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Wireless audio is good. But the one freaking thing I cannot understand is why after almost 20 years of wireless audio in computers, the microphone quality is s

Wireless audio is good. But the one freaking thing I cannot understand is why after almost 20 years of wireless audio in computers, the microphone quality is still atrocious. Anyway, I know the next version of Bluetooth will fix it.

izacus 4y ago
Because the bandwidth, bitrate and audio codec for HFP profile hasn't been upgraded in a decade. AptX and co. are only used in stereo profile with no mic support. As soon as you request bidirectional audio it downgrades to horrible old codecs.
ajsnigrutin 4y ago
> Anyway, I know the next version of Bluetooth will fix it. I knew that back in the time of bluetooth 2.0. Sadly it didn't... especially not the high quality stereo audio + microphone at the same time.
- mort96 4y ago
  Was better bidirectional audio advertised as a feature of Bluetooth 2.0?
  - ajsnigrutin 4y ago
    No, but "the next version will surely have that". And versions are comng up to 5.4 now.
j45 4y ago
Always the next version of Bluetooth. It just needs more research and committees and not using it in the wild.
- AshamedCaptain 4y ago
  There has been no new features or changes in bluetooth audio for two decades. The new LE audio is the first new version ever since a2dp was introduced.
  - j45 4y ago
    Oh I’m aware. It’s 30 year arc is a notable example of academic design by committee. Also have abused way too many people through way too many versions of Bluetooth.
mkopec 4y ago
aptX LL actually supports bidirectional audio. There's also the Faststream codec that does SBC in both directions. For some reason almost no one implements any of these and we're left with atrocious HSP/HFP profiles.
- abdullahkhalids 4y ago
  This comment [1] claims > LL was unfortunately discontinued by Qualcomm. AptX adaptive is all that remains and it unfortunately has more latency than LL but probably less clicking and microsecond dropouts which I assume is why Qualcomm moved away from LL along with LL requiring dedicated antenna hardware [1] https://old.reddit.com/r/Android/comments/11t16lk/qualcomm_has_open_sourced_its_aptx_and_aptx_hd/jchcojc/ https://old.reddit.com/r/Android/comments/11t16lk/qualcomm_h...
rcme 4y ago
Here are two factors: Cellphone audio is transmitted at some ridiculously low bitrate (8k?). AirPods, and probably other Bluetooth headphones, reduce the audio output quality when the mic is on. This is to save on battery life.
- anotherhue 4y ago
  It's more of a latency thing, though modern codecs should be able to move past that restriction. Most HFP devices still drop into mid '90s mode for call audio.
  - rcme 4y ago
    Why does audio latency matter when the mic is active?
    - themitigating 4y ago
      If you are talking to someone it's bidirectional and high lag can make a conversation annyoing where you interupt people
      - rcme 4y ago
        That's surprising to me. It's very distracting to watch a video of someone talking that has even a slight audio sync issue. The noticeable delay when watching a video is surely greater than the delay required for people to start talking over each other.
        themitigating 4y ago
        Yes but visual cues help you know when the other person wants to talk. Body language
        bestham 4y ago
        Either you are participating in a audio or video call and your audio is bidirectional or you are watching a video with stereo sound. If the latter the video player should buffer the video and adjust the delay of showing it to match up with the delay of the audio sink. If not there is a problem in your device.
x-complexity 4y ago
> But the one freaking thing I cannot understand is why after almost 20 years of wireless audio in computers, the microphone quality is still atrocious. Off the top of my head: 1) Wireless noise from other devices: WiFi signals from other devices can cause disruptions to Bluetooth signals. 2) Packet drops: Some packets from could be lost during the wireless transmission. 3) Software issues: Anything from outdated audio drivers, to dependency requirements, to the CPUs being hogged by something running in the background. 4) USB 3 interference: Apparently USB 3 introduce interference to the 2.4GHz range when it's being used. https://www.usb.org/sites/default/files/327216.pdf https://www.usb.org/sites/default/files/327216.pdf
- mort96 4y ago
  Those don't come into play here though. The problem with mic quality with Bluetooth is that we're still using the old headset profile for bidirectional audio. That means bidirectional Bluetooth audio maxes out at a sample rate of 16kHz and bitrate of 64kbit/s, with an ancient compression codec at that. I don't understand why nobody has fixed that. Even Apple, known to extend the Bluetooth spec to improve UX, seems to use the HSP for bidirectional audio between a Mac or iPhone and AirPods. I don't get it. Even if you kept the 64kbit/s bandwidth but switched to AAC you'd get a significant audio quality improvement since you could at least represent sound over 8kHz.
- hulitu 4y ago
  > 2) Packet drops: Some packets from could be lost during the wireless transmission. A very long time ago, they used buffers.
t344344 4y ago
Most likely you are using old GSM codec limited to 14kbps.

izacus 4y ago

Because the bandwidth, bitrate and audio codec for HFP profile hasn't been upgraded in a decade. AptX and co. are only used in stereo profile with no mic support. As soon as you request bidirectional audio it downgrades to horrible old codecs.

ajsnigrutin 4y ago

> Anyway, I know the next version of Bluetooth will fix it. I knew that back in the time of bluetooth 2.0. Sadly it didn't... especially not the high quality stereo audio + microphone at the same time.

mort96 4y ago
Was better bidirectional audio advertised as a feature of Bluetooth 2.0?
- ajsnigrutin 4y ago
  No, but "the next version will surely have that". And versions are comng up to 5.4 now.

j45 4y ago

Always the next version of Bluetooth. It just needs more research and committees and not using it in the wild.

AshamedCaptain 4y ago
There has been no new features or changes in bluetooth audio for two decades. The new LE audio is the first new version ever since a2dp was introduced.
- j45 4y ago
  Oh I’m aware. It’s 30 year arc is a notable example of academic design by committee. Also have abused way too many people through way too many versions of Bluetooth.

mkopec 4y ago

aptX LL actually supports bidirectional audio. There's also the Faststream codec that does SBC in both directions. For some reason almost no one implements any of these and we're left with atrocious HSP/HFP profiles.

abdullahkhalids 4y ago
This comment [1] claims > LL was unfortunately discontinued by Qualcomm. AptX adaptive is all that remains and it unfortunately has more latency than LL but probably less clicking and microsecond dropouts which I assume is why Qualcomm moved away from LL along with LL requiring dedicated antenna hardware [1] https://old.reddit.com/r/Android/comments/11t16lk/qualcomm_has_open_sourced_its_aptx_and_aptx_hd/jchcojc/ https://old.reddit.com/r/Android/comments/11t16lk/qualcomm_h...

rcme 4y ago

Here are two factors: Cellphone audio is transmitted at some ridiculously low bitrate (8k?). AirPods, and probably other Bluetooth headphones, reduce the audio output quality when the mic is on. This is to save on battery life.

anotherhue 4y ago
It's more of a latency thing, though modern codecs should be able to move past that restriction. Most HFP devices still drop into mid '90s mode for call audio.
- rcme 4y ago
  Why does audio latency matter when the mic is active?
  - themitigating 4y ago
    If you are talking to someone it's bidirectional and high lag can make a conversation annyoing where you interupt people
    - rcme 4y ago
      That's surprising to me. It's very distracting to watch a video of someone talking that has even a slight audio sync issue. The noticeable delay when watching a video is surely greater than the delay required for people to start talking over each other.
      - themitigating 4y ago
        Yes but visual cues help you know when the other person wants to talk. Body language
      - bestham 4y ago
        Either you are participating in a audio or video call and your audio is bidirectional or you are watching a video with stereo sound. If the latter the video player should buffer the video and adjust the delay of showing it to match up with the delay of the audio sink. If not there is a problem in your device.

x-complexity 4y ago

> But the one freaking thing I cannot understand is why after almost 20 years of wireless audio in computers, the microphone quality is still atrocious. Off the top of my head: 1) Wireless noise from other devices: WiFi signals from other devices can cause disruptions to Bluetooth signals. 2) Packet drops: Some packets from could be lost during the wireless transmission. 3) Software issues: Anything from outdated audio drivers, to dependency requirements, to the CPUs being hogged by something running in the background. 4) USB 3 interference: Apparently USB 3 introduce interference to the 2.4GHz range when it's being used. https://www.usb.org/sites/default/files/327216.pdf https://www.usb.org/sites/default/files/327216.pdf

mort96 4y ago
Those don't come into play here though. The problem with mic quality with Bluetooth is that we're still using the old headset profile for bidirectional audio. That means bidirectional Bluetooth audio maxes out at a sample rate of 16kHz and bitrate of 64kbit/s, with an ancient compression codec at that. I don't understand why nobody has fixed that. Even Apple, known to extend the Bluetooth spec to improve UX, seems to use the HSP for bidirectional audio between a Mac or iPhone and AirPods. I don't get it. Even if you kept the 64kbit/s bandwidth but switched to AAC you'd get a significant audio quality improvement since you could at least represent sound over 8kHz.
hulitu 4y ago
> 2) Packet drops: Some packets from could be lost during the wireless transmission. A very long time ago, they used buffers.

t344344 4y ago

Most likely you are using old GSM codec limited to 14kbps.