Is the sound quality of the Bluetooth headphones not good? Part 4
What is low quality Bluetooth codec?
SBC (Sub Band Codec) is a codec that is said to have low sound quality, unlike high sound quality codecs like AAC, aptX, aptX HD, and LDAC.
In general, according to a wireless connection (radio) apparently towards the low sound quality Bluetooth connection with a wired connection connecting the AUX connection cable or the like Bluetooth, also flat sound and lengthening treble lost the stereoscopic realism Sound quality is said to be often suppressed, which is largely due to this SBC.
SBC, which is a codec specified as standard support in A2DP for music streaming, has become a specification that considerably sacrifices sound quality due to reasons such as reducing the hardware load of the computer under the premise at the time. specification …
Although the sound quality is low, on the contrary, there are few restrictions on the device side and it has been adopted in various devices, so it can be said that it was the engine that drove the widespread use of Bluetooth.
Bluetooth A2DP codec list
Using the bitrate as an index that determines the sound quality, if you rearrange the Bluetooth A2DP codecs in a list,
[Reference] FM radio: about 96 kbps
SBC: Since it is a standard A2DP codec, it can be used with all devices that support Bluetooth A2DP. Practically 64 to about 200 kbps.
AAC – Originally the format adopted by the iTunes Store. Widely used in Apple Bluetooth devices such as iPhone and iPod. Effectively up to 320 kbps.
aptX – Currently developed by CSR Limited, which was acquired by Qualcomm. Really up to 384 kbps.
aptX HD – Like aptX, developed by CSR Limited. Actually up to 576 kbps higher than aptX.
LDAC: developed by Sony. It is mainly used to connect high quality sound sources, such as high resolution. Really up to 990 kbps.
[Reference] Media that records compressed sound sources such as mp3 / AAC: Nearly 64 to 320 kbps
[Reference] CD (-DA): 1,411 kbps
Will be. The higher the number, the greater the amount of data per second, so the sound quality is considered to be higher. The Bluetooth connection via SBC is approximately 200 kbps even under the best communication conditions. If the communication conditions are bad, the amount of data transfer will be reduced to the equivalent of 64 kbps and the sound quality will be lower than that of FM radio.
For example, generally well compressed sound source data, such as mp3 or AAC, used is a data amount of about 256 kbps, when selecting the SBC as the codec, the Bluetooth connection, the part of the Bluetooth connection due to the low SBC quality, it becomes a bottleneck.
SBC has already finished its role in popularizing Bluetooth to some extent. In the future, considering that the maximum bit rate supported by general compressed sound sources like mp3 and AAC is 320 kbps, AAC, aptX, aptX HD and LDAC, which are high quality sound codecs with a standard of 320 kbps or higher. , it will be possible. I think you should use it as much as possible to make a Bluetooth connection.
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4 points to consider when using a high quality Bluetooth sound codec (AAC, aptX, LDAC)
Next, I would like to write about the precautions when using high quality sound codecs when connecting to Bluetooth A2DP: AAC, aptX, aptX HD and LDAC.
Generally speaking, there are four points to consider when connecting a high-quality Bluetooth A2DP sound codec.
Both connected devices must support the same high-quality codec
Be careful of wireless connection environment other than Bluetooth, such as WiFi and radio wave interference
AAC codec support such as Bluetooth A2DP is required instead of AAC file support
Reconfirm the A2DP codec selection settings for the Bluetooth connection
