardioid means "heart-like." Visualize a Valentine heart spun in three dimensions around a vertical line bisecting the heart, with the head of the mike in the dimple facing down. Elongate the pattern and you have the basic idea of what the pickup pattern looks like.
 
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R

RXP

Audioholic Intern
The binural mics I have are actually for your own ears to make recordings with. I use mine to simulate my real loud speaker system over headphones using a tool called impulicfer. They are like in ear headphones.

I'll do some experiments tomorrow with summing the two mics to mono and trying to get an SPL readout on REW. I'll play the white noise to the centre channel and set levels to all channels based on the binural SPL.

Edit: these are the mics I have, except mine are the XLR version.
 
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TLS Guy

TLS Guy

Audioholic Slumlord
TLS guy: Look in a mirror. You'll see fleshy ear trumpets (called "pinnae") surrounding your ears, which focus your ears' sensitivity forwards. (Holding up sunglasses was not their original design intent.) The engineers who create surround mixes have pinnae too. They sit facing forwards while creating the surround mix, as do we while listening to it.

It's only the penny-pinching decision by AVR manufacturers to include with their products microphones that aren't oriented the same way as our ears that leads automatic room correction systems to distort the mix created by the sound engineers by reducing the volume of the rear and overhead speakers because the AVR hears those speakers sounding louder than we or the engineers do.

In a theater with a dome screen that wraps over and around all three hundred and sixty degrees behind us (like a planetarium), and a tilt and swivel chair to be able to follow the action in any direction - and action that really does move all around us - omnidirectional mikes might make sense. I don't have a theater, or films, like that. Do you?

I'm not about to cut off my pinnae just to make my hearing match what budget microphones lead Audessy and YPAO to do automatically. I suspect that there are evolutionary advantages to the pinnae's effect on our hearing - and I do sometimes wear sunglasses. Far better to make a minor tweak to the result of the auto-room correction routine.
That post is totally illogical and makes zero sense.

I have my pinnae in the concert hall and my AV room. So in the concert hall my ears will favor the forward sound. So then in the reproduced sound you want the same balance of forward, side, rear and ceiling sound. Then it will sound realistic, which it does. If you go turning up the rear, side speakers and Heaven knows what else, you HAVE destroyed and violated the natural balance.

Wherever you are, you are focused on the forward sound. In the concert Hall, opera house you are never actually aware of the reverberant field expect as a delayed after echo in a reverberant space.

So that is the way it should sound in an AV room. In multi channel disc of antiphonal music where there are instrumentalist or singers in the rear then that is the way it is clearly reproduced as the composer intended. In my room the balance is correct on that program. i have to say Audyssey sets these levels correctly and the same as my calculations.

Lastly an omni directional microphone is the correct instrument for setting these levels and NOT a cardoid directional one.
 
T

Trebdp83

Audioholic Chief
Oh, this is good stuff. Don’t stop. I just need to plug the Denon back into the outlet. Where the hell is that last pan of Jiffy Pop?!!!
 
TLS Guy

TLS Guy

Audioholic Slumlord
Still slow site response, but I have to respond (having Auro-3D with 11.1.6)

I've played with numerous configurations with or without "top middle" (acting like a dual VOG "middle" in some respects) and also shrinking the room down to effectively half size (moving rear height to "top middle" instead with only side surrounds). Let's call that "small room" with Auro-3D and Atmos and X.

Small room with heights.... Works fine. FULL overhead sound on ceiling. Think of it this way. It will pan between the front/rear heights at whatever height level they're at. If that height level is essentially on the ceiling (even if at 30/150 angles), it still PANS in a straight line across that height "plane" (an inch or two from the ceiling). There is effectively NO DIFFERENCE from "tops" speakers in this size room except that the sounds start next to the screen instead of 1/4 the way out into the room.

Longer room with heights. Once you get past a 120 degree angle (perhaps slightly less or more depending on how tall you are and other factors), the "directly overhead" (90 degree elevation straght up) starts to come apart like you're sitting in a gazebo blocking sound above you. This is what people who think "heights suck" are probably experiencing. Their rooms are too large for height speakers without option #3. the same thing would eventually happen with tops speakers also if you lengthen the room even further (say a 40 foot long room). It's just the angle between the two sets of speakers relative to your ears that limits the phantom imaging directly overhead.

OPTION: Add "Top Middle" speakers. This bridges the distance in either case. It's MORE effective, IMO with heights than tops in most home rooms simply because they need them more. Note that if you mount tops at 45 degrees relative to ONE row of seats, it will always pan fine overhead because the distance apart between the two is small enough to work fine. But you can't cover 4 rows of seats with two sets of ceiling speakers 45 degrees apart. It just won't work. Thus, it's the same problem as the room gets larger. This is why cinema Atmos has many many overhead speakers and why home Atmos has up to TEN speakers overhead (that's enough to cover like 6-12 rows depending on the spacing. You can go further by adding matrixed pairs (20 sets of overheads). That could get you up to 24 rows I think or 10 rows of really comfy recliners).

In any case, heights + top middle (or VOG) = direct overhead sounds work fine. For longer rooms, you will want surround and rear heights (copied) for Auro-3D to give full coverage (same for rear bed surrounds if you don't have a 13.1 Auro capable system). I use my surround heights PLUS the rear heights by extracting the surround heights as a "middle" point (like top middle) instead and that stretches it across the entire room (24 ceiling). Copying the rear height to surround height also works fine for all three rows (sounds pretty good, IMO).

Auro-3D movies handled like THAT are great sounding. Atmos is only slightly better in my room with 11.1.6 (Auro uses 9.1.6 here). With 13.1 Auro, it would sound as good or better than Atmos 7.1.6 up to 9.1.6 as it pretty much covers the same range (plus the options of center height and VOG to "lock" the sound into place for off-axis rows (something Atmos CANNOT do!)

Auro-3D music doesn't use direct overhead much (most music albums don't employ the VOG channel) and even with an extracted top middle, little goes up there. They're just not mixed (or recorded in the case of dual-quad miked recordings) that way. I mean how many instruments are on the ceiling in a concert hall?

Even some true Auro-3D movie mixes (like Death Machine) have a more "wall of sound" type mix (thunder was directly overhead in that movie, most most other scenes were wall to wall sound instead). Other movies like Flatliners sound JUST LIKE the Atmos version with voices wandering all over the ceiling in pretty much the exact same places!

The other thing I would address is Atmos not being good for music with ceiling speakers. I think this is because some home Atmos systems have "too much separation" between bed and overhead speakers. You get the same kind of gap mid-wall as you get with heights directly overhead if there's too much distance to the ceiling (e.g. a 10 foot ceiling might have issues with ear level speakers at 3.5 feet or something; I can't be sure of the exact numbers needed since I haven't heard them in person, but at some distance it will do that. You'll have ear level and overhead and little in-between. With heights and ear level, you typically have a nice smooth transition between the layers to the point where you can't tell where one ends and the other begins assuming the speakers match well. But then you might have the direct overhead issue without top middle added so....

The bottom line is that "perfect" Atmos needs more than 11-speakers in a larger room. For small rooms, 11 is probably enough for a nice ear to ceiling bubble, but then in that sized room heights and tops will both work. As the room gets larger, you have to pick between priority with that many speakers (strong overhead or smooth transition with full ceiling coverage). Add more speakers and you don't have to compromise.

The full ceiling is another matter. If you go with tops in a 24' long room like mine, you end up using only 12' of the ceiling! (25% to 75%). That's only HALF the ceiling! (compared to the entire length of the floor). Think about it. You've got front, side and rear speakers in 7.1 beds (and front wides in 9.1 plus an extra side surround in 11.1) to cover that entire 24' length. Now you want to cover the entire ceiling with only 4 speakers? It won't work! So to get the strong overhead, you cut out half the ceiling to get around it! But add top middle with front heights and you get the FULL 24' length with smooth imaging (not counting the "special" center speaker case, it's then even again! 6 bed and 6 overhead! You now have a helicopter that can circle high or low or anywhere in-between without limits. Using only tops, it can only fly 1/2 the ceiling! That's why I went with 6 overhead. The helicopter sounds pretty much identical at bed level (you can do this shutting off overheads and playing the same demo) and ceiling level here. It circles the ENTIRE 24' room length! That's the way to go, IMO.

We need more AVR/AVPs to support it (unfortunately locked Atmos is a problem; DTS:X Pro will soon solve it for everything else on models supporting 13+ channels).
You might be right about needing six ceiling speakers for a four row theater. However when I researched this for my room the consensus seemed to be that for most domestic situations four ceiling speakers is optimal.

Now unfortunately most domestic spaces are not really optimal for multi channel audio. It really does require a custom built room for optimal results. Few have that opportunity.

Fortunately I have had that luxury to design a room with almost perfect dimension ratios.

The room is 29' long with 9' ceiling.

So I did the layout to Dolby specs. It is 7.2.4. It is a three row 9 seat room.

Now the first row needs to be at least 12' from the screen and front speakers.

That being the case the front Atmos speakers are just in front of the front row, and immediately to the left and right of the outside seats.

The second row of Atmos speakers is in line with the first row, right between the second and third row. That second row is about 6' ahead of the rear backs.

In practice this has worked out well. The results from the Dolby up mixer has been excellent. I have no complaints with movies, they are terrifyingly realistic. I have never localized to an individual speaker. There seems to be an excellent 360 degree sound field with height illusion.

Personally I was highly skeptical of this new technology, but have to admit it works far better then I anticipated. All speakers seem to be a distance apart where a seamless sound field can be created but not so close together that they interfere with each others FR. Form my observation and measurements I can see why another two ceiling speakers might well be a downgrade.

The other issue in the relatively confined domestic situation is the downside of adding more channels. Even the very best systems make a bit of noise. So as you add channels then you downgrade the S/N of the system. So you have 11 audio channels plus the sub/LFE channels. So at a minimum for a system like this you are going to have 13 amp channels. In this system because of active triamping of two speakers and active biamping of three, the number of amp channels is 18.

Anyway you slice it that is a significant outlay on power amps to say the least, to say nothing of the power bill, space required and the design and implementation of the necessary ventilation.

So with the power amps and active crossover on alone, the room is quiet and no improvement in S/N would be required. Add the pre/pro in the mix, and you can just hear noise in a very quiet room. It does not ever intrude in program. However you can see that adding further channels would probably push things over the edge.

So I think for the size of a domestic room we are at the realistic limit now, unless we go to more expensive electronics with improved S/N beyond the weighted 100 db.
That is the S/N of each channel in the pre/pro. The power amps are 105 db unweighted, which is why you do not hear them.

Putting 30 or more speakers in a domestic space is just not sensible or practical on any level. Actually it is daft.

So my view is that 11 audio channels and 2 sub channels works very well indeed for a properly spaced three row cinema. I can see that 13 audio channels might be required for a four row theater. After that you are getting into the realms of professional audio.

I suspect the number of domestic AV rooms of the size of this one is very small and ones greater then 4 rows is likely miniscule.
 
Philnick

Philnick

Enthusiast
TLSGuy: To address your concern about wildly exaggerated surround levels - I'm only talking about a boost of about two decibels in most cases.

Of course our ears will - and should - favor the sound from the front. What I'm saying is that the automatic processing shouldn't artificially reduce the level of the off-axis sound, playing it quieter than intended by the mixing engineer. That's the effect of using an omnidirectional microphone, which hears the mix differently than the mixing engineer, because it doesn't attenuate sound from the rear and above the way our ears do, leading the room correction circuitry to do too much attenuation, distorting the mix.

I don't want exaggeratedly loud surrounds, I just don't want them artificially attenuated.

I'm saying the test tones should be level matched, not that the usually quiet surround sounds should made as loud as the principal sounds. I just don't want them rendered inaudible by an omnidirectional microphone telling the automation that they're louder than we can actually hear them.
 
D

daddyora

Enthusiast
May be the dumb question of today - which speakers are you referring to as "surround" ?
 
TLS Guy

TLS Guy

Audioholic Slumlord
May be the dumb question of today - which speakers are you referring to as "surround" ?
I don't know what Philnick is talking about, but I assume the surrounds and rear backs at least. Anyhow it is nonsense and a 2 db boost is unlikely to upset the apple cart.

One thing I do know, when facing forward you should NEVER be aware of any speakers behind you are above you unless there is an actual instrument or object in the location of that speaker or speakers. If you do, then they are too loud, or too severely miss matched from the fronts.
 
Philnick

Philnick

Enthusiast
By "surrounds" I mean any speaker (other than subwoofers) not part of the front soundstage (left, right and center). The left and right surround speakers may not need to be tweaked if they are in front of the main listening position. Similarly for the top front speakers, which - at the standard 15 degree elevation - should be unmolested by the pinnae.

PS You should not be aware of any of the speakers - just the sound field they all create.
 
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AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
So then in the reproduced sound you want the same balance of forward, side, rear and ceiling sound. Then it will sound realistic, which it does. If you go turning up the rear, side speakers and Heaven knows what else, you HAVE destroyed and violated the natural balance.
Wait, are you saying that people should not manually adjust the sound levels in order to hear the sounds better?

What if the sound mixers don't have all the sounds "balanced"?

What if the dialogue level is too low or the Atmos ceiling sound effect level is too low?
 
TLS Guy

TLS Guy

Audioholic Slumlord
Wait, are you saying that people should not manually adjust the sound levels in order to hear the sounds better?

What if the sound mixers don't have all the sounds "balanced"?

What if the dialogue level is too low or the Atmos ceiling sound effect level is too low?
I'm saying that people can do what ever they want with their rigs.

However setting levels is something by my measurements and calculations is something that Audyssey does get right. It should, as leveling is a very simple program and it would be absurd if it could not do that much.

I can just speak for my rig. I have felt no need to alter any of the Audyssey set levels. I know a lot of people seem to have need to increase the center volume. On my rigs that have had centers, I have not had to do that, and on none of my two rigs here that have center channels. There is zero problem understanding dialog on these systems or the 2.2 system for that matter. All have easily intelligible natural speech.

I suspect this center issue is because most centers are not very good. The center is a very difficult proposition from a design point of view. I think that is why good ones are few.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
I'm saying that people can do what ever they want with their rigs.

However setting levels is something by my measurements and calculations is something that Audyssey does get right. It should, as leveling is a very simple program and it would be absurd if it could not do that much.

I can just speak for my rig. I have felt no need to alter any of the Audyssey set levels. I know a lot of people seem to have need to increase the center volume. On my rigs that have had centers, I have not had to do that, and on none of my two rigs here that have center channels. There is zero problem understanding dialog on these systems or the 2.2 system for that matter. All have easily intelligible natural speech.

I suspect this center issue is because most centers are not very good. The center is a very difficult proposition from a design point of view. I think that is why good ones are few.
Not every source/content (especially digital compressed contents) is created equal in terms of quality.

And if the source isn't great, your speakers aren't going to miraculously improve the sound quality of the contents no matter how great you think your speakers are.

And I'm sure everyone thinks his Revel Salon2, B&W 800D, Linkwitz Orion, RBH SVTRS, Legacy Whisper, Salk SoundScape, etc., sound better than everyone else's. :D
 
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TLS Guy

TLS Guy

Audioholic Slumlord
Not every source/content (especially digital compressed contents) is created equal in terms of quality.

And if the source isn't great, your speakers aren't going to miraculously improve the sound quality of the contents no matter how great you think your speakers are.

And I'm sure everyone thinks his Revel Salon2, B&W 800D, Linkwitz Orion, RBH SVTRS, Legacy Whisper, Salk SoundScape, etc., sound better than everyone else's. :D
Well may be we have been lucky. We have watched BDs, DVD,s Netflix, Amazon prime, Brit player, HBO Prime, YouYube TV from Comcast, the BBC from the UK. Between me and my wife we watch an enormous variety of program material from a wide variety of sources. I have never had to adjust the center channel volume, at our former home and none of the two systems here. Not only that, but when my wife is watching on her system downstairs, I can easily hear every word on the upstairs landing.

I will note however that in other systems I have heard voice clarity from the center channel leaves a lot to be desired as a rule. As I say, I have sweated blood to get the center channels right, and the AV room TL center underwent a number of iterations before I was really happy with it. Now it needs leaving well alone.

DIY rules. Who needs a mega corporation to muck things up!
 
NINaudio

NINaudio

Audioholic Field Marshall
I too have always felt that Audyssey tweaks my surrounds' volumes too low. This is especially noticeable to me when watching the hotel lobby and helicopter rescue scenes in the Matrix where you can hear the bullets whizzing past you and hitting objects behind you.
 
panteragstk

panteragstk

Audioholic Spartan
I too have always felt that Audyssey tweaks my surrounds' volumes too low. This is especially noticeable to me when watching the hotel lobby and helicopter rescue scenes in the Matrix where you can hear the bullets whizzing past you and hitting objects behind you.
That's why after everything is done I bust out the old trusty SPL meter to see where the levels are set. MOST of the time it's spot on, but I've had to make some adjustments here and there to make sure nothing weird happens.
 
AcuDefTechGuy

AcuDefTechGuy

Audioholic Jedi
I too have always felt that Audyssey tweaks my surrounds' volumes too low.
Well, you're either unlucky or your speakers suck, especially when you can't hear much from your Atmos speakers because the sound mixers made the Atmos content levels too low. :D
 
NINaudio

NINaudio

Audioholic Field Marshall
Well, you're either unlucky or your speakers suck, especially when you can't hear much from your Atmos speakers because the sound mixers made the Atmos content levels too low. :D
If I heard anything from my Atmos speakers that would be amazing since I don't have any! :eek: :p
 

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