
My old (early 70s) JBLs are big box 3 ways – 15″ woofer, 1″ horn midrange, and a slot tweeter. I’m currently running them with my aging JVC AV receiver – its a nice unit, but it doesn’t provide much headroom for the woofers. JBLs are very efficient speakers – it doesn’t take a lot of power to run tweeters or mid-range horns, but woofers are power eaters in a decent system, and big woofers are worse. You see, speakers make music by moving air, and it takes lots of power to move a big speaker cone.