So the JBL Go 4 is a very impressive micro speaker that does a very impressive job of keeping up with the JBL Clip 5. The Go 4 gets impressively loud for it size, it has a decent battery life for its size and it has aura cast. The Go 4 is a solid compact option… and its so impressive is does a great job of keeping up with both the Sony XB100 and the Bose Soundlink micro.