A user on Reddit was able to discover the first indication of the new HiFi streaming function in Spotify.
Did Spotify HiFi Streaming Start Soon?
Spotify has been planning to integrate a HiFi streaming option for a long time. The first Hints there was already in 2017. Now Spotify seems to push this topic further, because like a user on Reddit reported, he was able to take a screenshot of the new HiFi button shortly after starting the Spotify app.
By clicking on the button, the user could also learn more about the audio quality of Spotify HiFi. According to this, streaming in 16-bit 44.1 kHz is supported, in each case on compatible speakers or wired headphones. Official information from Spotify about the start of the new subscription variant and also about a price is currently not available.