Surround Virtualization for Headphones

[MidiMagic]

The scripts I have included here, are for pre encoding music, for playback via headphones without iimpulcifer. You can, of course, go either way. I was going with the pre-encoding approach because it wasn't clear to me how to go beyond 8 channels with impulcifer and I wanted to target 7.1.4 or even 7.1.4.4 etc.

Again my goal is not QUAD reproduction, but a complete 3D immersive sound field with sounds coming above (and even below) the horizontal plane.

This is all part of an ecosystem for immersive music, including immersive up-remix.

7.1.4.4???

The interesting part of human hearing is how the direction of sound is encoded by the ears themselves. The convolutions of the earflaps modify the waveforms of transients to give clues to a single ear for the direction the sound came from. This does not work with tones. And the altered waveforms are ear-specific - they don't transfer from one ear to another.

This is different from the binaural encoding of sound direction. Such encoding depends on differences between arrival times at each ear, relative levels between the ears, head shadowing and its reduction of higher frequencies, and phase changes caused by earflaps. This does transfer from one person to another.

 

[zeerround]

7.1.4, plus 4 speakers on the floor (vs. the 7 speakers at ear level) = 7.1.4.4.

There are other nomenclatures, that say more about the total number of speakers than what "layer" of height they are in, e.g. 22.2 for 24 different speaker locations (in that case only 3 of 22 are "bottom", all in the front).

https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BS.2159-6-2013-PDF-E.pdf

 

[stevendive]

7.1.4.4???

The interesting part of human hearing is how the direction of sound is encoded by the ears themselves. The convolutions of the earflaps modify the waveforms of transients to give clues to a single ear for the direction the sound came from. This does not work with tones. And the altered waveforms are ear-specific - they don't transfer from one ear to another.

This is different from the binaural encoding of sound direction. Such encoding depends on differences between arrival times at each ear, relative levels between the ears, head shadowing and its reduction of higher frequencies, and phase changes caused by earflaps. This does transfer from one person to another.

In a free field the outer ear really only affects localisation at higher frequencies, not LF or MF, as the dimensions of its folds are of a similar size as wavelengths at HF, thus leading to scattering and are indeed different from person to person and ear to ear and help localisation when the head turns in any direction in a quite personal way, hence in binaural personal HRTFs with head tracking generally work better than generic ones.

At LF where wavelengths are many metres, neither outer ear folds nor the head disturb the wave field at all and hearing perception uses the velocity (phase) component where head shadowing is virtually absent at <200Hz. Above 700Hz, we switch to energy difference between the ears for localisation. Luckily, HF localisation approximates to energy localisation when using loudspeakers.

 

[jagxjr15]

FYI: Having done some research (mostly involving "social engineering", about which I will say no more) , I have it on good authority that the SphereAudio feature, supposedly available on StormAudio processors, is indeed vaporware. It was to be a binaural emulator, like the Smyth A8/A16, but, unlike them, not requiring an HRTF measurement/calibration. It has always been "almost ready" but never actually materialized in a product produced for sale, which explains why none of the published reviews of the Storm ISPs have ever reviewed the SphereAudio feature.

 

[jagxjr15]

I was able to find a Smyth A16 bare-bones unit (just the processor, remote, and power cord) for around $2500 US and it's great. It works great with the factory presets (no HRTF measurement) and no head tracking hardware. I just watched a blu-ray movie with great multichannel audio, and the imaging was stable, detailed, and precise. I wish Smyth would sell the A16 like this. It would simplify life for audiophiles who want multichannel audio over headphones, but are intimidated the complexity of the A16 as described in the User Manual.

Oh, and it also works for multichannel audio content from SACDs, etc., which, of course, I also tested. Images that are supposed to circle the room and move behind your head as part of the circling, do that; I remember what it sounded like when I had a 5.1 setup with speakers and with the A8 when it worked, and this replicates that, but without the headtracking headaches I had with the A8.

The head tracking is probably needed for VR or gaming, but it's not needed for films or music and when it fails (which was unpredictable), as it often did for me with the A8, forget it., there was nothing to be done. You would be left wondering...maybe if the stars align tomorrow, it might work for an hour or two...but then the audio image would collapse again. I'm gritting my teeth just thinking about it...

 

[esimms86]

I was able to find a Smyth A16 bare-bones unit (just the processor, remote, and power cord) for around $2500 US and it's great. It works great with the factory presets (no HRTF measurement) and no head tracking hardware. I just watched a blu-ray movie with great multichannel audio, and the imaging was stable, detailed, and precise. I wish Smyth would sell the A16 like this. It would simplify life for audiophiles who want multichannel audio over headphones, but are intimidated the complexity of the A16 as described in the User Manual.

Oh, and it also works for multichannel audio content from SACDs, etc., which, of course, I also tested. Images that are supposed to circle the room and move behind your head as part of the circling, do that; I remember what it sounded like when I had a 5.1 setup with speakers and with the A8 when it worked, and this replicates that, but without the headtracking headaches I had with the A8.

The head tracking is probably needed for VR or gaming, but it's not needed for films or music and when it fails (which was unpredictable), as it often did for me with the A8, forget it., there was nothing to be done. You would be left wondering...maybe if the stars align tomorrow, it might work for an hour or two...but then the audio image would collapse again. I'm gritting my teeth just thinking about it...

You’re extremely fortunate that the factory presets work for you. Of course, you could convert and use an A8 PRIR if you have one. You obviously are not concerned with moving your head while listening.

A PRIR is where the magic starts with the A16. And for many(most?) people, head tracking is also a requirement.

But why didn’t your seller also include the other components with the sale?

 

[jagxjr15]

You’re extremely fortunate that the factory presets work for you. Of course, you could convert and use an A8 PRIR if you have one. You obviously are not concerned with moving your head while listening.

A PRIR is where the magic starts with the A16. And for many(most?) people, head tracking is also a requirement.

But why didn’t your seller also include the other components with the sale?

I don't think I am that unusual in using the default presets of the A16. I have seen many other posts by A16 users who are also foregoing the complex and messy personalization, finding that the factory presets work so well. There is even a 3rd party seller (Home - 3DSoundShop) selling generic PRIRs to users who don't want to buy the speakers and/or do the setup.

Not using head-tracking removes a big source of image instability. The stated objective of head tracking is to improve image stability, but in practice it had the opposite effect for me with the A8, and then you don't need the tracking hardware. In practice you don't move your head much in listening to music or watching films.

Not including the useless hardware, including cables, got me a big discount. And there is no warranty and no manual with my unit. My purchase was not from an individual user, but from a bulk or corporate reseller on eBay. Since I had previously purchased an A8 directly from Smyth, I understood what I was getting. A first-time user would not be confident enough to buy (and should not buy) a bare-bones unit as I did, not having had prior experience with a Smyth processor. And if the unit doesn't work, you need to be able to write off the purchase price as a loss without much financial stress. You gotta have spending money to do this.

 

[esimms86]

I don't think I am that unusual in using the default presets of the A16. I have seen many other posts by A16 users who are also foregoing the complex and messy personalization, finding that the factory presets work so well. There is even a 3rd party seller (Home - 3DSoundShop) selling generic PRIRs to users who don't want to buy the speakers and/or do the setup.

Not using head-tracking removes a big source of image instability. The stated objective of head tracking is to improve image stability, but in practice it had the opposite effect for me with the A8, and then you don't need the tracking hardware.

Not including the useless hardware, including cables, got me a big discount. And there is no warranty and no manual with my unit. My purchase was not from an individual user, but from a bulk or corporate reseller on eBay. Since I had previously purchased an A8 directly from Smyth, I understood what I was getting. A first-time user would not be confident enough to buy (and should not buy) a bare-bones unit as I did, not having had prior experience with a Smyth processor.

I’m not doubting that you thoroughly did your research before making your purchase. You did, after all, clearly state that you previously owned an A8.

And no, you’re not unusual in enjoying the A16 with presets originally made for others. I have and enjoy a couple of “universal PRIRs” purchased from 3D Soundshop. I, however, also have a homemade PRIR capture of my very modest home system, made under suboptimal conditions(i.e., it was made in the early days of my ownership of the A16 and without a partner assisting me). In terms of optimizing an out of your head experience, however, my own PRIR capture is still, F for the fronts, preferable to me. This is why I plan to visit 3D Soundshop later this year to have John go through the painstaking process(3-4 hours) to produce a SOTA PRIR for me. I also continue to wait (for Godot and) Smyth Research to make available the PRIR capture they made for me 5 years ago at CanJam NYC 2017.

While I am very happy to know that you are enjoying your A16, I also have no doubt that your enjoyment would jump up to another level if you were to experience your own PRIR. If you have a useable A8 PRIR I would strongly recommend that you convert it for use with the A16. At the very least, you’d have nothing to lose.

Finally, I would like to point out that the manual is available for download on the Smyth Research web site; a hard copy, in fact, was never supplied to me as a Kickstarter owner.

 

[jagxjr15]

I’m not doubting that you thoroughly did your research before making your purchase. You did, after all, clearly state that you previously owned an A8.

And no, you’re not unusual in enjoying the A16 with presets originally made for others. I have and enjoy a couple of “universal PRIRs” purchased from 3D Soundshop. I, however, also have a homemade PRIR capture of my very modest home system, made under suboptimal conditions(i.e., it was made in the early days of my ownership of the A16 and without a partner assisting me). In terms of optimizing an out of your head experience, however, my own PRIR capture is still, F for the fronts, preferable to me. This is why I plan to visit 3D Soundshop later this year to have John go through the painstaking process(3-4 hours) to produce a SOTA PRIR for me. I also continue to wait (for Godot and) Smyth Research to make available the PRIR capture they made for me 5 years ago at CanJam NYC 2017.

While I am very happy to know that you are enjoying your A16, I also have no doubt that your enjoyment would jump up to another level if you were to experience your own PRIR. If you have a useable A8 PRIR I would strongly recommend that you convert it for use with the A16. At the very least, you’d have nothing to lose.

Finally, I would like to point out that the manual is available for download on the Smyth Research web site; a hard copy, in fact, was never supplied to me as a Kickstarter owner.

Yeah, I was an interested observer on the head-fi.org a16 forum before the first a16s were shipped, waiting for the first Kickstarter buyers to get theirs. And wow I felt sorry for you guys. Smyth would make an announcement and everybody would get excited and parse every infrequent update as if it were some kind of religious tract like a Papal Bull. The first a16s were actually received before the manual was posted/available, so I remember remarking that they would have to somehow reverse engineer the metal lump they received from Smyth to get 'em to work (without a manual!). Then suddenly a manual was posted and the fun began. That was when I tuned out, because of the $4K US price to non-Kickstarter customers. But then it happened that that recent $4K buyers were getting theirs before you Kickstarter buyers who hadn't paid full retail. It's a wonder somebody didn't murder the Smyths when that happened. The natives certainly were restless, to say the least. So I downloaded the first version of the manual when it was posted. I was assuming a printed manual came with the $4K units.

 

[esimms86]

Yeah, I was an interested observer on the head-fi.org a16 forum before the first a16s were shipped, waiting for the first Kickstarter buyers to get theirs. And wow I felt sorry for you guys. Smyth would make an announcement and everybody would get excited and parse every infrequent update as if it were some kind of religious tract like a Papal Bull. The first a16s were actually received before the manual was posted/available, so I remember remarking that they would have to somehow reverse engineer the metal lump they received from Smyth to get 'em to work (without a manual!). Then suddenly a manual was posted and the fun began. That was when I tuned out, because of the $4K US price to non-Kickstarter customers. But then it happened that that recent $4K buyers were getting theirs before you Kickstarter buyers who hadn't paid full retail. It's a wonder somebody didn't murder the Smyths when that happened. The natives certainly were restless, to say the least. So I downloaded the first version of the manual when it was posted. I was assuming a printed manual came with the $4K units.

I can’t confirm or deny whether the $4k units shipped with a manual. I do know that people who purchased an A16 from Gilles Guerin in France did at least receive a link to a proprietary manual written by Gilles and company.

Given Smyth Research’s issues with planning, financing and communications, it’s practically a miracle that any units ever made it out the door. As you know, Kickstarter campaigns are not legally required to result in a shipped project.

 

[zcftr29]

@zeerround - Thank you so much for your work and these scripts. I have tried a few surround2binaural plugins in the past with the hope of converting multichannel music into something I could listen to 'on-the-go' but have never found the results convincing. These are by far the best I have ever heard. I upmixed "Giorgio By Moroder" by Daft Punk, using DTS Neural & Spleeter with some editing in Audition. If you do an ABX comparison in Foobar between the original source and the binaural version, the additional space in the mix is quite impressive I think, and the synths really do seem to move around the rear...

 

[3DSoundShop]

I was able to find a Smyth A16 bare-bones unit (just the processor, remote, and power cord) for around $2500 US and it's great. It works great with the factory presets (no HRTF measurement) and no head tracking hardware. I just watched a blu-ray movie with great multichannel audio, and the imaging was stable, detailed, and precise.

Hello... So you don't have the A16 microphones? Unless you are using HD800 headphones and the included HD800 HPEQ... You are missing quite a bit of the magic of the A16. But even if you are using the included HPEQ... The personalized HPEQ will be a dramatic improvement.

The head tracking is probably needed for VR or gaming, but it's not needed for films or music

I would disagree with this unless you are watching films in complete darkness and don't move your head. For me, the head tracker sells the illusion. It's a not the most attractive part of the system, and my family makes fun of me when they see it. But it does help the brain accept what it's hearing. I personally have had no audio drop outs or errors regardless of my time using the head tracker and A16.

 

[3DSoundShop]

There is even a 3rd party seller (Home - 3DSoundShop) selling generic PRIRs to users who don't want to buy the speakers and/or do the setup.

Hey... That's me. Lol.

You are correct that my PRIRs do work for others... But I think the audience may be somewhat limited. I have engaged with two A16 owners who have trouble with my PRIRs. One hears the LCR channels about 1m above his his head... While all other channels are exactly where they are supposed to be. It's very strange. The next time I'm in the recording studio... I'm going to experiment with my ear level to try to find a position that works for him. Though it is most likely not as simple as that.

I ended up in the recording studio because I didn't like the resulting PRIR "sound" of my living room or the included BBC and Surrey rooms that come with A16. After 100s of hours in the studio and a few A16 PRIR beta testers... my website was born. So far so good.

Not including the useless hardware, including cables, got me a big discount. And there is no warranty and no manual with my unit. My purchase was not from an individual user, but from a bulk or corporate reseller on eBay.

I saw that listing. Passed because of the missing hardware.

 

[jagxjr15]

Awhile back I posted some questions about Auro3D over headphones (SphereAudio) in the "official" Storm Audio ISP Forum on AVS and I finally got an answer. It turns out that SphereAudio has been implemented, but if you have a Mk I ISP (like me) you have to get the firmware updates that enable it, which I plan to do, someday. Meanwhile, John at 3DSoundShop has gotten my A16 into near state-of-the-art trim (or close enough for me, anyway), so that the Storm Audio ISP is no longer an issue. If anybody out there in A16-land wants to get the most from their A16, buy a PRIR or two from John and you will then have the ear of the A16 guru of gurus, who will walk you through any problems or issues you may have -- he is practically, aside from the Smyths, The Authority on all matters A16. He is a recording engineer for hire, and his fees are very modest for the kind of personalized help you will get. You got a question, John's got the answer. And I am NOT a paid endorser, only a paying customer with very high standards when it comes to audio. I am so down with this born-again A16 I got, even James Brown hisself couldn't get me up off it. Now I'm ready to die! I am living at the top of the mountain, and it's great. I have no more hyperboles. 'Nuff said!

 

[marxzua]

There is a surround virtualization product I recently discovered that has not yet been mentioned in this thread.

It's called "Immerse Virtual Studio" by Embody:

https://embody.co/pages/ivs-alan-meyerson
Embody also offers a cheaper product "Immerse Gaming", but that is more specialized for gaming and doesn't work as well for the things I want to do, which is watch media with surround audio through headphones.

I previously used the Waves NX "Virtual Mix Room" VST plugin. Embody "Virtual Studio" works similarly, simulating a set of speakers in a studio. Unlike Waves NX, Embody seems to have measured a real physical studio for its "Virtual Studio".

Like Waves NX, the software is intended for sound engineers to help them mix multichannel audio.

Both products work similarly well to create a sense of directionality in sound, however I like the sound signature of "Virtual Studio" better. Waves NX sounds a little thinner to me in comparison.

The secret sauce is perhaps the set-up process, where the user takes a photo of their ear to create a personalized profile.

It's also interesting that "Virtual Studio" supports up to 14 speakers, including ceiling speakers, making it capable of mixing Atmos soundtracks.

However, the software is not able to decode Atmos tracks itself, and I could not get the "Dolby Access" software to decode to the virtual audio device I use for the "Virtual Studio" software. If any reader has an idea on how to solve this problem, I would be happy to hear it.

If you are interested in testing the software, there is one thing that needs to be mentioned: there are various channel layouts that can be selected for different audio mixing software.

Strangely, none of these layouts seem to match the default Windows 7.1 speaker layout. I had to create a custom channel layout that matches the Windows layout. This is easily done in the software by playing test tones on the individual speakers and arranging the channel layout accordingly.

That's how they are, those posh sound engineers. Looking down from great heights on mere Windows using mortals, if they look up at all from their Macbook Pros...

 

[zeerround]

Sadly I don't see anyway to decode Atmos in software at this time (outside of Dolby stream player, see below). The windows "Atmos" capability is for encoding, vs. decoding.

Atmos decoders have to be licensed (and rigorously tested).

I guess there is existing the dolby stream player. I have it on mac as part of the Atmos encoding suite, but haven't really used it, and don't know if there is a windows version. I don't think there's anyway to get it outside of the $$ encoding suite.

 

[marxzua]

If you already own the Dolby tools, you might be able to virtualize Atmos tracks with this product...

 

[zeerround]

Yeah but I have a Realiser A16 so no need here. Maybe a working combo for others, however.

 

[Phillyfix]

The Fixler Effect!

HELLO!!! THIS WAS MY DAD'S WORKS!!
This is so amazing to find this thread online, talking about my dad's inventions (The Fixler Effect, Quad-4 Stereo, Surround sound headphones (with the first actual physical surround isolated - which prevented that weird "in-head" nasty surround effect).

If I can answer any questions about his inventions or any of that, I would love to! So cool!

 

[Phillyfix]

The idea of EV-4 (not EV-44) came from Jon Fixler's work with headphones. That decoder box he designed for the headphones is actually an adjustable Dyna quad style decoder. I agree that phones can't place sounds all around like you can with speakers but they can still sound rather nice, creating a larger sense of spaciousness than with regular stereo.

HELLO!!! THIS WAS MY DAD'S WORKS!!

This is so amazing to find this thread online, talking about my dad's inventions (The Fixler Effect, Quad-4 Stereo, Surround sound headphones (with the first actual physical surround isolated - which prevented that weird "in-head" nasty surround effect).

I still have these ORIGINAL WORKING ANALOG decoder boxes

If I can answer any questions about his inventions or any of that, I would love to! So cool!