Spotify Premium gives you access to high-quality music streaming. While on default (especially if you are making use of a free plan), Spotify streams at 96kbps on your mobile phones and 160kbps on your computer. At these sort of bitrates, you will be able to hear a small but perceptible deterioration in audio quality when compared to an audio CD.
If you’re interested, take a clue from NPR. It provides you with one song in three distinct formats; a 128kbps MP3, a 320kbps MP3, and an uncompressed WAV. It would be then up to you to select the highest quality from the available options. Avoiding the lowest quality presents no difficulty, but being able to select between 320kbps and lose less with consistency breeds a problem.
If you’re interested in getting your songs at 320kbps or higher, this is how you do it:
On Your Mobile Device
Open Spotify, click on Library tab, click settings on the top right. On iOS, click on Music quality, on Android keep scrolling down until you can find it.
The three different audio qualities available on Spotify include; Normal (96kbps), High (160kbps), and Extreme (320kbps). An Automatic option is available to actively regulate the bitrate based on your network quality and the network you make use of.
One audio quality can be used for streaming and another for tracks you actually download. Note, the higher the bitrate the more the amount of data that will be required and the more capacity the tracks will absorb when downloaded.
I prefer High format for streaming and Extreme for downloads because I think it creates a balance between having high quality music and streaming over cellular data without difficulties.
On the Desktop
Open Spotify, click on the arrow facing downwards on the top right corner close to your username, and then click on settings.
While under Music Quality, click on High Quality Streaming.
This allows for streaming at 320kbps.