another 24 hrs has gone by and leaves don't look worse for wear at 14 inches. might drop lights down another 3 or 4 inches and keep a close eye on them. I just wonder how far you can drop the lights before the outer edges of the grow area lose significant light (drop off). Maybe that's not an issue with 1000w and a 4x4 area.
just keep a eye out because the top leaves might lose their green if it's too close think it's called light burn