When Han and company walked into Maz's cantina style bar, I was really hoping to see these guys from Episode IV playing:
But sadly, it was a different band - who were they?
Visual Dictionary (page 73) covers it in detail:
The band members are Taybin Ralorsa, Infrablue Zedbeddy Coggins, Ubert "Sticks" Quaril, and Sudswater Dillifay Glon.
No, I didn't make the names up. Here's proof:
Visual dictionary doesn't offer many (or any :) details on them, except that they don't seem to be a permanent house band.
The band you hoping to find was called Figrin D'an and the Modal Nodes, all 7 members were Bith.
In a sweet and delicious symmetry to those of us suffering from the overabundance of OCD, the band from Episode IV had 7 players, while the band from Episode VII had 4 players.
According to V.D.'s author, Pablo Hidalgo's twitter, the names are meant to be "blues" invoking and he's quite proud of them.