Speaker Angles (option to change angle)

[Esquire Dragonstone]

I would like to ask in 5.1 and 7.1 which speaker angles for Front L and Front R does the HTRF try to simulate ? 22 degree, 30 degree or 45 degree ?
With physical speakers I found while 30 degree sounds great , sometimes with some older games (which were originally programmed with 4 channel setup in mind) 45 degree might possible be more accurate . (Not 100% sure).
Are there any plans to allow the user to change the angle of L/R (simulated through changing parameters in the HTRF funcation) ?
So we could adjust depending on which game we play.

[Esquire Dragonstone]

In OpenAL soft there are different speaker angels depending on the mode selected.
I do not know how XAudio2 deals with this or if has a fixed speaker angle for 5.1 , 7.1

https://github.com/kcat/openal-soft/blob/master/presets/presets.txt

"
square.ambdec
Specifies a basic square speaker setup for Quadraphonic output, with identical
width and depth. Front speakers are placed at +45 and -45 degrees, and back
speakers are placed at +135 and -135 degrees.

rectangle.ambdec
Specifies a narrower speaker setup for Quadraphonic output, with a little less
width but a little more depth over a basic square setup. Front speakers are
placed at +30 and -30 degrees, providing a bit more compatibility for existing
stereo content, with back speakers at +150 and -150 degrees.

itu5.1.ambdec
Specifies a standard ITU 5.0/5.1 setup for 5.1 Surround output. The front-
center speaker is placed directly in front at 0 degrees, with the front-left
and front-right at +30 and -30 degrees, and the surround speakers (side or
back) at +110 and -110 degrees.

"
I think changing the angle in the software would be a great feature, but I really like to know
which angles the software assumes for the HTRF function.

[Esquire Dragonstone]

According to a presentation by Simon Goodwin (Inside Modern Game Audio Engines - Simon Goodwin - ADC21) there is a discrepancy between the ITU 5.1 format and the 5.1 setup that many games expect. Basically in many games for 5.1 front speakers are expected to be loacted at +/-45 degree to the side and surround speakers +/- 135 degree. However in the same presentation for 7.1 the front speakers are now located +/- 30 degree and back speakers at +/- 150 degree.

[Esquire Dragonstone]

I think this is an area where the Spatial Audio Card Software combined with using Headphones is at huge advantage compared to loudspeakers if one could change angels of the setup in the software. Easily switching between angles depending on if the user watches a movies, plays a game etc...

[Esquire Dragonstone]

Since the angle of the loudspeaker is a parameter for the HRTF function this could probably be easily realized in the software.

[movision]

Hi Chri,
sorry for the delayed answer.
We (the SSC) offer real measured loudspeaker environments which make our binaural experience pretty realistically. The disadvantage is, it is as it is. We cannot move the virtual loudspeakers (HRTFs) but we can offer different environments and adjustment parameters for, what we do. And most measurements are +/- 30 Degree. From a professional point of view, I can tell you, a 30 degree. each side = 60 degre in total is the standard, also in ITU stereo and 5.1. Surrounds are good from +/-110 to +/- 135. But however, it's an ongoing discussion;)
Best,
Tom
(Support)

[Esquire Dragonstone]

Thanks Tom. Unfortunately it seems that some API do not care much about ITU and assume corner placement. According to "Inside Modern Game Audio Engines - Simon Goodwin - ADC21" "Microsoft(XAudio, XBOX and Windows) Sony, (Multistream, PS3) Apple (OpenAL) all assume that front and rear pair speakers are placed at 90 degree."


If you consider panning just between left and right front let´s say there is a sound source at 30 degree angle. If the API assume that the left speaker is 45 degree it will start to pan between left, right speaker to output the sound as if it were at 30 degree, Now with a setup for 30 degree the sound should only come from the left speaker, if the right one is active the sound should theoretically now shift to the right and be heard as if coming from the wrong direction. This throws of the accurate locating of sounds that some games make use of.

I think at 7.1 the situation is different so I think it is a lot preferable over 5.1

There are the surrounds located at 7.1 ?


Have a great day
Chris

PS:
I am trying to find information of where different API assume the speaker default location and I might update this threat with information that I find.
If you have any information of where Miles Sound System (used for example in Apex Legends) and WWise assumes the location for default speakers please let me know.

[movision]

Hi Chris,
sorry again for the tremendous delay. We're just busy here with a lot of tasks;)

Currently, I have no news for you, but I'm pretty sure we will pick up this ball in the future and will go through all this step by step.

Because the SSC currently takes ready-rendered stereo, 5.1, and 7.1 mixes, we don't have to care about this angle discussion. But in our Pro application, we do care about it and we also do 'translations' of angles. So finally we will offer solutions if we make a step with SSC into that direction.

Best regards,
Tom

[Esquire Dragonstone]

Tom I think there might be an easy way to solve the issue of the speaker locations.
How about adding a 4.0 option with all speakers in the corner?
If we had the option to choose a 4.0 quadrophonic layout or a 5.1 with the speaker located at (45, 135.....angles) when we could just select this for some games.
Since some games do assume a quadraphonic layout with speakers in the corner , while other games do go more for an ITU layout.
Also some games have a 4.0 option.
By adding one 4.0 option with speakers in the corners or a 5.1 with 4 of the 5 speakers in the corners, it would improve the application´s performance for many games.

Wishing you a fine holiday and a good start into the new year

[Esquire Dragonstone]

Originally posted by movision:

Hi Chris,
Because the SSC currently takes ready-rendered stereo, 5.1, and 7.1 mixes, we don't have to care about this angle discussion.

With 5.1 sound API use a quad Layout (like in quadrophonic music ) instead of ITU.

If the game rendered the 5.1 mix with an API which assumes a quad layout (speakers in the corners, 45, 135 degrees) + center speaker and HTRF is applied assuming an ITU Layout , there might be issues with accuracy. That is why a propose a toggle for 5.1 between HTRF for Quad and ITU.

Luckily 7.1 is a piece of cake in comparision as the speaker layout is much more similar between cinema and gaming.

[Esquire Dragonstone]

Software is amazing for 7.1

[Ferfs]

I'm not expecting to be able to change speaker angles inside the app, but if the loading of the main page where we see the speakers engaged is any indication, the app definitelly have much more than 7.1 speakers to virtualize. I think what could be possible to do would be to choose which speaker to play in a set, for example, Left and Right could be played at Left C and Right C, closer to the center, and anchor better to smaller screens like notebooks, or copy surround material from 5.1 to the SI and RE speakers together with the SR's, maybe even with the Center SR, all atenuated accordinglly, still following ITU's reccomendations. It's only a little sad to see that 5.1's surrounds share 7.1's rear surrounds, instead of been it's own thing. But what's even more fascinating is the hidden RE speakers: what were those supposed to be?

[Esquire Dragonstone]

Originally posted by Ferfs:

I'm not expecting to be able to change speaker angles inside the app, but if the loading of the main page where we see the speakers engaged is any indication, the app definitelly have much more than 7.1 speakers to virtualize. I think what could be possible to do would be to choose which speaker to play in a set, for example, Left and Right could be played at Left C and Right C, closer to the center, and anchor better to smaller screens like notebooks, or copy surround material from 5.1 to the SI and RE speakers together with the SR's, maybe even with the Center SR, all atenuated accordinglly, still following ITU's reccomendations. It's only a little sad to see that 5.1's surrounds share 7.1's rear surrounds, instead of been it's own thing. But what's even more fascinating is the hidden RE speakers: what were those supposed to be?

Honestly I think on PC ITU will be getting a lot less useful.
Many Video Streaming Services now only offer Stereo Sound instead of Surround Sound on Windows. The new AppleTV app being an exception.
For Gaming it seems like many games do not expect speakers to be located at ITU angles.
Some games do seem to assume a Layout with Speakers in the corners.
That´s one of the reason I prefer to use 6 loudspeakers or 7 while gaming.

For less than 6 main speakers (excluding subwoofer) it would be very useful to have an ITU and a QUAD Gaming mode toggle.