You can change how loud the bass is on the JBL Xtreme 3, by turning on and off its bass boost mode. When ON, extra bass mode makes the bass radiators on each end of the speaker vibrate a lot more. Furthermore, boosting the bass in this way adds a low rumble quality to the playing program, that travels pretty far from the speaker. So, for you boom lovers, this post shows how to bass boost this speaker, to get that extra kick.
How to Bass Boost JBL Xtreme 3: Turning it OFF
By default, this speaker has bass boost mode turned ON after a hard reset. This adds a bit of treble and lots of extra bass to the audio output as compared to when this mode is OFF.
You can turn this bass boost mode off by pressing and holding in the Volume Down (-) and Bluetooth buttons as pointed out by the green arrows in the last picture, for about ten seconds.
Hold in until all buttons on the top of the speaker light up white. Note these lamps glowing in the next picture. In fact, the light in just the same way during a speaker reset.
How to Bass Boost JBL Xtreme 3: Turning it ON
To enable bass boost once more, press and hold the Volume Down and Bluetooth buttons in until the Power and Connect buttons light white. Then release the buttons. When the buttons inside the circled oval above light white, bass boost has resumed once again.
Warning
The drivers really thump when you switch ON bass boost. So be cautious in how loudly you play this speaker with the bass boosted, to avoid damage to the speaker drivers. If the bass is crackling, tapping, or otherwise distorting, turn it down !