aptX Adaptive / aptX Lossless USB Transmitters

[mcnaugha]

This is an interesting thread.

I'd like to upgrade the Bluetooth audio output on my Microsoft Surface Pro 6 beyond Aptx. The use case is as follows:

Headphones/recievers:
1 - Sennheiser Momentum 4 Wireless (SBC, AAC, Aptx, Aptx HD, Aptx Adaptive)
2 - Hifiman Deva Pro with R2R Bluemini (SBC, AAC, Aptx, Aptx HD, LDAC)
3 - Qudelix 5k (Everything)

Transmitters:
Sony Xperia 5iii (SBC, AAC, Aptx, Aptx HD, Aptx Adaptive, LDAC, also includes Snapdragon sound) - don't need the dongle here.
Microsoft Surface Pro 6 (SBC, AAC, Aptx, LDAC*)

*I tried the Beta Alternative A2DP drivers for Windows from Bluetoothgoodies.com and they do work up to 660 kbps with the LDAC devices. At 900 kbps there's stuttering and the music is slow with any sample frequency on both devices 2 and 3.

The Nura or Creative USB dongles look like options as they maintain portability while achieving Aptx HD/Adaptive depending on the receiver. Based on listening tests I can't tell the difference between LDAC, Aptx HD and Adaptive and in fact LDAC is substantially less stable. So, achieving a minimum of Aptx HD is fine.

On the Sony phone I can swap between codecs manually under developer settings. With the Quedelix and M4Ws I can use the respective app to check the codec being used (no such option on the Hifiman R2R but Bluetooth Tweaker shows what codecs are compatible.)

Based on my reading of the backward compatibility of Aptx Adaptive with HD a transmitter with Adaptive should be able to provide HD to a receiver that has HD but no Adaptive. This would be the case for the Deva Pro R2R, which I would need to make sure received HD rather than Aptx Classic. Is this correct?

Thanks

MG

I’m asking Nura support to clarify the discrepancies between the main product pages, the product packaging and help documentation. The main product page for the transmitter does not list aptX HD as a stand-alone codec. However the packaging has the aptX HD logo.

I just performed a check and based on an assumption that the transmitter does not have the aptX HD codec, my aptX HD receiver successfully connected. It speaks out the codec that’s been selected and it did indeed say aptX HD. This would happen because aptX Adaptive transmitters can support aptX HD receivers. It would also happen if the aptX HD codec has been additionally licensed on the transmitter. It does not come by default with the QCC3056. Regardless of the truth here, it should serve your purposes.

The alternative Chinese transmitters would also serve your purposes.

 

[helmutcheese]

I had no issue at any bitrate with the Beta Alternative A2DP Driver on the new crappy SoundPeats Mini Pro HS or my higher end FiiO Neckband (same on the FiiO BTA30 PRO) and this was with an Intel AX210 (WIFI6E/BT 5.3).

Again, there is NO backwards compatibility between aptX Adaptive and aptX HD, you end up listening to aptX (either direction it is the same so does not matter which device had it).

 

[master grunthos]

I’m asking Nura support to clarify the discrepancies between the main product pages, the product packaging and help documentation. The main product page for the transmitter does not list aptX HD as a stand-alone codec. However the packaging has the aptX HD logo.

I just performed a check and based on an assumption that the transmitter does not have the aptX HD codec, my aptX HD receiver successfully connected. It speaks out the codec that’s been selected and it did indeed say aptX HD. This would happen because aptX Adaptive transmitters can support aptX HD receivers. It would also happen if the aptX HD codec has been additionally licensed on the transmitter. It does not come by default with the QCC3056. Regardless of the truth here, it should serve your purposes.

The alternative Chinese transmitters would also serve your purposes.

Thanks for the rapid reply. It'd be interesting to see what Nura say before I decide which one to go for.

 

[master grunthos]

I had no issue at any bitrate with the Beta Alternative A2DP Driver on the new crappy SoundPeats Mini Pro HS or my higher end FiiO Neckband (same on the FiiO BTA30 PRO) and this was with an Intel AX210 (WIFI6E/BT 5.3).

Again, there is NO backwards compatibility between aptX Adaptive and aptX HD, you end up listening to aptX (either direction it is the same so does not matter which device had it).

It's interesting that when I force Aptx HD on the Sennheiser M4W from the developer settings of Android the Sennheiser App actual says "no codec" but the phone believes it's using Aptx HD. In fact, if i select Aptx, it bumps it up to HD automatically (same for the Deva Pro R2R dongle). Similarly, Bluetooth Tweaker shows Aptx HD listed as the first codec for the M4W, with Adaptive at 5. This is vs the Sennheiser documentation, which is silent on the matter of HD.

The beta drivers on the Surface pro may not be working correctly with my specific PC hardware. It's plausible that the BT transmitter in the Surface is pretty weak like the Wifi is. Even with 660 kbps there's times it's a bit choppy and this very rarely happens when using the Sony phone.

 

[helmutcheese]

QUALCOMM either worded it poorly or were BS'ing at prelaunch, I had to contact Moto/Lenovo and got told the bad news for my older flagship phone.

Now with our Dongles we can disable certain Codecs in the App to test it in the opposite direction (as some claimed that is what QUALCOMM meant) and again it will fall back to aptX and if you only leave aptX HD enabled it falls back to SBC on any aptX Adaptive buds I have tried including Sennheiser MT3.

I have just accepted 99% of my music is CD Rips so 16/44.1 so no Hi-Res Codec needed or else it will be up-sampled in the player if it supports this).

 

[mcnaugha]

I had no issue at any bitrate with the Beta Alternative A2DP Driver on the new crappy SoundPeats Mini Pro HS or my higher end FiiO Neckband (same on the FiiO BTA30 PRO) and this was with an Intel AX210 (WIFI6E/BT 5.3).

Again, there is NO backwards compatibility between aptX Adaptive and aptX HD, you end up listening to aptX (either direction it is the same so does not matter which device had it).

The Nura transmitter appears to be the first dongle of its kind which does not actually include the standalone aptX HD codec. All of the Chinese ones have aptX HD as an additional standalone codec, which must have been enabled by negotiation with Qualcomm.

So, this is the first time I’ve been able to prove that aptX Adaptive does have the promised backwards compatibility with aptX HD-only/no higher receiving devices. It has always been this one-way backwards compatibility.

This cannot be proven or disproven without a transmitter which does not support/include the aptX HD codec.

 

[helmutcheese]

The Creative new Dongle does not have LL or HD unlike its predecessor.

I have a FiiO Neckband which is LDAC at its highest Codec but aptX HD at its highest QUALCOMM Codec so LDAC would not matter/count in this testing, and it falls back to aptX if I try to connect via aptX Adaptive to our Dongles or SBC if I disable all Codecs (leaving only aptX HD) in the FiiO App and try to connect to the Dongle.

I knew Nura had an App but to not add the Dongle to it IMO was short-sightedness esp as a higher end product.

 

[mcnaugha]

The Creative new Dongle does not have LL or HD unlike its predecessor.

I have a FiiO Neckband which is LDAC at its highest Codec but aptX HD at its highest QUALCOMM Codec so LDAC would not matter/count in this testing, and it falls back to aptX if I try to connect via aptX Adaptive to our Dongles or SBC if I disable all Codecs (leaving only aptX HD) in the FiiO App and try to connect to the Dongle.

When the devices are doing their handshake and asking what codecs are available in each, they will still be told that the Chinese dongles are capable of aptX HD even though it’s also been blocked. The blocking can’t be taking it out of the initial handshake.

The aptX HD receivers then attempt only aptX HD with a fallback of aptX. They ask for aptX HD then the dongle is saying “nope” because of the setting we can do. This causes the fallback to aptX Classic. The only time aptX Adaptive can step in and act as aptX HD is when aptX HD itself isn’t there at all.


I forgot about the BT-W4 maybe because I never owned it. It should be able to demonstrate the same outcome as I’m seeing with the Nura.

 

[helmutcheese]

You would really need some kind of GUI to be 100% sure but I wish it did work as I was disappointed when my Soundpeats aptX HD Neckband at that time fell back to aptX when I was listening to Amazon HD (24/48), till I got the FiiO Neckband then I could use LDAC 24/96.

I would buy the Creative tomorrow if it was not for the lack of 24/96 (which Chipset does support) and the missing classic aptX LL/HD Codecs even though they are not needed as PC+FiiO BTA30 PRO does that between them.

The App is nice and updates no doubt for FW/App, thye also change the button press to switch devices not codecs (be nice to have both functions) you sue the app for the later now AFAIK.

 

[master grunthos]

So, one strategy might be to force Aptx HD for the set of headphones I have by getting a dongle (Creative BT-W3 for example) that only supports up to Aptx HD. For the use case I have, when all headphones appear to have HD that would end up the codec being used.

While Sennheiser don't mention Aptx HD in the manual for the M4W the reviews do and Aptx list it: https://www.aptx.com/products/sennheiser-momentum-4

that said they also have list HD on the Nura page: https://www.aptx.com/products/nura-bluetooth-5-3-audio-transmitter

I also spotted that they are explicit regarding the backward compatibility with both Aptx and Aptx HD on this page: https://www.aptx.com/aptx-adaptive which if not true is slightly troubling

 

[helmutcheese]

The B&W P14 Neckband (one of the first aptX Adaptive devices) did do aptX HD in this situation as they added the standalone HD Codec and again this was confirmed first by Moto/Lenovo and again later when I contacted B&W.

aptX Adaptive is basically a hybrid of LL+HD along with other new features, I posted the screens in this thread showing it has a LL type mode and a HD type Mode you can select.

IMO the claim made me think/hope it did fall back to aptX HD but now it does not going by what I have been told by 2 official sources and the little testing I can do which is now in both direction due to our Dongles.

In principle it matters to me but in reality, less so now as we have newer devices.

 

[master grunthos]

The inconsistency of information on the manufacturer's websites is quite poor. Qualcomm list the sennheiser btd600 dongle as aptx and aptx adaptive but sennheiser have HD as well on their information.

 

[Blacklands]

The inconsistency of information on the manufacturer's websites is quite poor. Qualcomm list the sennheiser btd600 dongle as aptx and aptx adaptive but sennheiser have HD as well on their information.

I just did a quick test for that, with my Qudelix 5k. I disabled Adaptive on it (so that it only lists regular aptX and HD as available to the transmitting device), and then connected to the BTD 600. The BTD 600 selected (regular) aptX as the codec. So it doesn't seem like the BTD 600 can do HD.

EDIT: I also have a Bluetooth speaker (the Soundcore Motion+) available, which can only do regular aptX and HD, but not Adaptive. I wanted to test with that too, but for some reason I can't get it to connect to the BTD 600 at all. Maybe I'll try to get that fixed later.

 

[schlomistan]

Hey, I got my Moondrop Sparks working with KB9P. Thanks to everyone who helped.

Currently I'm trying to use the "KB9_KB9P_Assistant_Eng_ver_test" but all it says is "No device found" no matter what I try.
There was also a sudden drop in sound quality at one point but I read in their guide that it could be fixed by disabling mic so I did that. Hopefully it doesn't come back.

How do I use the translated Bluetooth Assistant?

 

[mcnaugha]

Hey, I got my Moondrop Sparks working with KB9P. Thanks to everyone who helped.

Currently I'm trying to use the "KB9_KB9P_Assistant_Eng_ver_test" but all it says is "No device found" no matter what I try.
There was also a sudden drop in sound quality at one point but I read in their guide that it could be fixed by disabling mic so I did that. Hopefully it doesn't come back.

How do I use the translated Bluetooth Assistant?

English version assistant:
Link: https://pan.baidu.com/s/1XX63vPUcEHV68Fgp9Xp4VQ
extraction code: qiyi

KB9P Firmware update:
Link: https://pan.baidu.com/s/1jfysDBxGd3xY48GTQ-5JPg
extraction code: qiyi

must update the firmware to use latest assistant.