Although I've addressed this to Steve, I would welcome any responses from others in the know.
As you know, the L101 is a floor speaker with a furniture finish granite top. This dictates that the speakers be seated in their vertical orientation. At your suggestion, Steve, I did raise them off the floor (albiet on a pair of wooden chairs) - just to hear the effect, which was an improvement. The local JBL repair guy (who sounded quite knowledgeable) quoted me $150. each to refoam the LE14As (ouch) because of the manner in which they were glued to the underside of the cone. That's for another day as they're working just fine now.
He also suggested that I raise the front of the speakers to improve on the LF output. I blocked them up on 2x4s and he was right.
This weekend, I intend to follow your original suggestion of getting them about a foot off the floor (chairs were too high - besides, we had to eat. Life brings tough compromises.) My plan (and here is where I need your input) is to get 8 4x4x10" posts (4 per speaker), on which I will mount a 3/4" platform of the same dimension as the base (13 1/2 w x 10 3/8 d).
1. Should I cut out the center of this platform to allow LF escape?
2. Should I cover the back and/or sides to direct the LF forward?
If properly finished, this stand should make for an attractive and practical element. There may be a need to tie the front posts to the back at the bottom, (barstock?) but I hope not.
I value your input and that of any of our other cabinet enthusiasts.