I would not worry much about harming an Acme B2.
Andy quotes a frequency response of 41hz to 22khz, +/- 3 db. The fundamental of a low B string is 31 hz, less than half an octave below 41hz. And 22k is a towering high end for a 'bass cabinet'. Unless you're getting a lot of handling noise, the instrument is not generating anything lower than that playing-wise so you should be fine. The only other way to get lower than that would be to be tuned below low B or be using one of those octave-lower harmonizers . . . .
Edwin was right to point out that you could essentially dictate your signal frequency bandwidth with the SuperFilter, but signal strength (which ultimately drives the output of your amp to the Acmes) is best controlled by a limiter or compressor, of which a 160A is a fine mono dbx unit. This is where you can run into trouble: Amps driven into distortion can generate signals which can harm speakers. And here I mean, you're pushing barely enough amp for the job to the wall, and the power end is distorting, not a preamp distortion for effect. Usually though, very loud, clean outputs are not a problem within reason: Obviously, you wouldn't hook up a 2000watt Crest to a 5 speaker. But generally, more clean power than rated speaker-wise is not harmful in smaller doses.
Lots of guys here use Acmes, and they are in general tough little beasts routinely fed by 500 watt (or more) amps. The designer really did his homework and these are functionally way past your typical bass guitar cabinet.
So, if you're using a good preamp/power amp rig or a good head in the 300 to 600 watt range and hear no obvious problems, you're fine. I just wouldn't worry about breaking an Acme if you're doing things right.
J o e y