I don't have the link handy, but back in the day Thott from Afterlife complained that bard speed never increased from classic. Specifically, you can reach the fastest speed a bard can reach at lvl 50 with a Selo's drum. Once you have a Selo's drum, leveling from 50 to 60 will not increase speed, whereas if you have a drum with a smaller modifier, you will continue to see increases per level until you hit the equivalent of Selo's Drum at 50.
Nvm, I found the link
here. According to that link, if you're one of those lucky to have a Drums of the Beast, you can hit the bard speed cap at lvl 46.