That's easy...the boss fmb-1 is a pedal that duplicates a fender type sound. there's also some multi-effects processors that also simulates fender type sounds. the digitech bp355 and the zoom b3 is one of them. perhaps these sound samples should help you out on how they sound. check them out. http://www.bossus.com/go/vpb-2/
On that link, select bass pedals on the choose a style section. and then select the boss fmb-1 on the alternate set-up section. and below that, there's a rhythm and lead option that lets you hear 2 different demos. and if you like, you can click on the other pedals to hear how they sound with the boss fmb-1.
Zoom b3 http://soundclick.com/share.cfm?id=11902390
Digitech bp355 http://soundclick.com/share.cfm?id=10294700
These links are from demos I've made on soundclick to help talkbass members on how certain multi-effects processors sound. if you don't mind multi-effects processors, check out these sound samples and see if any of these multi-effects has the sound you're looking for.