So this is the JBL Xtreme 4, and there are some significant upgrades here from both the JBL Xtreme 3 and Xtreme 2… upgrades that are very similar to both the JBL Partybox 320 and Partybox 120. Nonetheless, if you’re think about picking up the JBL Xtreme 4 or upgrading from the JBL Xrteme 3 or even the JBL Xtreme 2… lets see what the JBL Xtreme 4 is all about.