When I played steel string, the BP-100 was my preferred pickup as it worked great on my '28 Juzek. I tried it on a number of other basses without any success at all. So like all pickups, how well it works depends greatly on the bass, strings, set up and player. You absolutely need a high impedance input so a preamp is a must or, if you have a series II Acoustic Image amp, they had high Z inputs built in. I mounted mine in the traditional way with both piezos on top of the bridge. Finding right pressure with the clamps is very important as well. Too tight and the sound is choked. Too loose and all of the bottom end is lost. Use a pair of needle nose pliers to widen or close the clamps. Note: for the basses it didn't work on, it didn't matter where I put the piezos or how much or little pressure I tried with the clamps, it sounded like fingernails on a blackboard).
To hear what the BP-100 sounded like on my '28 Juzek go to my Myspace page and listen to the track entitled "Voodoo Butter." It is the rough mix from the session (it was the mix sent to the drummer's headphones and we found that straight pickup to the drummer's phones worked better for him). It is a little piezo-y but it sounds way better than any other pickup I tried on that bass. Unfortunately, I don't solo on this tune but you can hear the bass pretty well during the guitar solo.
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