Not rolls for eating mind, the audio variety.
Joking aside, yes the bass speakers under the seats I believe are with the premium option (can't remember what the name is in UK). You get some nice bass from them. Also there is a speaker in the center which helps with that surround sound bollocXs.
Premium sound is great, but (contrary to my initial observations when I first got it - mainly due to good power output and lack of distortion), not the best in the world.