Bluetooth handsfree better quality

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Is it somehow posibble to get better audio quality sound when Bluetooth headphones are on hands-free mode? Because when it is only audio, sound qaulity is good (16-bit 44 kHz), but when I need to talk through the microphone, audio quality is changed to poor (16-bit 8 kHz), like old radio. Or I do not hear something through headpones. I have Creative Sound Blaster Jam.

Simple, have set Bluetooth Audio Renderer (Bluetooth stereo audio), for playing, with Bluetooth Audio Input Device (Bluetooth Hands-free audio), for recording?

OrdinaryNick

Posted 2016-07-16T10:19:59.550

Reputation: 83

Which bluetooth chipset are you using? Broadcom? CSR? other? and what software you are using to make phone calls? – Eden – 2016-12-02T13:38:25.873

Answers

8

Short:

No

Long:

There are so called Profiles in Bluetooth, and only one can be active at a time.

A2DP supports one-way HQ audio.

HSP/HFP support two-way audio, but only with very poor quality (HFP 1.6 added mSBC, which is a 16kHz mono codec, before, it was even worse).

(ref http://www.tomshardware.co.uk/answers/id-3399361/bluetooth-headsets-high-quality-audio-microphone-simultaneously.html)

(I added the same answer to both Is it possible to use a bluetooth headset mic while having High quality sound and Bluetooth handsfree better quality because they are found using google.)

Lukas Rieger

Posted 2016-07-16T10:19:59.550

Reputation: 550

1The tomshardware post says there's not enough bandwidth, which is not correct. Bluetooth Classic supports bitrates up to 24 Mbps, which is more than sufficient to carry two stereo streams with a low-latency, CD-quality codec like Opus at around 192 Kbps each. The total bandwidth use would be under 400 Kbps, or 1.6% of the theoretical throughput of Bluetooth Classic. This would allow reliable transmission even with very low signal strength. – allquixotic – 2018-03-09T02:22:29.093

2

It is even more complicated: not only HFP (Hands Free Profile) 1.6 (2011), but even HFP 1.7 (2018) consider mSBC codec (the prerequisite for feature called Wide Band Speech - basically sample rate: 16 kHz / 16bit) optional in both

  • HF (Hands Free - the headphones)
  • AG (Audio Gateway - the computer, cellphone).

See Table 3.1, page 19.

Also:

Since it is only the AG that knows if wide band speech should be used, it should always be the AG that establishes the Synchronous Connection with the required codec.

2.3 d, page 16.

So it is not uncommon that the same HF working perfectly with mSBC under Android AG (e.g. Jabra Elite 65t) fails miserably under Windows 10 with mSBC and all you can do is buying Jabra Evolve 65t for 3x higher price to get the expected result. Or replace Windows with Android...

Oh, you thought of even better quality than mSBC/WBS? Unfortunately, no chance unless somebody comes with "A2DP microphone" :-(

Alice Vixie

Posted 2016-07-16T10:19:59.550

Reputation: 121