Three missing audio features in all of Todays Immersive audio AV processors/receivers

[EB1000]

Hi

I was wondering how home none of the 3D audio processors and receivers don't offer these useful audio features, one would expect from an immersive sound compatible processor:

1. Native support for Dolby Atmos from music streaming services like Tidal, Amazon HD, and Apple music. You do get support for these services on most immersive audio based receivers, but only in 2 channel audio (you could of course upmix it to 7.1.6 using DSU/ DTS Neural X, but it's not the same). To get Atmos music on AVR, you still need an Apple TV 4k connected via HDMI.

2. Support for Dolby Atmos Headphones. Why no AV receiver offers Atmos via its headphones jack like you get from any Windows 10 PC after buying/installing the Dolby Headphones app and drivers? This is a feature you'd expect from any AVR that carries the Dolby Atmos logo. I've tested both my Yamaha RX-A2070 and my Denon A4400H. When you play an Atmos content while using headphones, sound effects intended for the heights are heard from the left and right directions. An Atmos to Binaural/Spatial/3D audio for headphones would be a great thing to have for late night watching.

3. Binaural recordings to immersive surround upmixer for getting the maximum from binaural recording without headphones. There are many music recordings and albums, which were mastered for 3D headphones experience, such as Sony's 360 reality audio, Apple spatial audio, and other unbranded binaural recordings. Why not add a listening mode like DSU and Neural X, which decodes 2 channel binaural recordings into multichannel immersive surround? Such is possible by the already included powerful DSP.

The way I see it, such features would help get the maximum out of any home theater setup with 5.1.2 channels and up.

 

[stevenswall]

This makes me seriously reconsider getting at Atmos capable surround sound processor.

 

[dlaloum]

at a guess..... One word - Licencing.

Also it would be great if AVR's could also include proper HRTF processing and Headphone EQ... an extension of Dirac, Audyssey or others...

 

[pedrob]

Be that as it may, I wouldn't let it spoil your enjoyment. There are plenty of processing options that sound terrific. Just select the one that sounds best to you.

 

[Laniciffo]

Regarding 3d audio...

How many authentic multi channel audio recordings do you know?
I have looked for some but found very few, and those were compressed Dolby surround things from DVD audio discs, re-engineered long after the original issue of the album.
I fear there are even less 3d audio recordings as the 3d codecs are based on the concept of 'audio objects', which might be difficult to apply to pure audio.

One other important issue is that there apparently is no standard for recording multi channel audio. Mic positioning, levels, etc...
From which seat in the concert room should they record?
And what should they do for studio recordings?

And also think that the surround speakers are generally (much) smaller than the main ones. This is ok for creating 'cinema effects' that do not care too much about fidelity, but how could the sound engineers mastering the recording take into account the different tonal responses? Room EQ of multi channel systems can not fully compensate these differences.

I think I got all of those elements from a Harman group article that you could find with G*.
This should give you a much better response than my increasingly weak memory.

 

[Kal Rubinson]

How many authentic multi channel audio recordings do you know?

Thousands. Mostly classical.

And also think that the surround speakers are generally (much) smaller than the main ones.

Not necessarily but, "generally," a user choice. Besides, "generally" most speakers in general use are tiny and awful; that, too, is a user choice.

Room EQ of multi channel systems can not fully compensate these differences.

"Fully" is a tough standard but good DSP corrections and bass management can get pretty close, especially, if one considers the spatial variations in human audition.

One other important issue is that there apparently is no standard for recording multi channel audio. Mic positioning, levels, etc...
From which seat in the concert room should they record?
And what should they do for studio recordings?

Saved this for last since, just as with stereo, it is a matter for the artists and the recording engineers to do, well or poorly, and there's no agreement among live concert goers about which is the best seat in the house. Look up Toole's "Circle of Confusion" which encompasses all the variables.

 

[Vacceo]

Not necessarily but, "generally," a user choice. Besides, "generally" most speakers in general use are tiny and awful; that, too, is a user choice.

This comment allows me to ask a couple things. First is what would you call tiny and, conversely, adequate? Is it a matter of frequency response? Pure cabinet volume?

And second: active speakers can "cheat" in not being tiny. How much "cheating" is possible at a given cabinet volume?

 

[Plcamp]

The thing that bugs me most about AVR’s is the lack of 2 channel digital outputs (optical for example) independent of which digital input is selected.

TV’s do that, why not AVR’s?

 

[Kal Rubinson]

This comment allows me to ask a couple things. First is what would you call tiny and, conversely, adequate? Is it a matter of frequency response? Pure cabinet volume?

I use all floor-standers in my main system but my thought was "acoustically tiny" in not being able to produce a flat, full-spectrum output at 100dB even if the bass went down only to 50-60hz. Not cabinet volume but, of course, Hofmann's Iron Law still applies.

And second: active speakers can "cheat" in not being tiny. How much "cheating" is possible at a given cabinet volume?

IMHO, you can cheat all you want if the results justify it. I've enjoyed both the D&D 8c and the Kii Three in my system.

 

[Vacceo]

By "cheating", I mean pushing lower than a passive bookshelf of the same size. Because active speakers can indeed get those 100 db on the 50 to 60 Hz band. The question is, how much can you gain on the lower end with a good active bookshelf: down to 40 Hz at 100db? More?

So on the first question, the answer would be a speaker able to provide meaningful spl even at 20hz?

 

[Timcognito]

@Kal Rubinson have you listened to and do think Dolby Atmos is a worthwhile and sonically? valuable technology?
Edit: For Music

 

[Kal Rubinson]

By "cheating", I mean pushing lower than a passive bookshelf of the same size. Because active speakers can indeed get those 100 db on the 50 to 60 Hz band. The question is, how much can you gain on the lower end with a good active bookshelf: down to 40 Hz at 100db? More?

That's for the speaker designer to determine.

So on the first question, the answer would be a speaker able to provide meaningful spl even at 20hz?

Not really. Adding a sub to extend the LF is OK with me.

 

[Kal Rubinson]

@Kal Rubinson have you listened to and do think Dolby Atmos is a worthwhile and sonically? valuable technology?
Edit: For Music

At the moment, it is iffy but that seems to be where new production is going. There's some good stuff and lots of bad stuff, atm.

 

[Vacceo]

Not really. Adding a sub to extend the LF is OK with me.

So your preference for rears and sides would be around real 40hz measureable (not what is printed in the promotional materials).

 

[Laniciffo]

Well, I am not a specialist of any of those topics and I see that the answers are quick. I will not try to argue on the technical ground, I do not know enough.
I just tried to echo what I had read from a Harman specialist (who seem to be well regarded on this forum) and from what I remember, he apparently considered multi channel audio as something quite difficult to implement with fidelity.
There are so many more variables than with just 2 channels that pretending to achieve high fidelity seems difficult, and this site demonstrates everyday that Hi-fi is a real challenge, even just for mono playback.

That said, I do declare that I love feeling the music completely surrounding me. I do not have a truly hi-fi system, just a home cinema setup. As I actually do not spend so much time seated and fully concentrated on the music, what I enjoy the most is setting my 7-speaker setup to its 'all zones stereo' mode to get that great presence everywhere in my living room, even if I don't remain seated.
And I think that this also improves the WAF of my loud listening sessions.

All in all, I actually partially share this desire to experience 3d audio, and I did try (just a little) to learn how to do, but after reading this article I thought that this is probably out of my reach.

I will follow this thread with interest to see if more knowledgeable people could show me good sources of content and good practices.

Ps: a few more more remarks that I just thought of :
- can the technical setup be sufficiently optimized to be good for all recordings?
- are the new multi ch recordings more a musician or a technician thing?

 

[Kal Rubinson]

So your preference for rears and sides would be around real 40hz measureable (not what is printed in the promotional materials).

No, that would be my tolerance for rears and sides. My preference would be another octave deeper.

 

[dlaloum]

No, that would be my tolerance for rears and sides. My preference would be another octave deeper.

And an Octave being a doubling or halving of the frequency in Hz.... that would make it 20Hz... ie: what is traditionally known as a "Full Range" speaker

 

[dlaloum]

No, that would be my tolerance for rears and sides. My preference would be another octave deeper.

P.S. I eagerly await Dirac's "Unison" functionality - and the ability to truly use, fully, the lower end of full range speakers running the rears/surrounds.... - it won't make subs redundant (they will still be needed for subsonics...) - but if your bass load can be handled by 4 or 6 woofers, all of which go down to 20Hz - would you really need a subwoofer in most cases?
(of course that would then push amplifier requirements for those channels up... no more weedy 50 to 70 W being ample for surround channels!)

 

[Head_Unit]

And second: active speakers can "cheat" in not being tiny. How much "cheating" is possible at a given cabinet volume?

Not that much in my opinion. Oh you can get quite good sound out of small stuff these days with DSP limiting and meddling with harmonics and bass boost, however in the end there's no substitute for cone area and cabinet volume. Enough power can boost the low end but smaller drivers stroking longer will just distort more than larger ones (given similar quality of magnetics and suspension). Theoretically it's possible to compensate for those distortions I guess but I'm not aware the technology exists yet.

 

[Vacceo]

Not that much in my opinion. Oh you can get quite good sound out of small stuff these days with DSP limiting and meddling with harmonics and bass boost, however in the end there's no substitute for cone area and cabinet volume. Enough power can boost the low end but smaller drivers stroking longer will just distort more than larger ones (given similar quality of magnetics and suspension). Theoretically it's possible to compensate for those distortions I guess but I'm not aware the technology exists yet.

I guess that a dsp and direct amplification without the losses of a crossover can push the capacity of the cones to its limits, but there is still a limit.

I'm asking this because my LS50 Wireless II reach quite low and quite clean for a bookshelf, they get to 60 Hz quite well, but I guess they cannot be pushed much further.