Netflix increases audio bitrates and adjusts quality based on bandwidth

Netflix has made changes to audio playback. The streaming service increases bitrates, up to a maximum of 768Kbit/s for Dolby Atmos. For devices that support this, Netflix adjusts the audio quality to the available bandwidth.

Netflix has set out details about the changes in a blog post. In it, the service writes that the improved audio quality is not lossless, but ‘transparent’. Netflix claims that there is no difference with the source material at the bitrates that the service uses. For Dolby Digital this is a maximum of 640Kbit/s and for Dolby Atmos streams it is up to 768Kbit/s.

Netflix also adjusts the bitrate to the available bandwidth for devices that support this. The service has been doing that for video for some time now. If the connection is good, a high bitrate is used and if the bandwidth is limited, the bitrate goes down. According to Netflix, the switches are not audible.

For videos with 5.1 audio, an audio stream of a minimum of 192Kbit/s to a maximum of 640Kbit/s is offered. According to Netflix, the lowest quality is therefore also ‘good’. The service notes that the bit rates may still change in the future, for example due to new techniques to encode the sound.

Not all hardware supports adjusting the audio quality to the available bandwidth, but Netflix states that most TVs can handle it and says it is now using the technology. The service has been testing for a year with different TVs.