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State of the art Home Theatre - how?

JeffS7444

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Yes I would like to set up a sufficient Atmos system that would at least accommodate 4-6 people in the sweet spot.
Audyssey as implemented by Marantz already averages measurements from 6 different listening positions.
 

Soundmixer

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Yes I would like to set up a sufficient Atmos system that would at least accommodate 4-6 people in the sweet spot. I think you would be getting into 32 channel range just for that

My HT seats 5 people comfortably, and I only have a 7.1.4 system. The bottom line is this.....it does not really matter how many speakers are deployed, there is only one sweet spot in any given room. That is the one seat where the output of ALL the speakers' signals arrived at the same time.
While you may create a wider space with fewer frequency variations (especially in the bass), you cannot create a wider sweet spot with more speakers.


For example AirPods Pro support Atmos with head tracking. What would be the downside of such an implementation?

It can only accommodate one person is the only downside I can see.
 

JeffS7444

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Audyssey does not create a wider sweet spot.
Only so much that software can do; why not start with speakers which have good polar response characteristics, with particular emphasis on center channel midrange performance, so dialog can be understood by everyone?
 

srrxr71

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Audyssey does not create a wider sweet spot.

Isn’t the aim of very high order ambisonics to create a sound field in which the sweetspot is large enough that at least you can move your head in all directions and keep a stable image?

It should sufficiently resolving to play a bumble bee around your head convincingly enough that you move your head to try to locate the bee and yet keep a stable image. Maybe that can happen around 32 channels.

if you exponentially increase the number of channels you may even have a space within which you can physically move and keep a stable image.

Something like 1024 channels would have that kind of spatial resolution where you could move around maybe a 6 foot diameter circle. All the signals arriving on time are all calculated in that space only. i’m just guessing at those dimensions. Someone with knowledge of ambisonics would have the actual values. They are all mathematically derived.

I guess the application would be VR without headphones. Since most of us can’t fathom having 1024 speakers we’re going to have to wear headsets. If you’re ultra rich then I suppose you can play VR without needing to wear a headset. You may as well also get a 360 degree projection system.

i’m just saying even Atmos can scale up to that level so judging what is state of the art at a given moment in time will likely have to do with the number of channels you have.

I suspect even 7.2.4 is good enough for most people but with better technology maybe 16 channel could involve LCR and sticking a few boxes around the room. The main assumption in an cinema situation is that you are facing forward so maybe there are ways to increase apparent spatial resolution with fewer channels with that assumption. I suppose that is how even the most basic Atmos setups can be so good. Maybe 7.2.4 is enough. SOTA it isn’t though. The sky is the limit there.
 

Soundmixer

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Maybe 7.2.4 is enough. SOTA it isn’t though. The sky is the limit there.

SOTA is not defined by how many channels or how much a system costs. It defines the QUALITY of the system, not the number of speakers. A sound system of very high quality can be had by a 7.1.4 system (there is no such thing as .2) just as easily as a 22.1.10 system.
 

srrxr71

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SOTA is not defined by how many channels or how much a system costs. It defines the QUALITY of the system, not the number of speakers. A sound system of very high quality can be had by a 7.1.4 system (there is no such thing as .2) just as easily as a 22.1.10 system.

Fair enough. So at the very least you need multi sub and probably cardioid fronts and dsp for it work in your room at anything approaching SOTA. All those ambisonics equations may assume an anechoic chamber. At least below the transition frequency we have to have systems which can properly correct for room modes. Above it probably doesn’t matter because you will “hear through it”.

Those issues have barely been solved in 2 channel stereo. I mean they have been (sort of) if you can spend $30k on genelec w371 or kii bxt system. They still revolve around the paradigm of “stereo bass”. Far from holistic bass.

Those solutions need to get much cheaper to be viable for multichannel. They also have to account for holistic bass and midbass. What do you do between where subs go omnidirectional and the transition frequency? The best we have is cardioid. What if we had multi sub and multi mid bass but with a way to keep localization accurate? Some research needs to be done on that.

Afaik Dirac bass control is the only one that handles proper multi sub. Without you needing to buy a mini DSP and tweak it for hours. How do you get that? $4k + $399 and there is no hdmi 2.1 yet. I wouldn’t buy anything until that is sorted out.

So yes there are multiple issues that need to be worked out and we haven’t even worked them out for stereo in a way that a consumer can just buy and calibrate. Once multi sub is sorted out and found in consumer grade receivers then we can move onto solving the mid bass issue. Then we could work on upgrades would come in terms of spatial resolution which involves more channels. So yes you are right there are other problems to solve before we start adding channels. We haven’t even gotten to that point yet. Or you could go for spatial resolution and live with mid bass issues because that costs too much in time and money to handle. You get a lot of options in terms of what you can optimize for.

Maybe you can argue these issues have been solved by the beolab90 for stereo. Now where’s the solution for multichannel? 8 x $45k and 8 beolab 90s? Since we have so many channels there would be other creative ways to tackle the problem of room modes. What a consumer grade avr can currently do is good enough but it’s not SOTA. Limited bandwidth speakers plus one or even 2 subs isn’t going to cut it. Maybe you need 4 subs 4 mid bass plus extra midbass units in the front to keep localization accurate then you can add all your extra channels.

A denon receiver may calibrate for 6 spots but it’s just going to do the best it can with what it’s got. If all your channels are full range down to 25hz or so then it has a lot to work with. Not at all practical. If your channels are low frequency limited then you need multiple subs and multiple mid bass. Maybe it can use the mid bass from the surround channels to holistically manage room modes in that 100hz-500hz region. Do we know if the current algorithms work that way? You would still need speakers with constant directivity above 500hz. They are not cheap. Maybe a bunch of 8331s as surrounds?

My suspicion is that it would need to move towards mult sub and multi mid bass fully calibrated to give you a large sweetspot for transition frequency and below and then beaming forming speakers with head tracking for everything above transition frequency. At least surround speakers which don’t mess up the carefully corrected bass and mid bass.

So you can get quality with mounting beolabs on the ceiling but really we need to come up with more practical ways to get use all these channels to interact with the room properly. We are just on the cusp of solving these room issues and we are far from getting it perfect. Maybe Trinnov is it and maybe Dirac 3 with bass control will bring it into a reasonable range. I think there is more to be worked on and below transition frequency is a separate problem that plagues even 2 channel systems currently. The solution there would involve multichannel ways of thinking. So stereo and multichannel will converge and then adding channels would be easy to get the desired spatial resolution.

For now I suppose SOTA would involve multiple full range speakers in various positions and the level of dsp that can leverage all of them to deliver an accurate room response. You can believe that whatever your consumer level denon is doing is at that level but I suspect it is far from that currently. There has to be a smarter way than putting full range speakers everywhere.

If you tell me current state of the art is a trinnov and just 7.4.4 with 11 mains of beolab 90 or 8351/w371 or kii + bxt and 4 good subs then I would agree. The cheapest form of it would be $170k. I guess there are some options there for those who can afford it. It’s certainly miles above what we had 10 years ago where $170k was some crazy insanely expensive stereo pair with no room correction and $10k cables.

Also I think just like apple spent $Millions and 6 years development to put out the HomePods to be a Nano beolab type speaker it will take a mega corp like Samsung/Harman or Apple to put some engineering budget into these solutions. Something like homemains plus home subs and home surrounds and they all figure out exactly where you have placed them and to self calibrate the whole system holistically. Right now it’s most niche level budgets being thrown at these problems. They’ve done exceptionally well considering Dutch and Dutch, kii, genelec etc. But their budgets are a joke in terms of tackling these problems. We need mega corp money to really get this field moving towards consumer level SOTA and even then it takes years to develop products. The fact that Apple Music has now Atmos mixes for music is very important first step to open up this market. But how the HomePod (even at $199) failed in favor of a $99 joke orb doesn’t give me much hope. People will spend $100 on a week and a half of weekday lunches but won’t spend it on getting a real HomePod over a joke orb.

Now once we get the foundation right those “joke orbs” could be very valuable. They could have 4 drivers pointed in 4 different directions. You hang 4 of them on ceiling. 2 of them high on your front wall. 2 high up on each of your side walls. 2 on the back wall. That’s 48 channels right there. Just for heights. Atmos being object oriented can use them to add spatial resolution once their position and orientation is determined. Quality LCR is always a must given 80% of the sound comes from the front where the screen is. But once a proper foundation is laid channels could be added very trivially. So the thinking needs to move towards that. However I completely agree. LCR must be quality. And whatever solution for below transition frequency is used must also be quality. Processing power is cheap and getting cheaper every day. Your phone of today is more powerful than 100 computers of 10 years ago. So the foundations have to be laid to take full advantage of that.
 
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Soundmixer

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Fair enough. So at the very least you need multi sub and probably cardioid fronts and dsp for it work in your room at anything approaching SOTA.

Multi-sub is most definitely helpful, but not cardiod fronts or DSP. Dolby has never demo'd Atmos using the latter, so I am pretty sure that is not necessary to be SOTA for Atmos.


At least below the transition frequency we have to have systems which can properly correct for room modes.

We already have Trinnov, Dirac Live, and Audyssey that can do all of that.


Those issues have barely been solved in 2 channel stereo. I mean they have been (sort of) if you can spend $30k on genelec w371 or kii bxt system. They still revolve around the paradigm of “stereo bass”. Far from holistic bass.

"Stereo" bass does not really exist. Listening tests have already proven this. I have no idea what holistic bass is.

"
What do you do between where subs go omnidirectional and the transition frequency?

It is called bass management. You never run a sub all the way up to the transition frequency. You use a crossover point from the sub to the mains low enough that you never get to the transition frequency.


Afaik Dirac bass control is the only one that handles proper multi sub. Without you needing to buy a mini DSP and tweak it for hours. How do you get that? $4k + $399 and there is no hdmi 2.1 yet. I wouldn’t buy anything until that is sorted out.

You don't need HDMI 2.1 for movies or music, and you can buy a Monolith processor for 4K, and you don't need to spend any more than that to get Dirac Live with Bass control.


Maybe you can argue these issues have been solved by the beolab90 for stereo. Now where’s the solution for multichannel? 8 x $45k and 8 beolab 90s?

Multichannel is a solution in and of itself. Auro3D and DSU do a fairly good job of upmixing 2 channels - the former much better than the latter IMO.

"
Since we have so many channels there would be other creative ways to tackle the problem of room modes. What a consumer grade avr can currently do is good enough but it’s not SOTA. Limited bandwidth speakers plus one or even 2 subs isn’t going to cut it. Maybe you need 4 subs 4 mid bass plus extra midbass units in the front to keep localization accurate then you can add all your extra channels.

YOu are making this so complicated it is not funny. 4 subs in an SFM setup deals very well with room nodes and modes. You don't need mid bass units, you already have them in the main speakers. Based on what you state here, SOTA is a matter of perceived subjective opinion, not actual performance. Limited bandwidth speakers (80-20khz) coupled with high-performing subs (and quality amplification and processing), can certainly be considered SOTA.


If you tell me current state of the art is a trinnov and just 7.4.4 with 11 mains of beolab 90 or 8351/w371 or kii + bxt and 4 good subs then I would agree.

This tells me that your idea of SOTA is based on price and price only. SOTA can come in a package far less expensive (I do agree about the Trinnov, but you can throw Storm audio in there as well) than what you state.

You have an unnecessarily complicated view of what SOTA is when it comes to sound. I don't think we need all that you have stated in this post to achieve SOTA....especially when it comes to sound.
 

srrxr71

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Well I’ll put it this way. For video SOTA is trivial. LG OLED if up to 88” is okay for you otherwise you get:

https://electronics.sony.com/tv-video/projectors/all-projectors/p/vplgtz380

Plus the screen you like or the Sony engineer recommended.

Literally no arguments from anyone. Maybe a few alternatives.

After all it’s just light on a 2D. 4K is sufficient resolution some will argue 8k fine let them argue. Then contrast ratio. Which fundamentally is limited by your light control which can go up to the level of fitting black velvet on all your walls and black carpet. There you have it. SOTA? Done deal.

With audio it’s like a religion. It’s all about beliefs. Audyssey is SOTA. If you bought an audyessy xt product (still being sold) and took it home and let it calibrate and BELIEVED that it was “so much better” because oh marketing maybe. Then you became a believer.

Now read this:

https://audiosciencereview.com/foru...sey-multeq-vs-multeq-xt-vs-multeq-xt32.14786/

Let’s just be thankful everyone was kind enough to refrain from calling multeq xt “hot garbage”. Because fundamentally that’s what it was. I bet back then you thought it was all figured out. This product came from “smart engineers” who “knew what they were doing”

For more than 2 decades Yamaha has been advertising how they go to places like the Sydney Opera House etc. and make your 2 channel at home sound like it’s playing there. That’s a bucket of laughs. I’m sure people believed it. They bought that stuff after all.


Here you can see that Multeq xt32 finally applies modern (like all the harman stuff from around 2008 or so) acoustic knowledge to the problem correctly:

https://audiosciencereview.com/forum/index.php?threads/audyssey-room-eq-review.12746/


Amir is right when he says the kind of stuff they have to put in there is too cheap to store even 2 target curves. Then if you keep reading you will learn it will apply phase/delay independently to each sub but peq is the same for both. Seems half baked to me. Dirac maybe fixes all this? We won’t know for years until someone actually figures out what the black box is doing. Case in point? Multeq XT.

So now you think about this. A mini dsp runs circles around this thing. A $50 raspberry pi runs circles around a mini dsp. An iPhone runs circles around a raspberry pi. A 32 core amd cpu runs circles around an iPhone.

So you can choose to believe what you have is close to the SOTA. There are little mini cults too. The Bose 901 people (they like that sound and I can’t judge or blame them), the SET people, the horn speaker people, the cardioid people, the point source people, the line array people, the electrostat folks, the magnepan folks. The auro3D folks. Probably sounds good but how do you take create 8 channels from what was recorded in one plane from 2 microphones? There is spatial data contained in the phase differential between the 2 channels and so many ways to skin the up mixing cat. You like it. Many like it and that’s great. But it’s a preference that’s all. Maybe I would like it. I would like multi order ambisonic captures better as that can be traced back to a standard. Anything SOTA needs at least that. What were the mic planes and in which directions


You can’t have SOTA with so many opinions and beliefs.

Now you say Dolby doesn’t use dsp in their demo. Apart from the fact that entire Atmos format is based on dsp you mean they don’t use dsp room correction.

Right and they don’t need to. You can create a large enough room that the transition frequency is lower than 80Hz. You put an architect, plus acoustic engineer together and enough real estate why bother with dsp room correction?

In a real SOTA multichannel system the room is the most valuable part of the system. The equipment just needs to put out the required SPL once the room is built and treated and monitors soffited etc.

The entire point of DSP room correction is to bend the laws of physics enough get that performance in a domestic environment. Which is not a trivial thing to do. This is why Dolby doesn’t need DSP but you do.

Audio is a 3 dimensional thing. Creating a SOTA cinema sounding experience in your domestic environment is not easy. It’s just that people can be so overjoyed by all the whizz bang sound effects to not care that the tonality is off.

In fact you are right. It’s just sound who cares? It’s what? A music track + a dialogue track and a bunch of whizz bang effects for entertainment.

The question here is about SOTA so that’s why we care.

Now to even try to answer that we must at least be knowledgeable about what’s going on in the 3D audio world.

Just like computational photography is revolutionizing the photography world and really bending old rules about light hitting the sensor the same is happening in 3D audio.

If one can get over how what they own is 95% SOTA (I’ve personally bought a lot of junk over the years with that line of thinking) then one can open their eyes to what’s out there.

The Japanese want 22.2 for their next broadcast standard. Why? Are they stupid? The standards are flying out there. MPEG.H. 6th order ambisonics.

You may refuse to believe it but we are just now seeing the tip of the iceberg in terms of computational audio. Being happy with what you own is a good thing. But having been doing this for a while it doesn’t surprise me anymore to learn that what I used to think was the best thing since sliced bread is now objectively considered crap. Things change, progress happens, stuff gets discovered.

From your perspective we already have it. Just take Trinnov 32 and make it cheaper. Fire all the other engineers involved in 3D audio. Just make them all work on Trinnov 32 for the masses.

If you mean SOTA for today then in terms of dsp room correction it would be hard to argue against the Trinnov 32. But if you SOTA in terms of cinema experience in a domestic environment there is a lot of work being done on so many facets of the problem. A few google searches will help you realize that.
 

Soundmixer

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Now you say Dolby doesn’t use dsp in their demo. Apart from the fact that entire Atmos format is based on dsp you mean they don’t use dsp room correction.

What I mean is they don't use specialty speakers in their demos. They use great performing speakers, but not overly expensive ones.


Amir is right when he says the kind of stuff they have to put in there is too cheap to store even 2 target curves. Then if you keep reading you will learn it will apply phase/delay independently to each sub but peq is the same for both. Seems half baked to me. Dirac maybe fixes all this? We won’t know for years until someone actually figures out what the black box is doing. Case in point? Multeq XT.

Amir also said this.

"I came into this review expecting Audyssey to not perform. That was my experience and that of formal blind testing of it years back. The out of box results of this "XT32" version was better than I remembered. Still, using the App is mandatory to properly incorporate a target curve with more bass and removal of "BBC dip." Once there, I had no issues with its performance and I think it comes very close to advanced solutions like Dirac and Anthem ARC. "

Seems like your issue with the EQ is a non-issue to him. MultiXT is no more, so no need to mention it.


Right and they don’t need to. You can create a large enough room that the transition frequency is lower than 80Hz. You put an architect, plus acoustic engineer together and enough real estate why bother with dsp room correction?

You bother with it because no matter what room you put a speaker in, or how well the room is built, it will need correction. There is no perfect room.

In a real SOTA multichannel system the room is the most valuable part of the system. The equipment just needs to put out the required SPL once the room is built and treated and monitors soffited etc.

I agree about the room, that goes for two-channel as well. Once again, it is not all about sound QUANTITY, it is about sound QUALITY....or both!

The entire point of DSP room correction is to bend the laws of physics enough get that performance in a domestic environment. Which is not a trivial thing to do. This is why Dolby doesn’t need DSP but you do.

EVERYONE (including Dolby) needs room correction.


Audio is a 3 dimensional thing. Creating a SOTA cinema sounding experience in your domestic environment is not easy. It’s just that people can be so overjoyed by all the whizz bang sound effects to not care that the tonality is off.

It is easier than you think! The second point is an assumption that you cannot quantify. There is more to a movie than whizz-bang sound effects, there is something called a film score. As a soundmixer, I like to hear the entire package when it comes to the soundtrack, not just the effects. Hugo didn't have a single explosion in it, and its soundtrack is beautiful to listen to.

"In fact you are right. It’s just sound who cares? It’s what? A music track + a dialogue track and a bunch of whizz bang effects for entertainment."

Since I mix those soundtracks, I care.


"Now to even try to answer that we must at least be knowledgeable about what’s going on in the 3D audio world."

I would dare to say I am pretty knowledgeable since I work in the 3D audio world.

Just like computational photography is revolutionizing the photography world and really bending old rules about light hitting the sensor the same is happening in 3D audio.

Agreed!

If one can get over how what they own is 95% SOTA (I’ve personally bought a lot of junk over the years with that line of thinking) then one can open their eyes to what’s out there.

This is an assumption that everyone thinks in one monolithic way, and people don't. I have one HT that most folks would consider 95% SOTA, and I can see there is a lot of great equipment out there. The thing is, I am not chasing perfection through equipment.

The Japanese want 22.2 for their next broadcast standard. Why? Are they stupid? The standards are flying out there. MPEG.H. 6th order ambisonics.

The Japanese WANT 22.2, but implementing it hasn't been done. 22.2 is not practical for most homes, so yes, I do think it is stupid. You can't even get people to adopt 7.1.4 or 5.1.4, how are you going to get them to adopt an expanded version of the Auro3D speaker setup?


You may refuse to believe it but we are just now seeing the tip of the iceberg in terms of computational audio. Being happy with what you own is a good thing. But having been doing this for a while it doesn’t surprise me anymore to learn that what I used to think was the best thing since sliced bread is now objectively considered crap. Things change, progress happens, stuff gets discovered.


You make a lot of assumptions, and I am not sure why. Anyone who has been into audio knows advancements in technology can render what was SOTA yesterday obsolete today. Your statement here is a "duh" statement to be sure.


From your perspective we already have it. Just take Trinnov 32 and make it cheaper. Fire all the other engineers involved in 3D audio. Just make them all work on Trinnov 32 for the masses.

Another assumption, I never said any of this! It is not cool to assume stuff that you don't know just to fill in the gaps of that lack of knowledge.


If you mean SOTA for today then in terms of dsp room correction it would be hard to argue against the Trinnov 32. But if you SOTA in terms of cinema experience in a domestic environment there is a lot of work being done on so many facets of the problem. A few google searches will help you realize that.

Honestly and respectfully, This is just plain stuff and nonsense. Why don't you provide some of those google search results to bolster this "interesting" comment.
 

srrxr71

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Certainly you don't have to go overboard on speaker cost. I agree. I like point source so my idea of "SOTA" is at least some form of a Genelec one. Others want D&D 8C.


If you refer to this calculator which shows an inherent huge advantage in Dolby sized rooms.

https://www.acoustic.ua/forms/room-modes-eng.html


They take mid bass issues right out of the equation keeping the schoeder frequency below the subwoofer crossover point of usually 80Hz let's argue. On top of that foundationally sound size, they also feature expert acoustic design. Then DSP is the sweet icing on the cake - computational power is cheap. Domestic rooms on the other hand have issues all the way up to 300Hz. So the starting point for what DSP has to work with is worse and would require even more power and a different thinking paradigm to attack.
If you consider something like a HomePod with an A7 chip driving 9 channels and 7 mic channels each plus all that other stuff it does. IMHO there needs to be an easy way to calibrate for a selectable size bubble around where your command voice came from. This is theoretically possible in something set up like a HomePod with its 7 mics or so. This came out 5 years ago. Even the best current AVR correction has you fiddling with a single mic and moving it around and testing and retesting. I still think the listening position mic is needed as an adjunct and also for verification. Maybe scientifically having multiple mics collocated with the speakers obviates this need depending on their number and positions. Am 11 channel system could have 44 or 66 mic channels. We certainly have seen that level of processing in a $199 HomePod. If you had 11 HomePods you’d have 77 mic channels and 99 independent output channels in the system.

I really would like to see that level of decoding and room correcting power on the fly applied to this SOTA home cinema 3D audio in a domestic room problem. One could choose to wait for that era or one could, in the meantime, dabble via MSO (multisub optimizer - please google if you wish, also there is a wonderful 2 hour video showing the results he gets and they are incredible) or get Dirac bass control until that era kicks off. Still doesn’t address the midbass problem in domestic sized rooms. That would require a paradigm shift in thinking with multiple midbass units also Monte Carlo optimization for the room and listening window. I would argue for me SOTA would need to consider that problem to start which we haven’t even begun. Right now even the under 80Hz correction issue has no consensus. Maybe in 2 years with easier availability of Dirac bass control we might finally put the under 80hz issue to rest. Then we can work on 80-300Hz.

I think Samsung/Harman should also have something in that space. Applying some real computational power to the problem. Samsung makes very powerful ARM CPUs. So for example the speakers, wherever you put them, would self calibrate and the system would know the position of each channel and set delay, phase etc automatically. Bass at the listening window automatically calculated with serious Monte Carlo simulation level like MSO. Midbass similarly dealt with. One key advantage to this is that it could perfectly translate an Auro3D signal to an Atmos layout or any layout for that matter. The system would be layout agnostic within reason. Domestic room issues are real. You have items which conflict with ideal positioning. Ceiling fans, lighting, artwork, furniture, windows etc.

So I have my requirements for SOTA. This is debatable and hence sheds some light on the OP's question on why we don't agree on SOTA. Its just debatable. As usual in audio - too many factions.


On Amir's statement it is also clear that multeq xt32 does not meet "SOTA" level so we must rule it out. It’s pretty decent which is not SOTA.

I am always open to and excited to get into multichannel and stereo upmixing. So let's consider HTP-1.

It is out of stock and I hope they are updating to HDMI 2.1 - just personal preference in terms of waiting on that before dropping $4k + software cost.

I will buy a copy of 4K Hugo and check it out.

I would consider Japan engineers want 22.2 for some logical reason. So should we want that number of channels potential in something defined as "SOTA"? Arguably yes and I hope they get it. More content would be created in consideration of 22.2 which can always be down mixed via DSP.

Trinnov is truly special and for some their definition of "SOTA" would require it. PC platform is honestly great. Imagine what they can do with that power. But it does need to come down to ARM silicon for this to take off. Much lower cost that way. I want these guys to keep pushing. Making better cheaper products over time. But also pushing the envelope generally requires the flexibility of the PC platform. They can push SOTA on PC but also let the principles trickle down to cheaper ARM hardware.

The term SOTA includes the word "art". Art requires a level of OCD. If we didn't care we wouldn't be here. So mine manifests in having to run MSO (multi sub optimizer) on any setup (outside the sold out and expensive HTP-1) and that is a manual process. That needs to be automated to aid in adoption. So Dirac Bass control over time will hopefully get more adoption and more development funds and get into cheaper products in just 1-2 years.

What is your idea of SOTA? And I understand this is personal preference and why there is no consensus on this.
 
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srrxr71

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Like a lot of people on this site, I am amazed that there is no really State Of The Art home theatre solution.
Even $17,000 AV processors perform far worse than a $100 DAC.
I would love to have some input on how could we do a SOTA HT.
For a stereo system it's not too hard - with AES outputs we can do all the equalisation and crossover before the DAC.
Plenty of nice DACs with >120 dB performance.
Active speakers and we're done.

For home theatre with active speakers we end up with a lot of channels if we have 7.1 or more system x 2 or 3 way.
But a harder problem is the source material, we seem more or less stuck with an AVR for all the licenses for the latest Dolby and DTS lossless CODECs.
And the onboard DAC implementation in even the most expensive is not SOTA.
And the license rules mean no accessible PCM streams we can send to be equalised, crossed-over and then DACed in a SOTA DAC.

So far the best approach seems to be to use the excellent @Weeb Labs videos to hack an AVR to extract the I2S streams, possibly convert to AES.
Once we have I2S or AES then what?
We need volume control, usually done in the AVR after the DAC AFAIK.
So a multichannel DAC with volume control, maybe the Okto 8 once it becomes re-available.
But for multi-way active speakers, can multiple units be tied to work in unison?
What about the DSP and crossover?
Does this sound like a project anyone else would be interested in?

David

Sort of embarrassing to admit I’ve been writing in this thread and just now really read your original post.

In terms of a theoretical discussion about SOTA i would be inclined to argue the Trinnov would fit that bill. So yes you would have to hack the I2S out of it and then directly convert to AES and use something like Genelec GLM for whole system volume control. That way you keep everything digital up to the last point. You would use the DSP of the Trinnov but GLM only for volume. I’m not too familiar with the other digital monitor systems and whether they offer full system digital volume control. So this is an option.

If you feel digital volume control has no place in a SOTA system then this problem gets complicated. However I would argue this is an opinion matter. Especially when the signal is output at a 24bit depth.

SINAD to compare DACs is important to see what kind of engineering went into them and compare them. However if you think of a room with even 55dB ambient noise and let’s say a horrible SINAD of 80dB you still have output to 135db before the system’s poor SINAD becomes audible in that room. Now it would be hard to call the system SOTA with such poor SINAD but the audibility of it is debatable. Perhaps it makes up for it in terms of being exceptional in something much more audible.

Personally I would take the SINAD hit to avail of the DSP in the Trinnov. This is borderline blasphemy in audiophile circles I suppose but I think in real world use the DSP is more important. But it clearly is an imperfect situation. Why not have higher quality D/A conversion in such an expensive unit? Would it add $1-2k to its cost? About 6% extra? People in that market would pay it for piece of mind. Clearly people are hacking these to get it and thinking of solutions that would cost more than $1k to fix this. Add the value of your time to the equation and this is an expensive fix for what arguably should have been dealt with by the designers.

There are people who feel modern a/d and d/a conversion is transparent. Many of them make the music you listen to. Who knows what their chain involves and what SINAD the A/D and D/A converters they used. I wouldn’t be surprised to see multiple unnecessary conversions in there. I hope not. I like to think apart from initial A/D conversion everything is kept purely 24/192 to the end of production. I somehow doubt this is the case.

Personally I feel SOTA sound in a domestic room has a lot of issues which need to be tackled and too many with higher actual audibility. It’s easier for me to just rule out DAC SINAD (likely you would not agree) as one of those issues and just settle for what’s commercially feasible. Because audibility is questionable.

SOTA requires a level of OCD and maybe we disagree on which aspect it should be applied to. You may believe it should be focused on the DAC SINAD. I think it should be focused on using advanced DSP techniques to create a flat response (you can add your curve later) at the listening position. In a domestic room this is a huge challenge which we haven’t really gotten creative enough about.

You can have your system certified to SINAD 120dB but room modes under 300Hz plague the output. So we both feel commercial implementations are flawed for different reasons primarily yet all reasons are still valid and likely agreed upon but with different priority levels.

I suppose the DRM restrictions in play prevent a 2 box solution to improve SINAD so that is going to be out of the question. So it would involve some box within a box construction and adds let’s say $2k to the retail cost of the solution. If you want SOTA in that aspect you have to pony up for it. But the market for that kind of chassis design probably isn’t there. An AVR has to be built cheaply to sell. Most of them cost less than $2k. I would prefer that money to be spent on better DSP software research and design and I think that’s what Trinnov did. Basically a philosophical difference which not everyone would agree with. The market seems to be dictating that money be spent on the DSP software/hardware instead of chassis design to get higher SINAD.


This is why given commercial feasibility plus DRM restrictions and current correction and measurement paradigms we are far from SOTA even in the aspects we are aware of. There are aspects we may not discover until another round of listening tests get done. This is like saying there known problems which we work on and implementing solutions for at a commercially feasible cost. Known unknowns where we recognize a gap in our knowledge and we work towards filling them until they are known enough to develop solutions for. Finally unknown unknowns which we will learn about as we keep doing listening tests and psychoacoustic research.

I guess SOTA in this 3D audio in domestic space problem will always involve some compromise somewhere even if we simply deal with known problems at this point. Consider Schroeder frequency. We’ve known about that since the mid 1940s. 80 years later we still don’t have a definitive consensus solution for under 80hz, which thankfully, we are close to solving.

Now how many years to solve 80-300Hz? Thankfully modern DSP tech evolves at an exponential rate. So it won’t be 80 more years but maybe 5 hopefully. Commercial feasibility is a huge issue and that’s why I think the stage is set for multi million $ companies to pay for this kind of development pace. Companies I respect like Trinnov, Dutch and Dutch and even Genelec can’t even dream of creating the tech found in a $199 HomePod. While, in and of itself it is not satisfactory for a high end system, that concept scaled up is where we need to go. We are just getting started IMHO.
 
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GXAlan

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That only affects the >1kHz range, not the 150-500Hz range which is still very rocky.


Might be due to that but, still, there is no reason why there's no impact on those wild FR swings.

It might be the difference between Audyssey XT versus Audyssey XT32.
 

FrantzM

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Sort of embarrassing to admit I’ve been writing in this thread and just now really read your original post.

In terms of a theoretical discussion about SOTA i would be inclined to argue the Trinnov would fit that bill. So yes you would have to hack the I2S out of it and then directly convert to AES and use something like Genelec GLM for whole system volume control. That way you keep everything digital up to the last point. You would use the DSP of the Trinnov but GLM only for volume. I’m not too familiar with the other digital monitor systems and whether they offer full system digital volume control. So this is an option.

If you feel digital volume control has no place in a SOTA system then this problem gets complicated. However I would argue this is an opinion matter. Especially when the signal is output at a 24bit depth.

SINAD to compare DACs is important to see what kind of engineering went into them and compare them. However if you think of a room with even 55dB ambient noise and let’s say a horrible SINAD of 80dB you still have output to 135db before the system’s poor SINAD becomes audible in that room. Now it would be hard to call the system SOTA with such poor SINAD but the audibility of it is debatable. Perhaps it makes up for it in terms of being exceptional in something much more audible.

Personally I would take the SINAD hit to avail of the DSP in the Trinnov. This is borderline blasphemy in audiophile circles I suppose but I think in real world use the DSP is more important. But it clearly is an imperfect situation. Why not have higher quality D/A conversion in such an expensive unit? Would it add $1-2k to its cost? About 6% extra? People in that market would pay it for piece of mind. Clearly people are hacking these to get it and thinking of solutions that would cost more than $1k to fix this. Add the value of your time to the equation and this is an expensive fix for what arguably should have been dealt with by the designers.

There are people who feel modern a/d and d/a conversion is transparent. Many of them make the music you listen to. Who knows what their chain involves and what SINAD the A/D and D/A converters they used. I wouldn’t be surprised to see multiple unnecessary conversions in there. I hope not. I like to think apart from initial A/D conversion everything is kept purely 24/192 to the end of production. I somehow doubt this is the case.

Personally I feel SOTA sound in a domestic room has a lot of issues which need to be tackled and too many with higher actual audibility. It’s easier for me to just rule out DAC SINAD (likely you would not agree) as one of those issues and just settle for what’s commercially feasible. Because audibility is questionable.

SOTA requires a level of OCD and maybe we disagree on which aspect it should be applied to. You may believe it should be focused on the DAC SINAD. I think it should be focused on using advanced DSP techniques to create a flat response (you can add your curve later) at the listening position. In a domestic room this is a huge challenge which we haven’t really gotten creative enough about.

You can have your system certified to SINAD 120dB but room modes under 300Hz plague the output. So we both feel commercial implementations are flawed for different reasons primarily yet all reasons are still valid and likely agreed upon but with different priority levels.

I suppose the DRM restrictions in play prevent a 2 box solution to improve SINAD so that is going to be out of the question. So it would involve some box within a box construction and adds let’s say $2k to the retail cost of the solution. If you want SOTA in that aspect you have to pony up for it. But the market for that kind of chassis design probably isn’t there. An AVR has to be built cheaply to sell. Most of them cost less than $2k. I would prefer that money to be spent on better DSP software research and design and I think that’s what Trinnov did. Basically a philosophical difference which not everyone would agree with. The market seems to be dictating that money be spent on the DSP software/hardware instead of chassis design to get higher SINAD.


This is why given commercial feasibility plus DRM restrictions and current correction and measurement paradigms we are far from SOTA even in the aspects we are aware of. There are aspects we may not discover until another round of listening tests get done. This is like saying there known problems which we work on and implementing solutions for at a commercially feasible cost. Known unknowns where we recognize a gap in our knowledge and we work towards filling them until they are known enough to develop solutions for. Finally unknown unknowns which we will learn about as we keep doing listening tests and psychoacoustic research.

I guess SOTA in this 3D audio in domestic space problem will always involve some compromise somewhere even if we simply deal with known problems at this point. Consider Schroeder frequency. We’ve known about that since the mid 1940s. 80 years later we still don’t have a definitive consensus solution for under 80hz, which thankfully, we are close to solving.

Now how many years to solve 80-300Hz? Thankfully modern DSP tech evolves at an exponential rate. So it won’t be 80 more years but maybe 5 hopefully. Commercial feasibility is a huge issue and that’s why I think the stage is set for multi million $ companies to pay for this kind of development pace. Companies I respect like Trinnov, Dutch and Dutch and even Genelec can’t even dream of creating the tech found in a $199 HomePod. While, in and of itself it is not satisfactory for a high end system, that concept scaled up is where we need to go. We are just getting started IMHO.
I’ll reply to this post in more detail later.
One thing caught my eye:
Companies I respect like Trinnov, Dutch and Dutch and even Genelec can’t even dream of creating the tech found in a $199 HomePod.
That is not true. Innovation is not limited to those mega companies. It could actually be said that smaller companies could be more nimble and focused. That is one reason why these behemoths , regularly acquire smallish companies whose innovations their billions could not come up with. Apple had to gobble Promephonic to make Apple Music compete with Spotify, for example. In spite of all its billions, Apple is not the leader in streaming space. Spotify and Netflix are. So …
Later …
 

srrxr71

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I’ll reply to this post in more detail later.
One thing caught my eye:

That is not true. Innovation is not limited to those mega companies. It could actually be said that smaller companies tend to ne more nimble and focused. That is one reason why these behemoths , regularly acquire smallish companies whose innovations their billions could jot come up with. Apple had to gobble Promephonic to make Apple Music compete with Spotify, for example. In spite of all its billions, Apple is not the leader in streaming space. Spotify and Netflix are. So …
Later …

Definitely agree. No doubt about it.
It’s just bringing it to mass market requires the big boys. Especially doing product design and making it hit a BOM point.

If you ask me the guy who created MSO is miles ahead of these corps.

It is rare that an corp does original research for a product but Apple did for the HomePod. That was a complete rethinking of a speaker. That kind of thinking could roll out into higher performance products. That level of rethink required $millions. They even built an anechoic chamber for it. I suppose today a klippel would allow for smaller more nimble firm to compete.

I can only hope Samsung/Harman is working on a modern completely rethought out system also.

I came onto Apple Music only because they bought MOG btw. I was upset, I still think MOG was a better product and all my playlists - gone.
 

srrxr71

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Honestly, you could have saved the 10,000-word comments and said this, and I would agree totally.
Could have but wanted to point out there’s a lot going on out there.

I didn’t even mention the work being done on stuff like dialog intelligibility, and allowing users choices in terms of what parts of a soundtrack they want or emphasized or deemphasized etc.


Speaker positioning agnostic systems. Beam forming. The equivalent of foveated rendering for 3D audio. Which could lower complexity based on hearing tests. Head tracking. Stuff I haven’t even heard of yet. Atmos laid a good foundation I would admit. Money spent on good LCRs is never a waste. Everything else is in flux.

It gives people a lot to look forward to with the unfortunate side effect that people may prefer to wait and see rather than buy buy buy now now now.

Just reading the Wikipedia entry on ambisonics and all the sub articles at the bottom is a rabbit hole of audio history and future promise. Also interesting facts like how Dolby bought and liquidated Barcelona based ambisonics company imm sound before launching ATMOS.

Finally someone implemented these ideas we had in the 1970s into a commercially viable format - in 2014. Some of these things take time to bake.
 
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