Jul 28, 2019 at 8:37 PM Post #181 of 291
Impressions of Yarra 3DX surround capabilities

TLDR:
  • Multichannel PCM doesn’t work at all for surround whether via usb or HDMI. You have to feed it Dolby Digital 5.1 for surround (with the exception of pre-binauralised content, in which case see last bullet point
  • At near field distances, the far field surround mode processing of Dolby Digital 5.1 is more noticable and convincing and for me closer to the experience of a true setup.
  • In terms of DD5.1 surround effect (rear cues in particular), although good, it still feels / sounds more like processed virtual surround than it does a true setup.
  • Pre-binauralised content fed to the Yarra in 2.0 stereo requires the Yarra’s surround mode to be in effect (i.e. double HRTF) in order to be convincingly enveloping and positional cues to be accurate. Unfortunately doing this also destroys the sound quality / fidelity.

Elaboration:

Multichannel PCM

USB from PC only registers the Yarra in the Windows sound manager as a 2.0 stereo device.

HDMI from PC shows the Yarra in the sound manager as a surround capable device with various multichannel configurations up to 7.1 selectable. . . but none of them result in any output over the surround channels.

Dolby Digital 5.1

When DD5.1 works on the Yarra, the Surround Effect can be very good but produces a similar effect to headphone VSS and as such will be limited by the mixing of the source content and the limitations of VSS. Rear channel sounds will be appreciable but feel somewhat artificial/processed, particularly in videogames where rear cues are often boosted in comparison to front cues. In terms of rear and side cues, it is not noticably better than the best headphone / virtual surround combos. The advantage it does have over headphones however is its installation position as physical source of the sound either beneath or close to the TV / monitor screen, thereby avoiding the perceived “in your head” disconnect you can get with headphones clamped to your ears in comparison to the physical distance between you and the speakers and the Tv or monitor. So I guess in that sense cues from the front/center tend to feel like they have more depth and distance (but then again that would likely be the case with any physical speaker setup).

Near field vs Far field Surround modes

While I am not familiar with the exact mechanics behind Yarra’s surround field processing and output, I was under the impression that the bundle of sound beams would be output in a wider, more diffuse pattern in near field mode in order to create an enveloping surround effect for the close range user while the far field bundle of beams would be narrower and more focused at point of origin in order to preserve equivalent separation and surround effect at farther distances where the effect created by the near field mode would have otherwise dissipated due to being much wider and more diffuse to begin with.

Regardless, in practice (at least to my ears and no matter what ambient preset or HRTF model I use), at near field range the surround effect is much more apparent, enveloping and convincing if using the far field mode instead. . .!?
I have yet to try in a different room which would allow me to test both near and far field modes at a far field listening distance. Will update if I get a chance.


Binaural Content and Pre-binauralised surround mixes using pre-existing virtual Virtual Surround sound solutions.

In the few instances I have seen this previously discussed by commenters on forums, the big concern appeared to be ensuring that Yarra’s surround mode could be turned off to avoid double HRTF or the re-binauralisation of already binauralised content.

Well, in my testing of specifically binaural tracks like “virtual barbershop” and also discrete multichannel content binauralised into headphone virtual surround (via Dolby Atmos for Headphone, DTS Virtual X and Creative SBX surround) then fed to the Yarra, the Yarra’s surround effect needs to be set to “ON”, presumably to detect and exploit the various cues in the pre-binauralised 2.0 stereo. While the mechanics behind it may well be different, in terms of results, it reminds me of using Dolby Pro Logic or DTS Neo on surround content that has been downsampled into 2.0 stereo. You won’t get much in the way of surround effect from it unless you use something to intelligently upmix back into some semblance of the original surround.

In every instance and sample content I tried, setting the Yarra to stereo just meant the cues and depth were all over the place, with rear and sides totally off, whether in near or far field modes. Setting the Yarra to surround on the other hand, positioned the cues exactly where they were supposed to be.

If you want to try this out, just go to the “virtual barber shop” binaural demo on YouTube. Listen to it a couple of times using the best pair of headphones you have, familiarising yourself with the positional cues. Now try that same content with the Yarra. In stereo mode, the bits where the barber is behind you and cutting the hair around your ears sounded markedly in front of me with no illusion of rear placement, rather than cutting my hair, it sounded like he was cutting somebody else’s hair a foot or two in front of me. Setting the Yarra to surround mode fixed this and the cues were back to where they should be. Unfortunately however, doing this also wrecks the sound quality. So at present, the choice for such binaural content is either inaccurate directional positioning of cues with OK sound quality or good positioning but terrible sound quality.
 
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Jul 28, 2019 at 11:02 PM Post #182 of 291
@Dr AIX
Dr. Waldrep, are you able to provide any details regarding the 9 HRTF presets available on the Yarra when it is fed with Dolby Digital processing? There is currently no information available in the official support literature.

I assume they are based on different dummy head models and it would certainly be useful to know of any available measurements / characteristics for each preset (for example, head circumference, inter-aural arc etc.).

When the product was still in development you shared some characteristics of modes available at the time using terms such as “ambient on / off” - is this is some kind of room / reverb effect? - and “masking / no masking” - I would be grateful if you could explain this term.

Many thanks
 
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Jul 28, 2019 at 11:12 PM Post #183 of 291
Dolby Digital 5.1
Do you, or anyone else, know what is the highest bitrate Dolby Digital (normally the max is 640 kbit/s I think) that the Yarra accepts? And maybe if it can accept Dolby Digital Plus (which supports up to 6.144 Mbit/s I think, but I maybe that is only for more than 5.1 channels)?
 
Jul 28, 2019 at 11:26 PM Post #184 of 291
What are the general thoughts of those who got the Yarra?

Is the unit what you were hoping or a bit underwhelming?
 
Jul 29, 2019 at 1:03 AM Post #185 of 291
Do you, or anyone else, know what is the highest bitrate Dolby Digital (normally the max is 640 kbit/s I think) that the Yarra accepts? And maybe if it can accept Dolby Digital Plus (which supports up to 6.144 Mbit/s I think, but I maybe that is only for more than 5.1 channels)?
It can’t decode DD+ natively per se but AFAIK, it should be able to extract vanilla DD5.1 from a DD+ feed as DD+ is supposed to offer a degree of compatibility with devices that can only decode DD5.1. You just wouldn’t get the enhanced spec / benefits that DD+ offers over vanilla DD5.1.

The only way to know for sure is to feed/pass DD+ to the Yarra directly and see what happens. If the light turns blue, it’s receiving and decoding vanilla DD of some sort. You could just test some surround content in that instance to see if it’s DD2.0 or 5.1.

In marketing material, Comhear said they would look into licensing / adding support for further surround formats / codecs in the future via FW update but I wouldn’t hold my breath, particularly if they don’t go the commercial mass market route.

So, as of now, the only (potential) support that is unclear is multichannel PCM.
Mark Waldrep said it wasn’t supported in forum posts (and right now, it clearly isn’t) but the subsequent spec / feature list in a later / more recent email update from Comhear to backers (a month or two before shipping), lists multichannel PCM as being supported. . . Clerical error or is it supposed to implemented either now (in which case it’s broken) or later (in which case development must be behind schedule)?

As for DD5.1 bitrate, don’t know. Presumably the highest allowed by vanilla DD 5.1.
 
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Jul 29, 2019 at 11:58 AM Post #186 of 291
What are the general thoughts of those who got the Yarra?

Is the unit what you were hoping or a bit underwhelming?

I have had the Yarra for about ten days and have tested it twice
With optical and aux
First of all it feels like a beta test product still needs a number of firmware updates
Especially a very underwhelming sub woofer
This is a passive sub with no ability to alter the crossover frequency so is a nightmare
to wake-up from standby (orange) to active (green)
Mostly going back to standby even though the right level of sound and bass is playing
For me this is a major issue as without the sub active the sound is thin and almost metallic
I am hoping this is going to be sorted with firmware update
To me the subwoofer is not capable of supporting the soundbar , and should have been supplied with a powered sub
Will try out in couple of days with a powered sub see if this makes a huge difference
Until this is solved the jury's out for me as I have to keep taking cinch sub cable out restarting the Yarra to wake it up
Has anybody else experienced this problem
Any advice would be great as to how I wake the sub
 
Jul 29, 2019 at 12:27 PM Post #187 of 291
I have had the Yarra for about ten days and have tested it twice
With optical and aux
First of all it feels like a beta test product still needs a number of firmware updates
Especially a very underwhelming sub woofer
This is a passive sub with no ability to alter the crossover frequency so is a nightmare
to wake-up from standby (orange) to active (green)
Mostly going back to standby even though the right level of sound and bass is playing
For me this is a major issue as without the sub active the sound is thin and almost metallic
I am hoping this is going to be sorted with firmware update
To me the subwoofer is not capable of supporting the soundbar , and should have been supplied with a powered sub
Will try out in couple of days with a powered sub see if this makes a huge difference
Until this is solved the jury's out for me as I have to keep taking cinch sub cable out restarting the Yarra to wake it up
Has anybody else experienced this problem
Any advice would be great as to how I wake the sub
Sub signal dropping out and the sub going into to standby appears to be a common problem. I had no problems until the latest firmware at which point drops started happening and increasing in frequency the more I used it. Sometimes reconnecting the connector cable would wake it back up, other times, I would need to cold reboot the Yarra itself.
Getting the sub to ‘engage’ at the start of a session was always an issue for me even prior to the update but only a very minor one, just fiddle with the volume slider in the Yarra app would always wake it up. This still works at the beginning of a session but as previously mentioned, it doesn’t always wake it up when it goes to sleep mid-session.
Apparently Comhear have acknowledged the issue and will be releasing a firmware update in the next week or two although I doubt that will include crossover adjustment.
 
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Jul 29, 2019 at 12:53 PM Post #188 of 291
Sub signal dropping out and the sub going into to standby appears to be a common problem. I had no problems until the latest firmware at which point drops started happening and increasing in frequency the more I used it. Sometimes reconnecting the connector cable would wake it back up, other times, I would need to cold reboot the Yarra itself.
Getting the sub to ‘engage’ at the start of a session was always an issue for me even prior to the update but only a very minor one, just fiddle with the sub’s volume slider in the Yarra app would always wake it up. This still works at the beginning of a session but as previously mentioned, it doesn’t always wake it up when it goes to sleep mid-session.
Apparently Comhear have acknowledged the issue and will be releasing a firmware update in the next week or two although I doubt that will include crossover adjustment.
Thanks do you think if I used powered subwoofer with adjustable crossover it will give a far better bass support to the Yarra and improve the overall sound

Ideally one I can keep permanenly powered on with no standby

I personally think the one supplied is underpowered passive ported sub and is a very low quality subwoofer which needs to be upgraded to
something far more powerful

Do you agree
 
Jul 29, 2019 at 1:49 PM Post #189 of 291
Thanks do you think if I used powered subwoofer with adjustable crossover it will give a far better bass support to the Yarra and improve the overall sound

Ideally one I can keep permanenly powered on with no standby

I personally think the one supplied is underpowered passive ported sub and is a very low quality subwoofer which needs to be upgraded to
something far more powerful

Do you agree
Dunno tbh. Subs are not really my area of expertise or experience and for my use case (medium sized bedroom), setting sub volume to between 85% and 100 and engaging bass boost if necessary (depending on the content) has been sufficient for me.

It’s worth a try, I guess, if you have a spare one lying around, but if not, then I’d give it a couple of weeks to see what Comhear can do for firmware before spending any more money. They are well aware of complaints of low sub volume too.
 
Jul 29, 2019 at 2:02 PM Post #190 of 291
Hi all,

First and long post!!

UK backer received mine cpl of weeks ago but was a bit I'll to do much testing initially.

Subwoofer is pretty poor, I was also getting the issues with it triggering to on but the first firmware update mostly fixed it and then I swapped it for a powered Yamaha I had in the loft and then to a slightly smaller Harman Kardon with a better lead and it kicks in straight away and makes a much fuller sound so if you have a spare sub give it a blast!!

Mainly using far but also using near on headshape 7 which seems to like my block shaped head haha and when working well you can get good positional audio from binaural recording or a binauralised output from the Xbox but it is getting it to work fine...

I am on latest firmware and can agree with lpcm statement above in regards to no center channel being mixed in to the sound, can hear surround effects but no center channel/voices.

This has been using my Nvidia Shield, the only counter to that would be Amazon Prime which is 5.1 and does get all channels mixed and in surround without the blue light confirming DD on the unit.

Any other output on the Shield (mainly Kodi/Emby) to 7.1 channels so I could send decoded TrueHD etc is missing channels which is super annoying after the updates and the fact it is 2019 so regular DD 5.1 is so limited in bitrate etc we really need LPCM to be working. I am pretty sure I was still at school in 1996 when I got my first DD supporting Amp and speakers so supporting something a bit newer is really needed!!

This brings to my next and main issue and that is audio dropouts on HDMI, after Atmos was advertised then confirmed as not supported natively enquired about using the Atmos output to HDMI headset on Xbox/Win10 on Kickstarter and was advised that would be a good way to still get 3d audio out of the device (Think it was Dr AIX that replied at the time) but it just cuts out all of the time, when it is working it is awesome but cannot handle the dropouts. These don't just happen on the Xbox but any HDMI device I use, a cold reset normally resolves for a random period of time except the Xbox which goes dropout crazy!!

This does not happen on Toslink but the sound quality is degraded which I guess is that it drops to a 16bit @ 44khz DD 2.0 stream.

Does anyone have a HDMI 2.0 Win10 pc that can test HDR playback with Atmos for headsets enabled?

Wondering if that part of it is Xbox related as the cold reset fixes on other devices but not when in game on the Xbox. Looking to get a little NUC or something if it can do HDR and Atmos with the Yarra.

Also, switching from Surround to Stereo is mental, you can save profiles for each but it does not respect the setting so if I ever need to change it have to open the app on my phone or plug it in to the laptop instead of press a button on the remote.

I have no doubt the unit can do as advertised regarding the beamforming and surround effect and when it works it is great but it currently is a little rough around the edges for usability and reliability.

Will post back further updates and results after any new firmwares and also happy to do any testing if anyone has requests or has solved the HDMI dropout issue :)
 
Jul 29, 2019 at 3:11 PM Post #191 of 291
Hi all,

First and long post!!

UK backer received mine cpl of weeks ago but was a bit I'll to do much testing initially.

Subwoofer is pretty poor, I was also getting the issues with it triggering to on but the first firmware update mostly fixed it and then I swapped it for a powered Yamaha I had in the loft and then to a slightly smaller Harman Kardon with a better lead and it kicks in straight away and makes a much fuller sound so if you have a spare sub give it a blast!!

Mainly using far but also using near on headshape 7 which seems to like my block shaped head haha and when working well you can get good positional audio from binaural recording or a binauralised output from the Xbox but it is getting it to work fine...

I am on latest firmware and can agree with lpcm statement above in regards to no center channel being mixed in to the sound, can hear surround effects but no center channel/voices.

This has been using my Nvidia Shield, the only counter to that would be Amazon Prime which is 5.1 and does get all channels mixed and in surround without the blue light confirming DD on the unit.

Any other output on the Shield (mainly Kodi/Emby) to 7.1 channels so I could send decoded TrueHD etc is missing channels which is super annoying after the updates and the fact it is 2019 so regular DD 5.1 is so limited in bitrate etc we really need LPCM to be working. I am pretty sure I was still at school in 1996 when I got my first DD supporting Amp and speakers so supporting something a bit newer is really needed!!

This brings to my next and main issue and that is audio dropouts on HDMI, after Atmos was advertised then confirmed as not supported natively enquired about using the Atmos output to HDMI headset on Xbox/Win10 on Kickstarter and was advised that would be a good way to still get 3d audio out of the device (Think it was Dr AIX that replied at the time) but it just cuts out all of the time, when it is working it is awesome but cannot handle the dropouts. These don't just happen on the Xbox but any HDMI device I use, a cold reset normally resolves for a random period of time except the Xbox which goes dropout crazy!!

This does not happen on Toslink but the sound quality is degraded which I guess is that it drops to a 16bit @ 44khz DD 2.0 stream.

Does anyone have a HDMI 2.0 Win10 pc that can test HDR playback with Atmos for headsets enabled?

Wondering if that part of it is Xbox related as the cold reset fixes on other devices but not when in game on the Xbox. Looking to get a little NUC or something if it can do HDR and Atmos with the Yarra.

Also, switching from Surround to Stereo is mental, you can save profiles for each but it does not respect the setting so if I ever need to change it have to open the app on my phone or plug it in to the laptop instead of press a button on the remote.

I have no doubt the unit can do as advertised regarding the beamforming and surround effect and when it works it is great but it currently is a little rough around the edges for usability and reliability.

Will post back further updates and results after any new firmwares and also happy to do any testing if anyone has requests or has solved the HDMI dropout issue :)
Hi, thanks for sharing your experiences!

I have also been doing lots of testing on Xbox. I have a Win 10 and Dolby aAtmos for headphones but not HDR. I have a shield too but haven’t tried it yet. I experience dropouts on HDMI too but also on optical (at least from the Xbox) albeit to a much lesser degree. I have tried sending Atmos for headphones to the Yarra but found it to require the Yarra’s surround mode to be engaged for correct positional cues but then that would ruin the audio quality. Try the two forest demos on the Dolby Access app and compare it to actual headphones, I’d be be surprised if you didn’t notice a significant drop in fidelity by engaging the Yarra’s surround setting in that particular context. I found it sent the frequency level all over the place (in practical effect rather than on the Software apps equalizer function, which was at default neutral / flat) and made mids and highs sound very thin, sibilant and unnaturally boosted.

PCM Surround

As for Multichannel linear PCM, my experiences with getting some sound aren’t entirely different from yours but I hadn’t previously mentioned them as I had discounted them. I did get a “center” channel and voices on the center channel sometimes but the volume was very weak in comparison to other effects. Sometimes, I was able to get some semblance of sides and rears through linear PCM output on Xbox BUT, this was not always recreatable even on the exact same content used in the exact same context, and, when it did happen, channels were missing (positional gaps when rotating the in-game camera around my character in various games). Most crucially however, and the reason I discounted it until now, was that in terms of depth, those LPCM ‘surround’ channels which were providing cues sounded much more like basic 2.0 stereo up-mixed into pseudo-surround rather than properly processed ‘true’ surround obtained when the Yarra decodes and outputs DD5.1 Surround content.

Reliability of Blue LED Dolby Digital Processing indicator

I also wouldn’t put absolute faith in the blue LED Dolby indicator. I have had that come on more than once when switching between LCPM output and add bitstream and I have also had it stay off when Dolby Digital 5.1 was clearly being fed to the system. . . Meaning that either the source device (Xbox etc.) was glitching and getting confused about what I was telling it to send to the Yarra or else the (software powering the) Yarra was getting confused about what format it was actually receiving and was misrepresenting that in the on / off status of the blue light and/or not changing its mode of operation accordingly. It didn’t happen often but when doing A/B tests between different settings and sources, it occurred with enough frequency to notice and to require I pay even more attention to the settings and modes engaged in testing on all devices in the chain!


Optical

I haven’t found any significant difference between optical quality and HDMI quality other than that optical is less prone to glitching artefacts and dropouts which only seem to occur when Dolby Digital processing is engaged.

Dolby Dropouts

As above, only happens to me when Dolby processing mode is engaged (surround or stereo). Interestingly, it can still output linear PCM 2.0 when this happens (if I say change to a different input or change the source output format to feed it non-Dolby / PCM). Sometimes, changing the settings on the app or with the remote and then back again, will restore the sound in DD5.1 mode. Sometimes, disconnecting the source cable (optical etc. and reconnecting) will work. But following the last firmware update, I now sometimes even have to cold reboot the system before I can restore DD processing.

I will do some more tests in light of your findings though to see if there was anything I missed.
 
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Jul 29, 2019 at 3:29 PM Post #192 of 291
Hi all,

First and long post!!

UK backer received mine cpl of weeks ago but was a bit I'll to do much testing initially.

Subwoofer is pretty poor, I was also getting the issues with it triggering to on but the first firmware update mostly fixed it and then I swapped it for a powered Yamaha I had in the loft and then to a slightly smaller Harman Kardon with a better lead and it kicks in straight away and makes a much fuller sound so if you have a spare sub give it a blast!!

Mainly using far but also using near on headshape 7 which seems to like my block shaped head haha and when working well you can get good positional audio from binaural recording or a binauralised output from the Xbox but it is getting it to work fine...

I am on latest firmware and can agree with lpcm statement above in regards to no center channel being mixed in to the sound, can hear surround effects but no center channel/voices.

This has been using my Nvidia Shield, the only counter to that would be Amazon Prime which is 5.1 and does get all channels mixed and in surround without the blue light confirming DD on the unit.

Any other output on the Shield (mainly Kodi/Emby) to 7.1 channels so I could send decoded TrueHD etc is missing channels which is super annoying after the updates and the fact it is 2019 so regular DD 5.1 is so limited in bitrate etc we really need LPCM to be working. I am pretty sure I was still at school in 1996 when I got my first DD supporting Amp and speakers so supporting something a bit newer is really needed!!

This brings to my next and main issue and that is audio dropouts on HDMI, after Atmos was advertised then confirmed as not supported natively enquired about using the Atmos output to HDMI headset on Xbox/Win10 on Kickstarter and was advised that would be a good way to still get 3d audio out of the device (Think it was Dr AIX that replied at the time) but it just cuts out all of the time, when it is working it is awesome but cannot handle the dropouts. These don't just happen on the Xbox but any HDMI device I use, a cold reset normally resolves for a random period of time except the Xbox which goes dropout crazy!!

This does not happen on Toslink but the sound quality is degraded which I guess is that it drops to a 16bit @ 44khz DD 2.0 stream.

Does anyone have a HDMI 2.0 Win10 pc that can test HDR playback with Atmos for headsets enabled?

Wondering if that part of it is Xbox related as the cold reset fixes on other devices but not when in game on the Xbox. Looking to get a little NUC or something if it can do HDR and Atmos with the Yarra.

Also, switching from Surround to Stereo is mental, you can save profiles for each but it does not respect the setting so if I ever need to change it have to open the app on my phone or plug it in to the laptop instead of press a button on the remote.

I have no doubt the unit can do as advertised regarding the beamforming and surround effect and when it works it is great but it currently is a little rough around the edges for usability and reliability.

Will post back further updates and results after any new firmwares and also happy to do any testing if anyone has requests or has solved the HDMI dropout issue :)
Hi one test I tried today was an android phone supporting Dolby Atmos for headphones plugged into the aux jack and a Dolby Atmos demo
Some of the YouTube Dolby Atmos demos using near field setting and sub active produced interesting results
Sitting about 4 ft away it was fairly convincing with close to I can only call it a swirling sound field moving around in a spherical path way outside of the physical size of the Yarra
I think the Yarra can using psycho accoustics emulate Dolby Atmos with a few restrictions
It's early days hoping once the fw updates arrive it will be even better
What I am not convinced about is that the Yarra makes a good hdmi TV soundbar with its current sub as it isn't even close to my existing 5.1 sound system
 
Jul 29, 2019 at 6:19 PM Post #193 of 291
The products shipped to the U.S. were due to arrive in California on July 22nd. Does anyone have any verification as to whether or not that actually took place? Also, have any backers in the U.S. received track information? Thanks.
 
Jul 29, 2019 at 9:16 PM Post #194 of 291
This was posted on the Kickstarter page 3 days ago:

"In case anyone in the US is wondering where there units are, this is the reply I got:
"Hello,
Tracking numbers for US delivery have not been released. We will update everyone when the units arrive at Fedex port of Los Angeles.
Thank you!""
 
Jul 29, 2019 at 9:20 PM Post #195 of 291
I just posted this comment on the Kickstarter link for the YARRA 3DX

"
Great News for US backers.

I am in the Los Angeles area and I got a text from Fedex that my YARRA will arrive tomorrow - Tuesday. I am registered with Fedex to receive texts as shipping status changes. YARRA tracking had been listed as PENDING since 6/12/2019.

I have not yet received any tracking information directly from Comhear

"
 

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