OPUS or even AAC is OK at 128 kb/s already but player compatibility is low.
If you know you're going to be playing it on VLC, you can even fit a decently good-looking 90min H.265 movie on one. When H.266 becomes widely available, the movie can be in 1080p at about HDTV broadcast quality.
Not if you burn 128kbps mp3s! Slaps CD You can fit an entire discography in this bad boy.
OPUS or even AAC is OK at 128 kb/s already but player compatibility is low.
If you know you're going to be playing it on VLC, you can even fit a decently good-looking 90min H.265 movie on one. When H.266 becomes widely available, the movie can be in 1080p at about HDTV broadcast quality.