Currently we know of no way to bass boost the JBL Go 2 using just its controls. But if this were possible, it would make the speaker boom more. By this, we mean that boosting the bass would add a stronger bass characteristic to the playing content. Thus if JBL ever added this, it could work something like the following…
How to Bass Boost JBL Go 2: Step by Step
First of all, by default, the Go 3 would have its bass boost mode turned ON. Indeed, this operation is like many of the other speakers in the JBL line. This mode would add more treble and notably more bass. This would be like switching on the Loudness control on vintage stereo systems.

How to Bass Boost JBL Go 2: Turn it Off – Proposal
For example, find the Bluetooth and Volume Down buttons on the top of the speaker. Find these in the picture above.
Then, you could turn bass boost mode OFF by pressing these buttons. Hold them in for about ten seconds. Finally release when l the pilot lamp on the front blinks a few times.

Finally, to turn bass boost mode back on, you would press the Volume Down and Bluetooth buttons as before. Then, keep holding until the light again flashes a few times. You would release the buttons after that. Finally bass boost mode would come on once more.