Ok so I have one of these and since there's pretty much no information about this pedal or treble boosters on bass I thought I'd pitch in.
What a treble booster does is boosts the hell out of some treble, specifically for the purpose of brightening up old british guitars/amps and distorting the crap out of a tube amp. Though there have been a lot of people to get good results with a treble booster used in conjunction with single coil pickups and brighter amps like Fenders or Vox. But if you're trying to push something with a treble booster that won't push back, you will be sadly disappointed. Also the treble booster, like a lot of fuzzes, isn't supposed to play well with buffers (it's supposed to get very thin sounding) but I haven't tried any buffers to verify this for myself.
You can kind of push certain dirtboxes if they have an amplike enough response to bounce back with the treble booster. It's not the real deal, but I think it sounds kind of cool:
http://media.putfile.com/Germania2
That's the Germania pushing my Box of Rock by the way. It's not translated so well in the soundclip but that sound has some serious bite.
Ok how about just the Germania, with an Ampeg head set pretty clean without it:
http://media.putfile.com/Germania1
You can hear how the Germania pushes that amp hard. The distortion comes from the amp, not the pedal, and has the characteristics of the amp's distortion, kind of ratty and fuzzy. But anyway, take a listen and let me know what you think!