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post #61 of 1315 Old 04-25-2012, 01:37 PM
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Originally Posted by Roger Dressler View Post

Sorry to disappoint, but that [dolby and dts duke it out!] war will not likely repeat. DTS is no longer in the cinema hardware business, having sold it to Datasat.

What SRS is promoting is a common content creation format called MDA (multi-dimensional audio) which is an open standard format for creating object-based audio and associated metadata. This would be used at the productions stage level, and the finished MDA mix could then be encoded for any desired playback hardware, be it Atmos, Auro3D, IOSONO, IMM, or even NHK 22.2.

The main reason each of these companies currently has their own proprietary production tool is because there is no universal standard yet implemented in the DAWs and DFCs used in film production. That standard could be MDA as it is not associated with any company's cinema processor platform. Since it is unlikely that the film studios will be willing to mix their movies multiple times, the need for a universal production system is obvious.

However, DTS's acquisition of SRS, including their MDA technology, does suggest that DTS intends to be a major player in the theatrical 3D audio mix biz, which translates to influence over industry standards for the format of DAW deliverables . . . and the more intimate DTS's knowledge|control over the format of soundtrack stems, the better DTS will be positioned to deliver a future HT 3D audio technology in competition with "home Atmos".

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post #62 of 1315 Old 04-25-2012, 01:53 PM
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Originally Posted by SoundChex View Post

with "home Atmos".

Hmmm...maybe it will be called "Atmosh", or maybe "HAtmos".



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post #63 of 1315 Old 04-25-2012, 01:53 PM
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Originally Posted by Gary J View Post

Yes after surround sound, Room EQ and lossless there is not much left to sell besides more speakers.

Why do you keep repeating that? Breaking up traditional audio channels into streams with spatial metadata allows new (and forgotten) renderers that use less speakers, e.g. Ambisonics with only 4 speakers.

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post #64 of 1315 Old 04-25-2012, 02:00 PM
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Originally Posted by markus767 View Post

Why do you keep repeating that? Breaking up channels into streams and positional data allows new (and forgotten) renderers that will use less speakers, e.g. Ambisonics with only 4 speakers.

Did you notice what I quoted? "I could see a very convincing image with just 6 surround wall speakers and 4 on the ceiling along with the normal 3.1 up front."

That is promoting 14 speakers by my count.
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post #65 of 1315 Old 04-25-2012, 02:26 PM
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Originally Posted by Gary J View Post

Did you notice what I quoted? "I could see a very convincing image with just 6 surround wall speakers and 4 on the ceiling along with the normal 3.1 up front."

That is promoting 14 speakers by my count.

That's just one possible (very uninspired) renderer. People need to stop thinking in channels or speakers but in (re-)creating a wave field. Did I mention Ambisonic yet

P.S. http://www.audiosignal.co.uk/Gerzon%20archive.html

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post #66 of 1315 Old 04-25-2012, 02:30 PM
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Originally Posted by markus767 View Post

That's just one possible (very uninspired) renderer.

But the one I responded to. Please make you own point separately.
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post #67 of 1315 Old 04-25-2012, 02:47 PM
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Originally Posted by GXMnow View Post

In a small room, like a home theatre size, I could see a very convincing image with just 6 surround wall speakers and 4 on the ceiling along with the normal 3.1 up front.

Unsurprisingly, you have just described a superset of the DTS Neo:X 9.1 Wide and Auro-3D 9.1 speaker configurations . . . which would also accommodate (full) Yamaha CinemaDSP 11.1 and Audyssey DSX 11.1 play back.

[Ok, now that we've settled on the HT speaker|amp requirements, how soon can we expect the first CE decoders and at-home movie content? ]

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post #68 of 1315 Old 04-25-2012, 03:10 PM - Thread Starter
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Originally Posted by markus767 View Post

Certainly would be an improvement because it could force bass management into the content creation process. This could result in better translation to different types of rooms.

We can only hope!

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post #69 of 1315 Old 04-25-2012, 03:21 PM - Thread Starter
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Originally Posted by SoundChex View Post

I wonder if premium cinemas will translate into premium priced seats...?

It might. But maybe not in the long term. Let's compare with 3D: When a cinema does a 3D presentation, they have to 1) support a separate screen showing the 2D presentation, and 2) the cost of glasses has to be covered. Running costs are higher on both counts, so ticket prices need to be increased.

Contrast that with Atmos: No one would likely opt for the 5.1 rendition, so no need to run on dual screens, and no ongoing cost (like glasses). Running costs are the same as conventional presentations.

In either case, of course, there were fixed capital costs, like silver screens, special projectors, more speakers/amps, new processors, but once those are out of the equation, the value propositions are different.

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post #70 of 1315 Old 04-25-2012, 03:26 PM - Thread Starter
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Quote:
Originally Posted by SoundChex View Post

However, DTS's acquisition of SRS, including their MDA technology, does suggest that DTS intends to be a major player in the theatrical 3D audio mix biz, which translates to influence over industry standards for the format of DAW deliverables . . . and the more intimate DTS's knowledge|control over the format of soundtrack stems, the better DTS will be positioned to deliver a future HT 3D audio technology in competition with "home Atmos".

I totally agree. But that's not a format war, is all I'm saying.

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post #71 of 1315 Old 04-25-2012, 03:39 PM - Thread Starter
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Quote:
Originally Posted by GXMnow View Post

The number of speaker channels needed to make it work is not a fixed quanity. In a small room, like a home theatre size, I could see a very convincing image with just 6 surround wall speakers and 4 on the ceiling along with the normal 3.1 up front. As the room gets bigger, you do need more speakers to produce smooth pans. The white paper mentions 30 degree angle change from speaker to speaker. That works out to a ring of 12 to make it very smooth.

Yes, the addition of wides could be a useful way to anchor offscreen cues in a well equipped home theater. But these are much less essential than the 4 height speakers, so a 7.1+4 = 11.1 kit would be a very compelling solution.

Having said that, I want to amplify on Marcus' point that a variety of interesting rendering technologies can be brought to bear to create the illusion of 3D sound when fewer speakers are available (that means down to 2 speakers or even headphones). These rendering techniques will work better because they will have direct access to the sounds in isolation, and explicit knowledge of where the sound was intended to be, rather than using blind upmixing to infer that information for extracted sounds with less than optimal separation. I find the whole prospect very exciting.

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post #72 of 1315 Old 04-25-2012, 04:12 PM
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Quote:
Originally Posted by Roger Dressler View Post

But these are much less essential than the 4 height speakers, so a 7.1+4 = 11.1 kit would be a very compelling solution.

Indeed, 7.1 plus 4 heights was the 11.1 layout that the inventor of DTS Neo:X (James Johnston) preferred, despite his (former) employer choosing to go 11.1 with 2 heights and 2 wides.

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post #73 of 1315 Old 04-25-2012, 04:20 PM
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Why do you keep repeating that?

What difference does it make. There's always been someone repeating that when we went from mono to stereo and stereo to surround.

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post #74 of 1315 Old 04-25-2012, 04:45 PM
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[quote=Originally Posted by markus767
Certainly would be an improvement because it could force bass management into the content creation process. This could result in better translation to different types of rooms.[/QUOTE]

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Originally Posted by Roger Dressler View Post

We can only hope!

I do not really agree with this. I think the idea of bass management is not well understood.

Current Cinema 5.1 (7.1, etc.) actually does FORCE the creator to do the bass management in the mixing room. The LFE track is completely separate, and that is all that will come out of the subwoofer. There are some smaller speaker systems, and some DSP x-overs and such that can bass manage, but if I am setting one up I usually turn it off unless the main fronts just can't do it. Low frequency sounds are LESS able to be localized, but certainly not impossible. If the screen speakers are just too wimpy to go below 40 Hz, ok we may have to help them out. The screen speakers should be powerful enough in a cinema to do the job. Surrounds are a crap shoot though. The current spec does list 20-20K but in reality, most surrounds do roll off somewhere between 40 and 60 Hz. But when used in an array of 8 though, they do couple together and go lower, so even there, it is rare to bass manage in 5.1 or 7.1

Bass managing the main front speakers is still not what I recomend. The acoustic mix of correlated sounds from 2 screen speakers will result in a 3 db bump in level. But if you electrically add those, you get a full 6 db bump up. This can be compensated for to some degree, but it is never as good as having true full range speakers.

Having a system bass manage on playback is actually taking away a little control from the content creator. If you dump everything below 80 Hz into a common sub, you now have mono below 80 Hz. Can you tell where 60 Hz hum comes from? Maybe the director had a buzzing power line in the room somewhere?? This is an extreme case, but I hope you get where I am coming from. Bass management becomes a necesary evil in some cases.
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post #75 of 1315 Old 04-25-2012, 05:04 PM
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Originally Posted by sdurani View Post

What difference does it make. There's always been someone repeating that when we went from mono to stereo and stereo to surround.

How would you rank changes in impact?

1 -> 2 speakers
2 -> 5
5 -> 13

I see diminishing returns in cost/benefit in that order. Do not construe that to mean that I think such evolution should not happen. Just that is less necessary. Of course I can see that as an unpopular notion among enthusiasts.
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post #76 of 1315 Old 04-25-2012, 05:33 PM
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Quote:
Originally Posted by Gary J View Post

Do not construe that to mean that I think such evolution should not happen. Just that is less necessary.

Necessary for what?
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Of course I can see that as an unpopular notion among enthusiasts.

My point wasn't about the number of speakers but the motive you assign for inventing newer technologies that can take advantage of more speakers.
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Another industry attempt to sell more speakers.

At best, you're projecting.

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post #77 of 1315 Old 04-25-2012, 06:13 PM - Thread Starter
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Quote:
Originally Posted by GXMnow View Post

I think the idea of bass management is not well understood.

Perhaps not, but this does not apply to Marcus or me, if I may so state.

Quote:


Current Cinema 5.1 (7.1, etc.) actually does FORCE the creator to do the bass management in the mixing room. The LFE track is completely separate, and that is all that will come out of the subwoofer on all Dolby cinema processors. There are some smaller speaker systems, and some DSP x-overs and such that can bass manage, but if I am setting one up I usually turn it off unless the main fronts just can't do it.

The problem is that the mains cannot do it. The speakers routinely used in dubbing stages and commercial theaters (and Dolby's own in-house presentation rooms) roll off around 40 Hz, maybe 30 Hz if lucky*. That leaves a whole octave of the main channels unheard. Until we get those soundtracks at home, that is.

*There are dubbing stages that can do better than that, such as Todd-AO, but they are the exception.

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If the screen speakers are just too wimpy to go below 40 Hz, ok we may have to help them out. The screen speakers should be powerful enough in a cinema to do the job.

It's not a matter of power, but response rolloff. How do we help them when they are not designed to do it? Do you EQ them to flat to 20 Hz? I would doubt it.

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Surrounds are a crap shoot though. The current spec does list 20-20K but in reality, most surrounds do roll off somewhere between 40 and 60 Hz. But when used in an array of 8 though, they do couple together and go lower, so even there, it is rare to bass manage in 5.1 or 7.1

And that's fine. If a mixer wants a massive tank to roll front to back and rumble all the way, he will do the manual bass management dance and put the rumble into the LFE.

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Bass managing the main front speakers is still not recommended. The acoustic mix of correlated sounds from 2 screen speakers will result in a 3 db bump in level. But if you electrically add those, you get a full 6 db bump up. This can be compensated for to some degree, but it is never as good as having true full range speakers.

Then maybe they should do that. But as a) they don't, and b) we have shown over these past 20+ years that bass management does work effectively (I personally demonstrated it during the occasion of Delos release party for John Eargle's 1812 Surround Spectacular DVD at Dolby SF -- imagine playing this 5.0 recording with canons blazing and no subs!), it is a valid way to allow mixers and cinema patrons to join the ranks of those hearing the full spectrum of every track of the source content.

Quote:


Having a system bass manage on playback is actually taking away a little control from the content creator. If you dump everything below 80 Hz into a common sub, you now have mono below 80 Hz. Can you tell where 60 Hz hum comes from?

No, which is the same result as with full range speakers. And by the way, who said the crossover had to be 80 Hz? Make it 40 Hz if that's where the speakers poop out.

Quote:


Maybe the director had a buzzing power line in the room somewhere?? This is an extreme case, but I hope you get where I am coming from. Bass management becomes a necessary evil in some cases.

I get where the buzz is coming from, because the localizable harmonics of the buzz from 120 Hz on up are playing from the main speakers, not the sub.

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post #78 of 1315 Old 04-25-2012, 06:27 PM
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I suspect that the 75%+ of Americans who listen to their TV|video audio though the TV set's built in speakers will continue to do so even when DolbyHomeAtmos appears as an audio track encoded on the next-generation-BD they are watching, they are after all already ignoring the majority of the benefits offered by the DD5.1 and TrueHD soundtracks in OTA|cable TV, DVD, and BD. And few among the remaining 25% (who do find added value in DD5.1 or TrueHD) will likely be willing to add 'several' speaker pairs in order to 'fully appreciate' the extra SQ available from DolbyHomeAtmos. So one strategy to wider exploitation of DolbyHomeAtmos might be rethinking what sound quality enhancement technology can be delivered through speakers built into the TV chassis:

For example, (if I understand correctly) this recent ITU demonstration of NHK's UHDTV system on an 85-inch LCD screen reproduced the 22.2 multichannel sound component of the program through a frontal loudspeaker array frame, integrated with the LCD display, which used 102 loudspeaker units with 'sound projector style' DSP in order to reproduce all the appropriate surround sound.


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post #79 of 1315 Old 04-26-2012, 12:32 AM
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I just wanted to coment on some of Roger's last post about bass management here. I am sorry this got far longer than intended. I hope you read it as intended. This is not about DOLBY ATMOS, as I feel it applies to any multi channel sound system. All my opinion from 30+ years of tuning rooms, your feelings and experience may differ.

Carefully used Bass Management can certainly work very well. The problems we run into are very inconsistent quality of sub woofers with wildly varying amount of distortion and even frequency range.

The older IMAX film format was actually a 6.0 system with all 6 channels bass summed into a common hue sub woofer with about 10 db on in band gain. So if you fed any of the 6 channels with flat pink noise, you would measure pretty close to X-curve from 16K down to around 100 Hz or so, but from there down, it would ramp up to + 10 below 80 HZ from the common sub. Play correlated noise into 4 channels now and the electrical summing makes the low end go to more than +20 db while the mid range is at just +6. But for IMAX mixes this worked just fine because they were mixing the tracks knowing this was the room they were going into. But if you take a 5.1 mix into an IMAX room, it turns into a pile of monster bass. And here is the problem. Noone is mixing in a room with bass management like that for normal cinema. On that 1812 Overture recording you talked about.. are the canon blasts mic'd with 5 mics, or was it mono mic'd and panned across the 5 channels, or something in between? This will greatly change how the bass summing will mix. Was the mix done on a system using bass managemant also? Was the room where the mix was done, and where it was played both Eq'd to the same curve and cross over point to the common sub-woofer?

All these questions and many more make it difficult to keep the results consistent across hundreds, or thousands of rooms of different sizes and shapes. Of course there are many people who like a bit of extra bass, so having the bass summing create the artificial boost makes it sound "better" than the creators original mix. We have even had some content creators admit that they liked an artifact like that, even though they knew it was not faithful to the original mix. My personal view is that I am in the business of RE-production, not PROduction. Once the content creator signs off on how it sounds on the dub stage, it is my job to make it sound IDENTICAL in the final theatre environment, not richer, crisper, boomier, etc. I have had some excellent results in smaller rooms using bass management when the owner chose to use some smaller main front speakers, but it took extra tuning time and some trade offs that made it sound a little different than the original intent.

When I do have to make a compromise on a system setup, the goal is to make any deviation from perfect playback be on the side of "pleasing to the ear". So in most cases we end up with a bit more bass in a bass managed system, but it is not as accurate to the original mix.

I love huge dynamic range when used well, but there have been some recordings that are just plain silly. I am sure you will know one I am speaking of. It is a 2 trk version of the 1812 Overture with real mic'd canons, but the producer made a choice where the canons are 40 db louder than the orchestra playing the music. To me this sounds like it was recorded to be the point of view of the man standing at the canon to fire it, while the orchestra was a half mile away. I was not the mixer or producer, I try to play it faithful to the creator's vision, but I just can't enjoy this version myself. I know that has little to do with the discussion, but you mentioning a recording of the 1812 Overture made me think of how much that recording bothered me. Just because we can make those canons that loud does not make it a good choice. There is a schene in a film called "Smokin Aces" where a girl fires a 50 cal. In one theatre, I felt it bounce the entire back wall of the auditorium over an inch from the pressure wave. Yet it was far more pleasing than those silly 1812 canon blasts. I screened that film at 4 different locations, and no two sounded alike. It was a very good use of the LFE track, but it also showed how difficult it is to match the lowest octave performance. This was not a case of low end responce, it was more about the attack speed of the pressure wave on the first cycle. Ported cabinets do not have any resonanse help on a shock like that. I never did get to hear it on an infinate baffle or Bag End sealed system, that would probably stop your heart for a second from the pressure pulse. As it was the bank of 18 18 inch woofers felt like getting punched in the chest, even at about 100 feet from the speakers. In a much smaller room, a bank of 6 18's with over 3000 watts behind it just didn't have near the thump on your ribs, even though my analyzer showed nearly identical 1/12th octave measured frequency response to well below 20 Hz. In fact, the thump seemed to have far more energy up at 80 to 100 Hz. In any case, this kind of a sound could never be produced from the main channels due to the 10 db gain difference below 125 hz. This is why I think the idea of 3 sub woofer feeds will work much better. Keep the screen speakers separate, use a dedicated high output LFE subwoofer, and then use smooth no in band gain bass managed sub woofers to augment the smaller surround speakers. The signal and demand placed on the two systems are quite different.

I also do understand that 60 cycle buzz will have higher harmonics, but you have to agree, even the 60 Hz sine wave can be located by human ears. True, it is not as easy to localize, but I know many people who can walk right to the source of a clean 60 Hz hum. I wanted to show an obvious example where bass summing would detract from a directors vision.

I am not saying to never use bass management, I agree it can be helpful, but I also feel it is over used and set up poorly far too often. I would rather have independant screen channels with a smooth roll off around 30 Hz rather than bass manage them below even 40 and go down to 20 Hz. Of course that is my personal preference. In the end, I will install what the customer wants and tune it as accurately as possible to re-create the original intent of the content producer. And in more than a few cases, the system owner then went in and cranked up the surrounds and low frequency levels to their taste. Oh Well, might as well pay for the ISF display calibration then crank up the blue to make the sky and water prettier too.
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post #80 of 1315 Old 04-26-2012, 12:48 AM
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Hi GXMnow,

Curious to know what your field of work is? Commercial audio system installer/calibrator? It's always fascinating to get insider viewpoints on the industry workings. In fact, in another thread, I had been musing about the whole bass management bit as I was mentioning how a fair number of BD movie soundtracks actually had more Low Frequency content in the Main channels than in the dedicated LFE .1 channel.


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post #81 of 1315 Old 04-26-2012, 01:13 AM
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Quote:
Originally Posted by GXMnow View Post

The tie to channel based systems had to be cut to go past 7.1 effectively. The 128 objects and 64 speaker feeds were chosen to keep the file size manageable and keep the system flexible.

I fully agree that the tie had to be cut but Atmos does it only halfway. There are still beds which is the old channel paradigm. Beds are pre-rendered content so to speak. I'm afraid they will be used a lot by content creators because it fits common production techniques.

The full potential of objects-based audio can only be released with a complete separation of audio data, spatial data (not only positional data but also virtual room data) and renderer.
Maybe it's only another 80 years or so from now until it will finally happen. Nevertheless, kudos to Dolby for moving in the right direction with a real product.

Markus

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post #82 of 1315 Old 04-26-2012, 02:01 AM
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Originally Posted by GXMnow View Post

I will just wanted to try to coment on some of Roger's last post about bass management here.I am sorry this got far longer than intended. I hope you read it as intended. This is not just about DOLBY ATMOS, as I feel it applies to any multi channel sound system.

I fully agree with everything Roger has said but would like to add some comments.

Bass management makes all those uncertainties in mixing and reproducing go away. The only drawback might be deliberate directionality at low frequencies in larger rooms like cinemas vs. unachieveable LF directionality in small rooms like living rooms and home theaters. In my mind a small price to pay.
By the way, using a 1/12 RTA for tuning bass frequencies might be the wrong tool to get really great results.

I know a studio that does remixing for DVD/Blu-ray without any bass management. There's a lot of LF content in the mains that never gets heard by the mixing engineer but will ultimately make it onto the disc. Not a desirable situation in my mind. The simple solution is bass management.

The described 60Hz hum problem is probably more relevant to an installer. But this should be easy to track down.
If there's hum in the mix then simply solo files/tracks. That's everyday business for a mixing engineer anyway.

Markus

"In science, contrary evidence causes one to question a theory. In religion, contrary evidence causes one to question the evidence." - Floyd Toole
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post #83 of 1315 Old 04-26-2012, 02:04 AM - Thread Starter
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Originally Posted by GXMnow View Post

I will just wanted to try to comment on some of Roger's last post about bass management here.

There are certainly many ways to implement speaker systems that cover the audible spectrum. I do not claim that bass management is the optimal solution. It's just very cost effective.

From what we have seen, the electrical summing issue does not appear to impair the result. Not even the mixing engineers who hear their own content at home have ever complained about it misrepresenting their mixes. Probably because bass is not mono'd and equally distributed across the channels. The IMAX test with 4 channels of identical, coherent bass is luckily not representative of what exists in 5.1 mixes.

The issue in my opinion is simply that content exists in those main channels that is not being heard by the mixers (let alone theatergoers). If it is not intended to be heard, it ought not be there because it wastes power and headroom.

When I was designing the bass management systems for Dolby Digital licensed products back in the '90s, I asked David Grey (the main man in the Burbank office) if, since mixers never heard it, we should require high-pass filters in the main channels to ensure consumers got the same experience. He advised against it. I think that was the right answer. It was unfortunate that the content creators were left in the dark by not having any means to know what was going on in that bottom octave.

And while electrical summing has its compounding effect, it is not very difficult for Dolby to devise an active bass summing processor to exactly compensate for that, thereby matching the bass energy of separate full range speakers regardless of the coherence. Might have been a nice feature for the Atmos processor. Who knows, maybe it's already in there.

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post #84 of 1315 Old 04-26-2012, 05:23 AM
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Necessary for what? My point wasn't about the number of speakers but the motive you assign for inventing newer technologies that can take advantage of more speakers. At best, you're projecting.

Projecting for what?
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post #85 of 1315 Old 04-26-2012, 05:45 AM
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Gary,

you make it look like Atmos was "invented" for the sole purpose of selling more speakers. This simply isn't true. Although I agree that it can be (mis)used to do so, dumping the old channel based systems for object based audio is of much greater importance. Just because the invention of the electric light bulb helped sell even more "candles", it obviously had a much larger impact.

Markus

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post #86 of 1315 Old 04-26-2012, 06:16 AM
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Gary,

you make it look like Atmos was "invented" for the sole purpose of selling more speakers.

Don't blame them even if true. As I said there is not much left to sell after surround, Room EQ and lossless. Neither did I say it is a bad thing. It is a niche thing. I don't see many HTs (let alone households) with 14 speakers any time soon. Yes the object based strategy sounds good but a what cost? It's not exactly just another chip on your AVRs processor board. It sounds good for commercial theaters though.
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post #87 of 1315 Old 04-26-2012, 07:38 AM
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Originally Posted by Gary J View Post

Don't blame them even if true. As I said there is not much left to sell after surround, Room EQ and lossless. Neither did I say it is a bad thing. It is a niche thing. I don't see many HTs (let alone households) with 14 speakers any time soon. Yes the object based strategy sounds good but a what cost? It's not exactly just another chip on your AVRs processor board. It sounds good for commercial theaters though.

The implications of moving from channel based reproduction to audio objects is more profound than moving from mono to xx.x surround. It's more of a revolution than an evolution, especially for home reproduction.
I don't believe the movie theater business model will gain much from object based audio (unless they can keep it exclusive to theaters) nor do I think it will survive in the long run. But it's a very good thing that it's still strong enough to drive innovation like object based audio.

Markus

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post #88 of 1315 Old 04-26-2012, 07:47 AM
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Originally Posted by djbluemax1 View Post

Hi GXMnow,

Curious to know what your field of work is? Commercial audio system installer/calibrator? It's always fascinating to get insider viewpoints on the industry workings.

I have met GXM.

I can assure anyone reading this that he most definitely has reliable information regarding Atmos.
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post #89 of 1315 Old 04-26-2012, 07:49 AM
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From what I see this thread has drawn the interest of pretty much just the high end 1 per centers. We shall see.
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post #90 of 1315 Old 04-26-2012, 07:52 AM
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Originally Posted by markus767 View Post

I don't believe the movie theater business model will gain much from object based audio (unless they can keep it exclusive to theaters) nor do I think it will survive in the long run.

Pardon my slightly OT follow-up, but you don't think movie theaters will survive?

Jeff
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