High-quality audio is designed to provide audio that more closely matches with what creators hear in the studio, resulting in a "richer, more intense experience."
Netflix's audio bitrate now goes up to 640 kb/s on devices supporting 5.1 surround sound and 768 kb/s for devices that support Dolby Atmos. For the improved Dolby Atmos sound, a Netflix Premium subscription is required.
Most TV devices that support 5.1 or Dolby Atmos are capable of receiving better sound. Depending on your device and bandwidth capabilities, the bitrate you receive may vary:For those with bandwidth or device limitations, the high-quality audio feature is adaptive, so it will provide the best possible audio to match your device or connection's capabilities.
5.1: From 192 kbps (good) up to 640 kbps (great/perceptually transparent)
Dolby Atmos: From 448 kbps up to 768 kbps (Dolby Atmos is available for members subscribed to the Premium plan)
Netflix says its new bitrates will "evolve over time" as its encoding techniques get more efficient.