The root I suppose goes way back, I worked for an electronics distributor/retailer, we sold Electro-Voice pro, I was smitten by a 15" 2-way and how incredible the EV horns/compression drivers sounded. I just couldn't convince my wife road carpet cabinet went with our décor. So I opted for a set of Infinity Kappa &'s, different sound but still enjoyable.
Since that time my exposure to JBL was a few models in big box stores and car audio, nothing I'd consider for "high end" home use.
I found a local installer who carried the Synthesis, I heard a couple LS models & the Array 1400's and came away with respect. The 1400's I had a chance to buy but I couldn't get the imaging I wanted in my room and my EL34 monoblocks didn't feed them like they wanted.
Hit fast forward again, different system and the dealer brings in a set of 4367's. He brought them over to me for a listen and to help break in, they are still here and have switched ownership to me
.They took a good while to break in to where the compression drivers smoothed out and the bass response smoothed out, at first a big bass hump. I think the dealer thought he may have made a mistake, he thinks you can tell basic character out of the box. I disagree in speakers for the most part. The 4367's are the speaker if you want the music to sound live, bass sounds like it is being played in the room, drums have the crack and dynamics, no distortion even when driven at high volume. I love these speakers. Vocals are natural and sound like the performer is in the room. My only criticism the 4367 does not play as low as other floorstanders I've used, the bass is deep but in recordings with low bass I am familiar with I can really detect the roll off. Other than those few recordings though I don't really miss that last octave or so, the 4367 delivers dynamics in spades.
My wife still isn't thrilled with the look and size of the 4367 but she relegated my sound/media area to the lower level when we moved into our current house, so I stood my ground, LOL.