Well I made some very good progress last night. Moved the speakers out so that there's an additional foot between them, pulled the subs out from the corner a bit and lowered the crossover frequency until I just started to hear/feel the "chest thump" diminish (68 Hz) then dialed in the gain and I gotta say, it's sounding very, very good. All the tracks I was testing with that were the most problematic now pass with flying colors. The bass drum in Chris Issak's "King of the Highway" has the perfect amount of weight, punch and resonance. The bass drum pattern in Jack White's "Lazaretto" with all its syncopated beats has perfect timing so that the groove is solidly locked down. Janis Ian's "Breaking Silence" now has that articulate, punchy and full bass drum getting out of the way so the track has all of its space and atmosphere uncluttered by excess bass energy and the deep percussive elements more clearly defined in the sound stage with improved sonic clarity so that the attack of the drum strike has better tactile impact. And bass notes are clearer, as well. Toto's "A Thousand Years" has a killer bass line that is synced to the bass drum and prominent throughout the song, providing weight and movement that anchors all the other instruments which are playing with a lot of space between notes. The bass guitar also plays with small steps between the notes, providing an excellent opportunity to hear any notes that may be out of balance in volume and weight. If your system is recreating melodic bass at a very high level, this one should be a treat for anyone's ears whether you like the music or not. I would imagine it to be a jaw dropper with very good open baffle bass. Hell, it's a jaw dropper in my system and it's a monkey coffin showroom with my current set up.
Bottom line, I can't wait to get back out to the studio to listen to some music...and THAT's when we know we are in a good place with our rig's performance. I'll need some more time to confirm it, but at this stage I'm hearing my system play at perhaps the highest level I've ever achieved with any system. The LS6's are pretty remarkable alone, but when bolstered by a solid, dense, authoritative and unobtrusive bottom end that seems unencumbered by the room, truly create a music listening experience that excels on all levels. And as much as I'd love to have a pair of trio stack OB servo subs, I gotta admit that these JBL 4648 bass bins, with a little tweaking and dialed in to the room and ststem, are truly fantastic.
Much thanks to all who chimed in. Now I can start having some fun tweaking the LS6's with cable swaps, electronics swaps, isolation/damping footers , etc.
