A picture of the control cavity would help us figure out what kind of guts you have in it ... this being said ....
It looks like you have a volume, pan, the stacked knobs, and what appears to be treble/bass boost/cut switches, and the Q-Switch. Now, if you have other electronics in it, you probably don't have the filter, and the other switches may do something else. If you have a Bart NTMB-918 pre, it would be volume, pan, and stacked bass/treble boost/cut controls. As to what the switches would do in that sitation, I just can't comment.
Nice bass, BTW.
Alan