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post #1 of 20 Old 08-27-2016, 05:03 PM - Thread Starter
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Mixing Atmos

Tim Hoogenakker, re-recording mixer with the Formosa Group, talks about his work on movie and TV soundtracks, including a look at his studio, mixing in Dolby Atmos for commercial and home release (with animated examples of the Atmos panner and metadata modules), upmixing 5.1 and even 2-channel sources to Atmos, restoration of catalog titles, assuring proper downmixing of Atmos to 5.1 or fewer speakers, mixing live-concert titles in Atmos, the difference between Atmos and DTS:X, doing his own final encode, anecdotes from some of the projects he's worked on, answers to chat-room questions, and more.

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post #2 of 20 Old 08-29-2016, 01:47 PM
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I wish we could do like AVS member tours of some of these mixing rooms. That would be so cool to see how it all works and sounds and so on.

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post #3 of 20 Old 09-01-2016, 08:48 AM
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@Scott Wilkinson I have a quick question. Around 26 minutes he discusses Atmos having a bed of up to 7 channel and 2 atmos rows. This sounds like he's saying the multiple atmos speakers are only two channels max as if the same material is fed to all the atmos speaker on the left and the same to the ones on the right...no matter the number of speaker. Any clarification on this?

The way it comes across there's no reason to buy a 4 channel atmos AVR.. or heck a flagship AVR could do 10 Atmos speakers (if they really are just two channels up there) and wides. I suspect that's not what he means but when I watch the video .. that's what he says.

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post #4 of 20 Old 09-01-2016, 01:29 PM
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Thumbs up for the John Wick mix. It's one of the most impressive I've heard.
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post #5 of 20 Old 09-01-2016, 03:21 PM
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I also really enjoyed the John Wick blu-ray mix. Keep up the great work.
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post #6 of 20 Old 09-04-2016, 10:54 PM
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Thank you, Scott and Tim Hoogenakker, for this informative video about mixing for home use.

cdy2179 had a very important question... Besides all the other ideas regarding the mixing results; theatrical print-master for blu-disc yes/no, SPL drop to 80-81 dB (Sony, Brian Vessa even 75 dB), tweaking the track here and there, EQ yes/no, x-curve yes/no, nearfield 80 Hz mixing, etc. etc.... The truth is that there is just not enough room in this home 3D space to move this objects... Second problem, what I heard, was that this ceiling channels are not discrete!... Someone even said in a other forum that the ceiling channels are comparable to mp3
...here we go again...

Before any comments I recommend to read this tread. It is very very informative because studio mixers and sound departments are among here https://www.avsforum.com/forum/138-av...l#post46545057
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post #7 of 20 Old 09-05-2016, 12:06 AM
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Hi all,
Thank you for the great responses!
Re: The kind words regarding John Wick, giving credit where credit is due, it was the original sound crew that made it so awesome to begin with. Mark Stoeckinger and crew helped us make it fall into place for Atmos. I agree, it turned out very cool indeed.

Re: questions, first from @cdy 217:

Quote:
Originally Posted by cdy2179 View Post
@Scott Wilkinson I have a quick question. Around 26 minutes he discusses Atmos having a bed of up to 7 channel and 2 atmos rows. This sounds like he's saying the multiple atmos speakers are only two channels max as if the same material is fed to all the atmos speaker on the left and the same to the ones on the right...no matter the number of speaker.
That’s an excellent question I should’ve clarified better. (there’s SO much to cover in the show within 1 hour, I really could only briefly glance over certain topics. @Scott Wilkinson and I wanted to cover a lot of area as best as possible given the timeframe.)

Nope, it’s definitely not two channels max at all by any means. Those ceiling channels are indeed discrete.
The heights/overheads path is just “another” path to get to the tops. Usually that particular path is to get elements to the top to specifically cover a broader range area..
but it’s the 118 objects that can be panned to any speaker or combination of speakers to create space. (ceiling, sides, front, wherever..), that is where it gets very discrete.
so, for example, if I placed a helicopter sound on an object in the front top left and pan across the speakers to the back top left, then crossing over to the rear top right, you’ll definitely have a very distinct separated pan across the top - so if you have 4 above, you’ll hear that discrete effect, and additionally, if you have even more channels for your top speakers, you’ll have that much more of distinct separation and smoother movement because it’s object-based.
(no, not trying to “sell people more speakers”, it’s just the architecture of it, and it works pretty well.)

I’ve done some mixes where I’ll have a few things in the 7.1 bed, but with my full 118 objects filling in different upper speakers in various degrees. (no “overhead” path at all). As I said, it’s just another way of getting there. It’s super flexible.

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there is just not enough room in this home 3D space to move this objects... Second problem, what I heard, was that this ceiling channels are not discrete!... Someone even said in a other forum that the ceiling channels are comparable to mp3
Great question @OBJECT , as I mention above, you’ll find the ceiling channels are definitely discrete. I’m not sure how a rumor started that the ceiling channels are like an MP3, rest assured, that’s not accurate. Dolby is very good about not cheesing out on that kind of thing.

Oh, and someone had asked on another forum if I've done Auro 3D. This answer is nope.
Dolby Atmos and DTS:X are results of what my clients ask for. None of them have inquired about Auro (yet), but I'll be interested in hearing it myself if the opportunity arises.

Thanks again all, I really hope this helps explain things as I know that Atmos is a very very in-depth topic. I don’t get on here very much, but I try to pipe in now and then.

Cheers,
- Tim
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post #8 of 20 Old 09-07-2016, 06:10 AM
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Originally Posted by thoogenakker View Post
Hi all,
Thank you for the great responses!
Re: The kind words regarding John Wick, giving credit where credit is due, it was the original sound crew that made it so awesome to begin with. Mark Stoeckinger and crew helped us make it fall into place for Atmos. I agree, it turned out very cool indeed.

Re: questions, first from @cdy 217:


That’s an excellent question I should’ve clarified better. (there’s SO much to cover in the show within 1 hour, I really could only briefly glance over certain topics. @Scott Wilkinson and I wanted to cover a lot of area as best as possible given the timeframe.)

Nope, it’s definitely not two channels max at all by any means. Those ceiling channels are indeed discrete.
The heights/overheads path is just “another” path to get to the tops. Usually that particular path is to get elements to the top to specifically cover a broader range area..
but it’s the 118 objects that can be panned to any speaker or combination of speakers to create space. (ceiling, sides, front, wherever..), that is where it gets very discrete.
so, for example, if I placed a helicopter sound on an object in the front top left and pan across the speakers to the back top left, then crossing over to the rear top right, you’ll definitely have a very distinct separated pan across the top - so if you have 4 above, you’ll hear that discrete effect, and additionally, if you have even more channels for your top speakers, you’ll have that much more of distinct separation and smoother movement because it’s object-based.
(no, not trying to “sell people more speakers”, it’s just the architecture of it, and it works pretty well.)

I’ve done some mixes where I’ll have a few things in the 7.1 bed, but with my full 118 objects filling in different upper speakers in various degrees. (no “overhead” path at all). As I said, it’s just another way of getting there. It’s super flexible.



Great question @OBJECT , as I mention above, you’ll find the ceiling channels are definitely discrete. I’m not sure how a rumor started that the ceiling channels are like an MP3, rest assured, that’s not accurate. Dolby is very good about not cheesing out on that kind of thing.

Oh, and someone had asked on another forum if I've done Auro 3D. This answer is nope.
Dolby Atmos and DTS:X are results of what my clients ask for. None of them have inquired about Auro (yet), but I'll be interested in hearing it myself if the opportunity arises.

Thanks again all, I really hope this helps explain things as I know that Atmos is a very very in-depth topic. I don’t get on here very much, but I try to pipe in now and then.

Cheers,
- Tim
Tim, thanks for clearing it out! I suppose we do, I definitely do, appreciate very much that you can spear some time with us.
Do you mind if I speak freely and open...
When you said "it’s definitely not two channels max at all by any means. Those ceiling channels are indeed discrete." " very discrete"

We have discrete channels for left channel, center channel, right channel, Ls, Cs, Rs. This are from the encoder point of view and they are discrete channels by meaning mixing for certain speaker location.

What is Object then?
I think object is one sound object among other sound objects (2 object, 3 object, 4 object, etc.)... Which you are moving in a box, so called 3D space... Have I understood correctly, you are not moving this objects because of channel speakers. You are moving this sound objects just inside a written m2 box and not per speaker channel location.
When you use the Dolbys Atmos rendering software - do you first specify the room size, or specify your room size or cinema room size, before mixing home size?
Aka the bigger the room 3D space is the more headroom you have for moving this objects (?)

Many are confused about discrete channel panning vs. object panning... This comes to a point, that certain people are thinking when they go to the speaker store to by speakers they are actually thinking of buying channels!
Speaker manufacturers are also confused about this, should we sell channel speaker location or what... I even occasionally fall for it, because the money wallet says so. 1, 2 or 4 ceiling speakers.
I still believe that 4 ceiling speakers (vs. Cinema 20) are just not enough to move all this numbered objects inside our universal home theater box.

Do you mix or sound check the home track via a high-end pre-pro and a consumer AVR to sound check the result through the decoder? This is what Mi Casa did with all and the result was stunning.

According to Dolby the ceiling speaker output is limited in frequency response starting from 100 Hz? What is it in Cinemas? Ls, Cs and Rs can be mixed full range.

Now to the main subject... Who was it who invented that there is not enough space in a blu-disc to include the untouched theatrical print-master track? Why are you not including it?, if you have the power to do it (?)... Why not include in every blu-disc 3 audio tracks; late night +headphone +theatrical?
We with dedicated home cinema 3D space, we want the theatrical print-master untouched track on every blu-disc!
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post #9 of 20 Old 09-09-2016, 04:20 PM
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I think there's a is a lot of confusion here because of how Dolby markets Atmos at home vs. the interface used by re-recording mixers like Tim, vs. the technical reality of how it's actually implemented. Is is a mathematical fact that theatrical Atmos and home Atmos cannot work identically. The BD format and HDMI standard do not provide enough bandwidth to allow a full theatrical Atmos track to fit without resorting to lossy compression. Even then, I believe the best that can be done to ensure compatibility is a 7.1 audio track and a separate meta-data stream.

AIUI, when a Dolby Atmos track is put on a BD, it is mixed down to 7.1 channels plus a meta-data stream. The meta-data stream describes the objects locations but not their content, which is entirely contained in the 7.1 channels. The home Dolby Atmos renderer uses this meta-data to lift a full Atmos mix (9.1 beds + objects) out of the 7.1 mix. Dolby calls this round-trip process "spatial encoding / spatial decoding", and it is closely related to how Dolby handles down-mixing and up-mixing of 5.1 and 7.1 content to/from stereo as well as up-mixing of non-Atmos content to Atmos via "Dolby Surround".

However, there is a *big* difference. With Dolby PL/PL2/PL2x/PL2z/Surround, there is no meta-data to tell the up-mixer how to steer content from 7.1 or fewer channels of sound to the speakers in use, so the up-mixer has to rely on educated guesses. With the meta-data in an Atmos home mix, the decoder is able to lift a fully discrete object-based mix (albeit one not exactly the same as what was input) from the 7.1 content. This up-mix is much more true to the original than what could be achieved without the meta-data. Furthermore, by monitoring the track on a home-compatible Dolby Atmos system a re-recording mixer like Tim Hoogenakker can make adjustments as needed to compensate for any deficiencies that arise in the spatial-encoding/decoding process.

Tim or someone else who knows better, please correct me if I got any of these details wrong, or if you have more to add. I do wish Dolby did a better job of clarifying exactly how their technology works, because I think what they have done is very good considering the technical limitations they have to work with. Furthermore, many of us do understand the math and know that Dolby had to compromise *somewhere*. It would certainly help to dispel rumors like "objects are encoded as MP3s" and what not.

=====================

On another note, I'd like to suggest a correction to the discussion in the video on playback levels. Particularly, the "85 dBC" vs. "80 or 81 dBC" vs. "75 dBC" *do not* refer to average SPL of content during playback. These levels are actually on the loud side for typical content, but a lot depends on tonal balance as well. For example, FX with a lot of bass will be a lot higher in dBC for the same loudness.

Instead, they refer to the average level measured while a standardized pink noise sample is played through each speaker for calibration. The usual standard is -20 dBFS of pink noise, often band-limited to 500-2000 Hz. The relevance of this is that tracks mixed on a dub stage calibrated to 85 dBC tend to sound too loud when played in a smaller residential-sized room calibrated to the same level and a decrease in playback level (or equivalently, calibration level) is necessary to achieve a good loudness match. I like to call this the "room appropriate playback level", and it depends in a complicated way on room size, seating distance, room treatment, speaker radiation pattern, tonal balance, and possibly other variables. Typical small-room appropriate calibration levels fall in the range of 79-82 dBC, but may be a lot lower in some circumstances.
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post #10 of 20 Old 09-09-2016, 04:40 PM
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Quote:
Originally Posted by Daniel Chaves View Post
I wish we could do like AVS member tours of some of these mixing rooms. That would be so cool to see how it all works and sounds and so on.
I also think this would be really cool and would like to see it go the other way too. I'd like for industry pros to tour some of the truly high-end playback systems some people on this forum have in their homes, particularly the DIY built systems.
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post #11 of 20 Old 09-09-2016, 07:08 PM
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Tim or someone else who knows better, please correct me if I got any of these details wrong, or if you have more to add.
The home version of Atmos is delivered using TrueHD lossless packing. The TrueHD bitstream is made up of substreams. The first substream contains the entire soundtrack as a 2-channel mix. The second substream contains only the audio & instructions (data & metadata) that, when combined with the first substream, will reconstitute the 5.1 mix. The third substream contains just the data & metadata that, when combined with the first two substreams, will reconstruct the 7.1 mix. And so on with additional substreams allowing for 9.1, 11.1, etc. Keep in mind that at every step you end up with a lossless bit-for-bit copy of the studio masters for the 2.0, 5.1 and 7.1 mixes.

One handy thing about this structure is that it allows TV manufacturers to license just the 2-channel decoder. Why pay for full Atmos decoding and waste valuable DSP resources to unpack the entire Atmos soundtrack only to downmix it back to 2 channels when there already is a 2-channel mix nested inside every Atmos track? Same with 5.1 HTiBs and 7.1 AVRs; no need to decode all the substreams, just the first two or three.

In the case of Atmos soundtracks, the fourth substream wasn't use to expand 7.1 to 9.1 but instead to losslessly pack audio objects. Which means that Atmos decoders will unpack all four substreams. Problem is, the audio in the objects is also in the 7.1 downmix. So, part of the decoding process has each object inverted out of phase and sent as a cancellation signal to the 7.1 downmix. Once those sounds are sliced out of the downmix, you've recovered the bed channels of the original Atmos mix. During encoding: channels + objects = downmix. Atmos decoding just reverses that process: downmix - objects = channels.

Quote:
Dolby calls this round-trip process "spatial encoding / spatial decoding", and it is closely related to how Dolby handles down-mixing and up-mixing of 5.1 and 7.1 content to/from stereo as well as up-mixing of non-Atmos content to Atmos via "Dolby Surround".
Spatial coding is not the above encode/decode steps nor does it have anything to do with Dolby Surround upmixing. Instead it is simply the combining of objects. The home Atmos encoder defaults to 12 objects, though it can be dialed up 16 or 20 objects (I forget what the max number is) if storage space is available on the disc. If the theatrical soundtrack has that number of objects or less at any given moment, then each object in the theatrical Atmos soundtrack is encoded as an individual object in the home Atmos track.

However, if there are moments in the theatrical soundtrack where the number of objects exceeds the number you've allotted for the home track, then nearby objects are combined to stay within the allotted number. It's the logical compromise since those sounds were coming from the same general direction anyway. That's spatial coding. And those combined objects don't get pried apart during playback; i.e., there's no "spatial encoding" and "spatial decoding".
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post #12 of 20 Old 09-10-2016, 12:31 AM
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Thanks for the wonderful clarification. So if I understand you right, the compromise Dolby chose to deal with the bandwidth and storage limitations of BDs was to reduce the number of available objects and to use spatial coding to fold a larger ensemble of objects into the reduced number. This seems like it should work well enough. After all, how many people can independently track 12 objects at the same time anyway?

I'm still a bit of an "Atmos at home" skeptic though. I totally get that Atmos is a big boon to the content producers who can create immersive content with much greater ease. I also think it's a big plus in a cinema where it can provide a 3D immersive experience with coverage over a wide area. Still, I find listening to my 5.1 system at home to be more immersive than the local Atmos cinema. The only thing the cinema does better is the discrete overheads, but I find the overhead cues synthesized in 5.1/7.1 down-mixes of Atmos tracks to still be convincing a lot of the time. My front stage images much better. Also, and maybe this is just an issue with my local cinema, but ambient sounds really suck at the cinema. It sounds like a bunch of speakers are on the wall playing at me. At home, I experience strong envelopment with ambient sounds, and I'm not even using dipoles for my surrounds. I'm actually using horns. I do have diffusers installed, which I believe helps immensely with this. But anyway, I'll take the superior front stage imaging and surround envelopment over the overheads at my local cinema any day.
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post #13 of 20 Old 09-10-2016, 10:34 AM
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Originally Posted by awediophile View Post
So if I understand you right, the compromise Dolby chose to deal with the bandwidth and storage limitations of BDs was to reduce the number of available objects and to use spatial coding to fold a larger ensemble of objects into the reduced number.
Exactly. Again, they only resort to spatial coding IF they run out of objects.
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I'm still a bit of an "Atmos at home" skeptic though. ...I find listening to my 5.1 system at home to be more immersive than the local Atmos cinema. ...I find the overhead cues synthesized in 5.1/7.1 down-mixes of Atmos tracks to still be convincing a lot of the time.
Impressive that you can get array-like immersion and convincing imaging at your sides and behind you and above you using only 2 surround speakers. Most of us aren't that fortunate and have to use separate pairs of speakers at each of those locations.

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post #14 of 20 Old 09-17-2016, 12:00 PM
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Again many thanks for clearing all out!


definitely not two channels max at all by any means... so if you have 4 above, you’ll hear that discrete effect, and additionally, if you have even more channels for your top speakers, you’ll have that much more of distinct separation and smoother movement because it’s object-based. ”
...if you have even more channels - this is the hole truth behind what Atmos is meant for!


Dolbys spec paper http://www.dolby.com/us/en/technolog...guidelines.pdf says on page 3, even 24 speakers on floor and 10 overhead. As you can see both rooms are identical in size
They are saying that 4 ceiling speakers are the best option...but where did they forget the 24/10?
Who is having 24/10 (34 speakers) in a blu mix room and in a home environment? I suppose Tims room do not have it for blu purpose (?), but what about the Dolbys and DTSX home mix rooms? John Wick was mixed in a Dolby room.


From here it came to my mind... ”It’s super flexible ”... Yeah, 24/10... A lot of end-users are concerned about the flaws the movie studio/mixers are doing in the near-field mixing... I would like to see a 24/10 system in near-field use From this perspective, is near-field mixing even necessary?


Everybody can count how many speakers they can afford precisely of same class for all channels even for overheads (same tweeters/bass drivers/box) But what about the main issue, best possible object moving (12 objects, 16 or 20) vs. room size vs. amount of speakers with proper measured distances between this front & surround & overhead speakers vs. the result a maximum 24/10 can provide?
I haven't seen so far any Dolby produced spec paper about different room size vs. different amount of speaker system...have you?
I believe this question has everything to do with how to move this objects properly enough in a 3D home space. The bigger the 3D space is the more headroom you have for moving this objects.
But at a moment I do not have on my hand proper speaker placement manual to certain room size.


If I would be a mixer, I would re-check the tracks through a popular consumer high-end pre-pro... The decoder in it is just one part of everything else.


Is is a mathematical fact that theatrical Atmos and home Atmos cannot work identically. ” … Did you mean there is not enough band-with for a untouched theatrical track?


I wish we could do like AVS member tours of some of these mixing rooms. ” ...But they will not allow it to happen, because they think that they have some rocket science in their studio room not allowing others to see it – for your eyes only


To sduranis last... What would be a universal size home listening room? Would approx 3 m with and 4 m long be appropriate? I would rather point out that it is a waste of money by installing a Atmos system in this sized room. I would rather say that 6 surround speakers sound much better and it is cheaper and easier to install...anyone test it?


One question came up... Why are the surround speakers installed up on the walls in the cinema mix stage, in a home mix studio (aka Tims) and even at Dolbys own rooms... Meanwhile the Dolby home spec paper are saying that the home speaker setup should be ITU-R meaning surrounds in same high with the front stage max. 1.2 times higher than front. Shouldn't the surrounds be in exactly the same position at home like you mixers have in the studios to maintain exactly the same pan? Specially with Atmos?


Many thanks to all!
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post #15 of 20 Old 09-17-2016, 01:04 PM
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To sduranis last... What would be a universal size home listening room? Would approx 3 m with and 4 m long be appropriate? I would rather point out that it is a waste of money by installing a Atmos system in this sized room.
If room size prevents you from hearing height differences, then it would be a waste of money for you. But for anyone that can hear the difference between sounds at their sides vs sounds behind them vs sounds above them, it's not a waste to install a 7.1.4 Atmos setup, even in a 3m x 4m room.
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post #16 of 20 Old 09-18-2016, 05:32 AM
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Problem is, the audio in the objects is also in the 7.1 downmix. So, part of the decoding process has each object inverted out of phase and sent as a cancellation signal to the 7.1 downmix. Once those sounds are sliced out of the downmix, you've recovered the bed channels of the original Atmos mix. During encoding: channels + objects = downmix. Atmos decoding just reverses that process: downmix - objects = channels.
Thanks very much for this explanation. That seemed to me to be the only plausible way it could be done (while also preserving compatibility between old and new decoders), but this is the first time I've seen it confirmed in such a clear way.
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post #17 of 20 Old 09-18-2016, 06:10 AM
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What would be a universal size home listening room?
I admit to being confused by the question. Is there such a thing? Should there be? My impression has been that they come in all shapes and sizes.

Quote:
Would approx 3 m with and 4 m long be appropriate? I would rather point out that it is a waste of money by installing a Atmos system in this sized room.
Is the reason you feel this way because you don't think that a 130 sq-ft height layer is an adequate sound surface, or what? While a 10x13' room is on the small side, that seems more than adequate to me to locate L/R/F/B sounds overhead. I'm planning on doing precisely that this fall, in a room not too much larger (~12x13.5').

Now if you're talking about a closet, then probably only 1 height speaker would be useful. But 2-pair of overhead channels would provide discriminable positioning on both axes, even in relatively small rooms. And as the size expands, first top-mids would make sense... and eventually expanding to the 4th or 5th height pair.

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I would rather say that 6 surround speakers sound much better and it is cheaper and easier to install...anyone test it?
6 surround speakers? Where are you advocating locating the extra pair beyond the sides and rears? Front wides? What advantage would it offer to expand the ground level further of a smaller space you already feel is inadequate for any height layer?

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Why are the surround speakers installed up on the walls in the cinema mix stage, in a home mix studio (aka Tims) and even at Dolbys own rooms... Meanwhile the Dolby home spec paper are saying that the home speaker setup should be ITU-R meaning surrounds in same high with the front stage max. 1.2 times higher than front. Shouldn't the surrounds be in exactly the same position at home like you mixers have in the studios to maintain exactly the same pan? Specially with Atmos?
If this is actually the case, then I'd be interested in that as well. (Well I already understand it in the cinema mix stage... different context [cinemas don't have 8-9' ceilings].) And the reason for the ITU-R ear-level recommendation in the home is to maximize the separation between the heights and the surrounds. The previously recommended surround heights predated the availability of any discrete height speakers in the ceiling. But the home mix studio would seem to call for different handling, as you've suggested.

Last edited by VideoGrabber; 09-18-2016 at 06:22 AM. Reason: typos
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post #18 of 20 Old 09-19-2016, 07:05 AM
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How big room do you prefer for 24/10 speaker system?
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post #19 of 20 Old 09-24-2016, 02:06 AM
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post #20 of 20 Old 05-27-2017, 01:02 PM
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This was an extremely informative forum topic. Thanks to all that participated. I learned much useful knowledge. I'm using 7.2.4 Atmos set up and I love it. I'm using bounce technology. Some critics claim that bouncing off of the ceiling isn't very good but, I disagree. After I set up using Audyssey. I never know if I'm spelling that correctly. After set up, I tweak the height channels by ear. Once I dial it in the height effects are spectacular for our cinema. I'm using Martin/Logan height speakers, on the upper end of current offerings. I'm considering trying the new SVS height effect speakers. They're priced affordable so, not as painful as some of the other upgrades we've done in the last 13 months to modernize our cinema. I love the flexibility that DTS X Master allows. I was ecstatic with the audio mix of the new 4k UHD versions of Harry Potter. Can't wait for the first four movies to be released. It was the DTS X Master remix, that made this content upgrade a clear winner for our home cinema. I wish there were extended versions of all eight of these spectacular films. Again, thanks to all who participated. Home cinema is the healthiest drug I've ever abused to escape reality.
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