JBL Xtreme 3 is a good alternative to the heavy Boombox 2, and only half as expensive.
JBL Xtreme 3 review: Boshing out the bass
JBL Xtreme 3 review: Extremely loud, not so portable - SoundGuys
Review: JBL Xtreme 3
JBL Xtreme 3 review: Boshing out the bass
JBL Xtreme 3 in review: The portable bass monster with style
Waterproof Portable Bluetooth Speaker - Blue
JBL Lifestyle Xtreme 3 Waterproof Portable Bluetooth Speaker - Blue
Xtreme3 : r/JBL
Slashes 26% Off JBL Xtreme 3–Save $100 on This Cool Bluetooth Party Speaker!
JBL Xtreme 3 (Black) Waterproof portable Bluetooth® speaker at Crutchfield