I have own 26 speakers. 24 since 2002. The best or the most musical is my current pair, of course, right? Anyway they are the KEF Reference 5 Meta's. I love them to bits, they really draw me in. They also happen to be the most expensive speaker I have owned. But in fairness to the other models and brands I have owned I wasn't as good at system building/matching in the past so I'm sure that because I am more experienced now it has benefited in how I am able to really light the KEFs up.
As far as previous speakers that have had in the past that I found musical, there are two that stick out. One is a pair of WLMs. I can't remember the model, but those were easy on the ears and a lot of fun. Another pair I have had that are not to expensive are the Dynaudio Evoke 50s.