Want to identify my speakers

I bought a system from an old friend who knew very little about stereo equipment but trusted a friend that it was a good buy. I bought it from him a few months ago and am delighted with it but would like to find out the history of the speakers. The system consists of a Macintosh 2100, a carver M400 magnetic amp, a Adcom tuner/preamplifier and a Nakamichi crossover. The speakers are bi-amped and have a JBL logo on the crossover controls. They have 15" woofers, a horn mid and a an odd shaped tweeter (possibly piezoelectric) . Their size is 46x26x16. Any help you can give will be much appreciated. If you would like pictures etoinshrdlu@Mac.com