If entirely new things is what you're looking for, you're not really looking for a recommendation algorithm [1]. What these algorithms try to achieve is finding unknown songs that are in the same genre to what people already like.
[1] Technically "random song not in listen history" would work out, if you'd really like to call that a recommendation algorithm.
[1] Technically "random song not in listen history" would work out, if you'd really like to call that a recommendation algorithm.