How does one create phantom speakers?

[2Sunny]

I have a Sony STR AZ7000ES AVR and the 360 Spatial Sound Mapping is impressive, but I'm scratching my head trying to understand what the technology actually does to create phantom speakers or put another way to make my ears think there is a sound coming from someplace where there is no speaker. Is it all about timing or phase or is it much more complicated?

 

[Oddball]

It's actually simple. Nothing exists that would work that way.

Closest would be to built an actual room and engage very expensive consultants to build in all the room treatments for the intended system.

 

[staticV3]

I have a Sony STR AZ7000ES AVR and the 360 Spatial Sound Mapping is impressive, but I'm scratching my head trying to understand what the technology actually does to create phantom speakers or put another way to make my ears think there is a sound coming from someplace where there is no speaker. Is it all about timing or phase or is it much more complicated?

In the simplest form, playing the same audio at equal loudness on two speakers will sound like it's coming from the center point between the two speakers. See phantom center.
Play with balance and phase and you can virtually sweep the full line between the two speakers.

If you want to project the sound from a place that's not a midpoint between two speakers, then you could bounce the sound off a wall or ceiling.

And if neither is an option, then you'd have to play with HRTF processing - essentially baking in the sound profile that you would hear if the sound came from where you want it to come.

this becomes very complicated with loudspeaker systems.

 

[NTK]

If one wants to fully geek out on the technology, the Sony 360 Reality Audio is based on Fraunhofer's MPEG-H.

360 Reality Audio Immersive Music Services and Devices Announced with MPEG-H – Fraunhofer Audio Blog

www.audioblog.iis.fraunhofer.com

You can learn all about MPEG-H here:

MPEG-H Audio

MPEG-H Audio is the new, next-generation audio technology providing more realism through sound from above as well as around the listener. With its unique personalization features, MPEG-H Audio offers viewers great flexibility to actively engage with the content and adapt it to their own preferences.

www.iis.fraunhofer.de

 

[2Sunny]

It's actually simple. Nothing exists that would work that way.

Closest would be to built an actual room and engage very expensive consultants to build in all the room treatments for the intended system.

Not to be taken personally in any way shape or form, but I'm afraid my personal experience does not corroborate that statement

On my system if I play the scene from Harry Potter Chamber of Secrets where the professor releases Cornish pixies into the classroom there is a noticeable difference with Sony's 360 Spatial Sound Mapping ON and OFF. I wasn't sure if it was my bias at work so I had my son turn 360 SSM off and on at random times with several different scenes and I was able to pick out SSM being on about 4 out of 5 times correctly. With SSM ON the Cornish pixies sound as if they are in the middle of the room where as with it OFF they sound behind or in front or above but definitely not in the middle of the room. So it seems clear to me that Sony's 360 SSM is in fact creating "phantom" speakers as they claim in their marketing. From what staticV3 indicated I'm guessing there is a fairly complicated processing involved.

The primary reason I am asking this question is because I plan on using REW + a Marantz Cinema 30 + Audyssey MultiEQ to try and create a room correction EQ for my home theater, but now I'm thinking that no matter how good of a room correction one creates it won't match the effect of Sony's 360 SSM technology.

However, as I have said before in other recent posts I have been very wrong of late so it would come as no surprise if I am wrong about this as well and that 360 SSM really is just Snake Oil and good room correction will create an equally good sound.

 

[LTig]

In the simplest form, playing the same audio at equal loudness on two speakers will sound like it's coming from the center point between the two speakers. See phantom center.
Play with balance and phase and you can virtually sweep the full line between the two speakers.

If you want to project the sound from a place that's not a midpoint between two speakers, then you could bounce the sound off a wall or ceiling.

And if neither is an option, then you'd have to play with HRTF processing - essentially baking in the sound profile that you would hear if the sound came from where you want it to come.

this becomes very complicated with loudspeaker systems.

... but has been solved more than 30 years ago by Q-Sound. Sting's Soul Cages from 1991 uses it with good results.

 

[staticV3]

... but has been solved more than 30 years ago by Q-Sound. Sting's Soul Cages from 1991 uses it with good results.

No HRTF solution is truly solved without head tracking support and SOFA import capabilities

 

[NTK]

... but has been solved more than 30 years ago by Q-Sound. Sting's Soul Cages from 1991 uses it with good results.

The story from Dr Toole is that Q-Sound was based on binaural processing (cross-talk cancellation).

https://www.avsforum.com/threads/how-to-choose-a-loudspeaker-what-the-science-shows.3038828/page-69#post-57555702

 

[Oddball]

Not to be taken personally in any way shape or form, but I'm afraid my personal experience does not corroborate that statement

On my system if I play the scene from Harry Potter Chamber of Secrets where the professor releases Cornish pixies into the classroom there is a noticeable difference with Sony's 360 Spatial Sound Mapping ON and OFF. I wasn't sure if it was my bias at work so I had my son turn 360 SSM off and on at random times with several different scenes and I was able to pick out SSM being on about 4 out of 5 times correctly. With SSM ON the Cornish pixies sound as if they are in the middle of the room where as with it OFF they sound behind or in front or above but definitely not in the middle of the room. So it seems clear to me that Sony's 360 SSM is in fact creating "phantom" speakers as they claim in their marketing. From what staticV3 indicated I'm guessing there is a fairly complicated processing involved.

The primary reason I am asking this question is because I plan on using REW + a Marantz Cinema 30 + Audyssey MultiEQ to try and create a room correction EQ for my home theater, but now I'm thinking that no matter how good of a room correction one creates it won't match the effect of Sony's 360 SSM technology.

However, as I have said before in other recent posts I have been very wrong of late so it would come as no surprise if I am wrong about this as well and that 360 SSM really is just Snake Oil and good room correction will create an equally good sound.

There are random occurrences of excellence in multi-channel mixes (limited to specific scenes though) and then even more random is how they interact with the given room correction system. So occasionally you might strike the gold.

While your goal might be ultimately achievable in theory, in the current state of HT mixes it is not nowhere near. We kind of have to hope that Atmos mixes will use front wides and will have back and front Atmost channels - regardless of how random and seldom they get used.

 

[thcdru2k]

Its just the science of how we hear. If you have someone on your left yelling at you at 100db it's going to sound like someone is yelling at you at 100db. If you have someone on the left and your right yelling at you at the same time in harmony at 100db it's going to sound like someone is yelling right in front of you at 120db.

 

[Newman]

Now we have the Cornish pixie test! I quite enjoyed that.

 

[A Surfer]

Now we have the Cornish pixie test! I quite enjoyed that.

I certainly didn't see it coming.

 

[Kiko1974]

The story from Dr Toole is that Q-Sound was based on binaural processing (cross-talk cancellation).

https://www.avsforum.com/threads/how-to-choose-a-loudspeaker-what-the-science-shows.3038828/page-69#post-57555702

View attachment 447053

I've only listened to two albums mixed with Q Sound, Madonna's The Inmaculate Collection and Europe's Prisoners In Paradise.
I didn't like It, I think Q Sound sounded phasy, weird. It sounded better for my taste decoded with Dolby ProLogic or ProLogic II.
A few years later Spatializer was released. I had one CD from Telarc, It was mostly classical music. I didn't like It either, It also sounded phasy, but not as much as Q Sound. To me It sounded like "wide stereo" with a phasey and weird/unnatural sound.