Recording Impulse Responses for Speaker Virtualization
Apr 1, 2024 at 2:16 PM Post #1,816 of 1,914
That’s awesome news. I can’t test it for a few days myself but came across it on Reddit. Does it decode on the fly or do you have to encode the audio separately ?

Also he wrote this
“This also only works with e-ac3+joc not trueHD+”

@musicreo Did you try trueHD?

Yes, only DD+ (E-AC3) works. There is one program that does the decoding on the fly and visualize what channels and audio objects are active and another one that converts the audio.
 
May 6, 2024 at 2:45 AM Post #1,817 of 1,914
Guys i would like to suggest you, if you can't afford the hd800s, there's the hifiman edition XS that's 400 bucks (i even found it 300 euros on A warehouses) and it's a very good planar headphone that have almost the same soundstage and imaging, the bass are also great to be a planar (bass sound is better than the hd660s) and works great with hrir and impulcifer

the only downside is that there's almost no clamping so if you have a tiny head like me you absolutely need an additional headband like the geekria one
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Jul 6, 2024 at 3:48 PM Post #1,818 of 1,914
Quick question. Is it normal to need to have the volume much higher with our hrir’s to get the same level of volume as normal stereo or surround? I’m kinda worried I might be putting the volume too loud but I enjoy the surround sound and it’s only good when it is loud.
 
Jul 7, 2024 at 9:58 AM Post #1,819 of 1,914
Quick question. Is it normal to need to have the volume much higher with our hrir’s to get the same level of volume as normal stereo or surround?
If you want to prevent clipping the Brirs must be below 0db in EQ-APO. For surround this is the sum of all channels and hence the hrirs are on low volume level. But usually it is very rare that all surround channels are at high level at the same time and the amplification can be set to high value.

The difference for my own measurement compared to "normal" stereo listening is close to 20db in EQ-APO!
 
Jul 7, 2024 at 10:26 AM Post #1,820 of 1,914
Quick question. Is it normal to need to have the volume much higher with our hrir’s to get the same level of volume as normal stereo or surround? I’m kinda worried I might be putting the volume too loud but I enjoy the surround sound and it’s only good when it is loud.
you mean the db level inside eqapo? this should be low as possible, i keep it 6db though, it's very difficult to hear clip, you should go over 10db to start hearing clipping
 
Jul 7, 2024 at 3:56 PM Post #1,821 of 1,914
Yeh eqapo or just generally it’s quite a bit louder db than if I was to listen to normal stereo. Was thinking because it’s virtual surround it might be tricking my brain and I’m listening to movies games music too loud and it will damage my hearing.
 
Jul 10, 2024 at 11:00 AM Post #1,822 of 1,914
Does anyone use their brir for surround. Also using hesuvi with VB audio cable and also use a Dolby atmos tv connected with hdmi?

I am definitely getting proper height channels and full atmos. Watching the movie 1917 and planes flying over head is exactly how planes flying overhead in real life sound like. That’s one example, every movie in atmos sounds life like. Blade runner advertisements are above and in the right direction giving proper sense of scale.

I’m using a hacked Dolby driver and home theatre v4 I have the files to send. And you also need Dolby access to output pc movies in Dolby atmos to the tv which the tv recognises. This is definitely not a placebo.

I know it’s a long shot that everyone will be using a similar setup, but I want someone else to try it out so they can confirm to everyone else.
 
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Jul 10, 2024 at 6:30 PM Post #1,823 of 1,914
I am definitely getting proper height channels and full atmos. Watching the movie 1917 and planes flying over head is exactly how planes flying overhead in real life sound like. That’s one example, every movie in atmos sounds life like. Blade runner advertisements are above and in the right direction giving proper sense of scale.
I tried to find information about Dolby Atmos concerning something I seem to remember reading a long time ago, but I can not find or confirm it so I could be completely wrong. Hopefully someone else knows?
So what I thought to have read was something along the lines of this:
If Dolby Atmos is rendered to a speaker layout without height speakers (and also without ceiling-reflecting speakers), say 7.1, then the part of the audio that was supposed to go to the height speakers is (or can be) processed with (using a generic hrtf) the difference between the hrtf from elevated sound and the hrtf from horizontal sound (from the same or not too far off azimuth angle). So that could give a feeling of height/elevation to that part of the audio.
If that is true then that effect could/would work the same when listening to that 7.1 rendering of Dolby Atmos via 7.1 virtual speakers rendered by HeSuVi. (I assume that is what you are doing?) [Edit: Actually I don't understand what your set-up is at all, and how your "atmos tv" and hdmi is used in combination with HeSuVi???]
In that case of course your personal hrtf (that is implicitely present in your personal measured hrir) is used for the horizontal positioning of the virtual speakers, but the height sensation is not (fully) in accordance with your personal hrtf, but with a combination of your personal hrtf and the used generic hrtf.

But that is something different of course from having a "real" 7.1.4 (for example) rendering over 7.1.4 virtual speakers.

This is definitely not a placebo.
Just like for example seeing real speakers when listening to virtual speakers can influence the experience, so can for example knowing where the sound of airplanes usually comes from influence that part of the experience. So that still could be a (contributing) factor.
 
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Jul 11, 2024 at 1:32 AM Post #1,824 of 1,914
I tried to find information about Dolby Atmos concerning something I seem to remember reading a long time ago, but I can not find or confirm it so I could be completely wrong. Hopefully someone else knows?
So what I thought to have read was something along the lines of this:
If Dolby Atmos is rendered to a speaker layout without height speakers (and also without ceiling-reflecting speakers), say 7.1, then the part of the audio that was supposed to go to the height speakers is (or can be) processed with (using a generic hrtf) the difference between the hrtf from elevated sound and the hrtf from horizontal sound (from the same or not too far off azimuth angle). So that could give a feeling of height/elevation to that part of the audio.
If that is true then that effect could/would work the same when listening to that 7.1 rendering of Dolby Atmos via 7.1 virtual speakers rendered by HeSuVi. (I assume that is what you are doing?) [Edit: Actually I don't understand what your set-up is at all, and how your "atmos tv" and hdmi is used in combination with HeSuVi???]
In that case of course your personal hrtf (that is implicitely present in your personal measured hrir) is used for the horizontal positioning of the virtual speakers, but the height sensation is not (fully) in accordance with your personal hrtf, but with a combination of your personal hrtf and the used generic hrtf.

But that is something different of course from having a "real" 7.1.4 (for example) rendering over 7.1.4 virtual speakers.


Just like for example seeing real speakers when listening to virtual speakers can influence the experience, so can for example knowing where the sound of airplanes usually comes from influence that part of the experience. So that still could be a (contributing) factor.
Dolby Atmos is 3D object oriented format: it takes a fixed number of channels and objects to simulate a 3D space, and then map that to whatever speakers/headphone you have. In order to use Atmos, you need both the speaker setup, the material, and a system that has the decoder.

Consumer Atmos tracks for home movies have a meta-data stream (Joint Object Coder) that has up to 16 dynamic channels (channels or objects for tracking), then also a fixed surround stream (that’s either static 5.1 or 7.1). If you stream a movie in Atmos, the static stream is 5.1 Dolby Digital Plus (and if your system doesn’t support Atmos, it will see it as a Dolby Digital Plus track). If you’re watching a UHD disc, the static stream is 7.1 TrueHD (that a non-Atmos system sees as TrueHD. Apple Music now has some songs in Atmos (since their headphones use Atmos for their 3D rendering. The surround stream Apple uses for lossless is their ALAC (so Atmos JOC stream is within that track).

For a headphone system, if it doesn’t have the Atmos decoder in the mix, then it would just be seeing the 5.1/7.1 surround. And it would be applying its own process for binaural overhead effects.
 
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Jul 11, 2024 at 2:02 AM Post #1,825 of 1,914
It’s very very convincing I know it’s mixed to give me the height effect because I never recorded any height speakers. But it sounds as good as my other speakers in front, back or side etc.

Watching new ghostbusters last night and ever spark, crack, creek, people, footsteps basically all sound had their own position in real space. Like you are in that place yourself. Above sounds make your hair stand up!!!

The reason I’m giving my full setup is because I’m not sure exactly what one or a combination of things I have done to get this level of immersion but I need someone else to try it too. May not need to have a tv with Dolby atmos could be any device to decode the atmos.
 
Jul 11, 2024 at 6:13 AM Post #1,826 of 1,914
Dolby Atmos is 3D object oriented format: it takes a fixed number of channels and objects to simulate a 3D space, and then map that to whatever speakers/headphone you have. In order to use Atmos, you need both the speaker setup, the material, and a system that has the decoder.

Consumer Atmos tracks for home movies have a meta-data stream (Joint Object Coder) that has up to 16 dynamic channels (channels or objects for tracking), then also a fixed surround stream (that’s either static 5.1 or 7.1). If you stream a movie in Atmos, the static stream is 5.1 Dolby Digital Plus (and if your system doesn’t support Atmos, it will see it as a Dolby Digital Plus track). If you’re watching a UHD disc, the static stream is 7.1 TrueHD (that a non-Atmos system sees as TrueHD. Apple Music now has some songs in Atmos (since their headphones use Atmos for their 3D rendering. The surround stream Apple uses for lossless is their ALAC (so Atmos JOC stream is within that track).

For a headphone system, if it doesn’t have the Atmos decoder in the mix, then it would just be seeing the 5.1/7.1 surround. And it would be applying its own process for binaural overhead effects.
I sort of know all that, but that is not contradicting the additional feature that I mentioned (that would be intended for a real <=7.1 loudspeaker setup but should then also work for a virtual 7.1 loudspeaker setup).
By the way about the sounds in the objects: are they audible if the track is played with a normal Dolby Digital or TrueHD decoder (and "moved" out of there to be panned to other speakers when played by an Atmos decoder), or are they simply not audible when played by a normal Dolby Digital or trueHD decoder? I would hope the former, otherwise some sounds would simply be missing then! And in the case that it is the former then it could have been done in such a way that the sounds intended to be elevated are already processed with that hrtf-difference I talked about, which could (and should) be undone by an Atmos decoder.
 
Jul 11, 2024 at 6:22 AM Post #1,827 of 1,914
The reason I’m giving my full setup is because I’m not sure exactly what one or a combination of things I have done to get this level of immersion but I need someone else to try it too. May not need to have a tv with Dolby atmos could be any device to decode the atmos.
I really have no clue what your setup is in terms of signal path, the order in which it goes through what. For my idea to be possible you should be listening to a 7.1 rendering over a 7.1 virtual loudspeakersetup, without any additional processing after that. I now think that is probably not what you are doing because I don't see how a [Edit: Atmos-]tv and hdmi would fit into that.
 
Jul 11, 2024 at 6:42 AM Post #1,828 of 1,914
I sort of know all that, but that is not contradicting the additional feature that I mentioned (that would be intended for a real <=7.1 loudspeaker setup but should then also work for a virtual 7.1 loudspeaker setup).
By the way about the sounds in the objects: are they audible if the track is played with a normal Dolby Digital or TrueHD decoder (and "moved" out of there to be panned to other speakers when played by an Atmos decoder), or are they simply not audible when played by a normal Dolby Digital or trueHD decoder? I would hope the former, otherwise some sounds would simply be missing then! And in the case that it is the former then it could have been done in such a way that the sounds intended to be elevated are already processed with that hrtf-difference I talked about, which could (and should) be undone by an Atmos decoder.
I'm just guessing, but between the cone of confusion(to each sides), the fact that center elevation is a FR thing, and extra clues about where the sound should(like helicopters and planes being fully expected to be heard above head by the brain), I would expect a lot to "work" in practice without actual elevated speakers. It's still most likely going to be a different experience because not everything can be done for perceived elevation with a generic psychoacoustic profile. But I don't see why not, at least for some scenarios and some listeners.
I'm a bad example to talk about my experience here because I tend to perceive too many things above me that shouldn't be there in the first place(it's been my life with headphones and IEMs already, with stuff going straight up instead of in front of me), and it's to a point where I don't use elevated speakers on the A16 because in my mind it feels like I'm going back to less realistic center channel localization. It's very strange, and objectively I know I'm wrong about it, but I feel how I feel. Let's call it the headphone trauma^_^.
 
Jul 11, 2024 at 7:03 AM Post #1,829 of 1,914
My tv is the listening device that’s needed for vbaudio cable to work with hesuvi. That’s the only way I’ve got hesuvi to work even before the Impulcifer thing. Which is why the hdmi is important.

when I set up Dolby access (which has a toggle to upmix to height channels) Dolby atmos is triggered on my tv. But just using that wasn’t enough, it was good but when I used the hacked driver to put Dolby into my lg tv driver on pc that’s when it all sounded surreal. I should mention my headphones are connected to the back of my tv through 3.5 mm jack. Connecting headphones to pc doesn’t activate Dolby atmos or is not compatible with Dolby access.

Another thing is I’ve changed all audio extensions on cru (custom resolution utility) as 8 channels or more.

It’s not just height though. As I said before every object has its own space and reverb. There’s a scene in ghostbusters where smoke is released from a cube and it drops and spreads to the floor moving out and it sounds like it’s moving in real time in my room. No individual speakers just natural sound travelling. The sense of immersion each room feels the right size. Outdoors feels and sounds outdoors. Very difficult to put into words.
 
Jul 11, 2024 at 7:06 AM Post #1,830 of 1,914
Just like for example seeing real speakers when listening to virtual speakers can influence the experience, so can for example knowing where the sound of airplanes usually comes from influence that part of the experience. So that still could be a (contributing) factor.
The funny thing is I was testing my setup and was on my phone with this playing in the background. The plane moving above took me by surprise so take that as it is. I don’t think the knowing what object is making what sound is playing too much in this situation
 

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