Many users are currently complaining about the sound quality of Spotify. A new open-source codec called Opus is available and it may improve the sound quality on the same bitrate to improve extreme quality for premium users. Also, when Spotify will already use the codec, they can reduce the bitrate of the normal quality without reducing the sound quality. It is great for reducing bandwidth use and making songs faster to load. It will also make the users who use old versions be discouraged to use the old app. A comparison of Opus to other codecs is in this link https://www.opus-codec.org/comparison/ . Examples are here http://opus-codec.org/examples/ .
Hey folks, currently we have no plans to switch to Opus. This idea will remain open for kudos even with the 'Not Right Now' status and we'll continue to bring your feedback to the teams here at Spotify, thanks!