Why Crazy Prices paid for Pioneer 100 JBL L100 AR1 AR3 AR3A

Large Advents still sound good. Heard the JBL 100s new- thought they sounded shrill and boomy. YMMV

Large Advents still sound good. Heard original JBL 100s. Sounded shrill and boomy. YMMV

People that rave about Pioneer speakers will also wax poetic about "vintage" Radio Shack speakers.  They're all over the audio Facebook pages and get very gnarly if you challenge their beliefs.  Forgive them.  They are just boneheads who don't know any better.

Interesting and timely thread as my circa 1978 AR14 speakers were just packed off to the University of TN for the third time today. I first took them in 1978, my oldest son had them there up through his graduation in 2019, and now my youngest moved into the dorms this morning. The one constant is that the AR14s still sound pretty damn good. Crisp highs and tight bass with what was the flattest response curve over the entire response range was their calling card. Though my current system far surpasses them I still very much enjoyed listening to Pink Floyd and Jackson Browne with my younger son over the past couple of months. A Yamaha integrated to drive them was his high school graduation present since my older son had taken the Kenwood integrated that drove them for the past 40 years to grad school - the AR14s were too big to fit in the car headed across country so they passed down to little brother. 
AR14 is a 2-way toward the bottom of the line back in the day with a 10” woofer, 1-inch dome tweeter in a sealed enclosure. I had the woofers re- papered and the crossovers updated about 20 years ago. I paid approximately list price for them in 78 - $320 for the pair. A quick google suggests that would be about $1280 in today’s dollars (4X) and I’m not sure you could beat them today for that cost. 
YMMV.