I bought both the XB20 and XB30. They were my first wireless speaker purchase and I was expecting that the XB20 would be more then enough for me. And don't get me wrong, it sounded really good. The sound quality is there. But after then hearing the XB30, I couldn't go back to the XB20. The bass is definitely better on the XB30; there isn't really very much bass with the XB20. Both speakers sounded great and clear at high volumes, but the bass sets the XB30 apart; and it does get louder. I guess it depends on the kind of music you listen to. If bass is not a priority, then go ahead and the get the XB20, but if your options are two XB20s or one XB30, I'd go with the XB30.