jbell wrote:I know, I know....
Everything I hang is minimmum 1/4" diameter or heavier hardware. However codes are codes. The theory is that either the mounting points, or the connection material itself can vibrate lose, fail, etc... Look in any commercial building, every light fixture, every everything has a safety cable...
For your yearly fire marshal / codes inspection, they 'should' look for it.
Even with turnbuckles, I use jam nuts and locktite.
If you run a lightweight cable (1/8" would do) in/out of one of your ports, through a hole drilled in a horn mouth brace -- that would be easiest, cleanest.
BTW -- I love church's... pretty cool what you did for them.
For your rear mounting points, I'm a fan of locking carabiner's
Thanks for the input on mounting hardware. I'm thinking smaller turnbuckles in back may do the trick since I have 3-4" between the bolts in beam and the bolts in the speaker. A smaller than 5" turnbuckle up front would also fix things there.
It was a great upgrade and the cost relative to a commercial solution providing the same quality is an absolute bargain.
Tim Ard wrote:
JBell, I've never been able to find locking carabiners locally that are approved for overhead lifting. Where do you get yours?
Eastern Mountain Sports, LL Bean, any sporting goods store that sells climbing gear.
Not 100% sure on the overhead, but Home Depot had carabiners and the screw down rings when I was looking at hardware. My original plan was to use s-hooks in back. In retrospect I think I'd rather have hardware that all locks together.
I was also pretty amazed at the zip ties but I will admit that I think the guy (woman) who invented them should get a Nobel Prize. They are great for a lot of things but overhead rigging is not one of them. They do deteriorate over time and most of the stress ends up on the tightest tie. Their use exposes the church to unneeded potential liability. I work in construction management and to amplify the earlier point, even over head light fixtures are always required to have safety chains.
A great source of rigging information can be found on the JBL Pro web site. In it they describe how the steel cables need to be made up and loads figured as well as proper pull angles for flyware. Some interesting articles there also on array theory as well as a lot of marketing hype. Check the technical library there.
mlkras wrote:I was also pretty amazed at the zip ties...
A great source of rigging information can be found on the JBL Pro web site. In it they describe how the steel cables need to be made up and loads figured as well as proper pull angles for flyware. Some interesting articles there also on array theory as well as a lot of marketing hype. Check the technical library there.
gdougherty:
What is the crossover frequency to the OT12's?
And dimensions ( volume of the area )
* I saved your pics to show others for a replacement idea: for an existing flown speaker system that been in place for 16 years ( using lag bolts and aircraft cable BTW ).
With the T48 on the bottom we cross at 100Hz. Ceiling's about 25ft at its highest, room is basically a square with everything turned 45 degrees and the side and back corners cut off, about 100ft on the diagonal. Room seats about 250-300. If you have a wide room then the stereo setup works well. If we didn't have the beams trisecting the ceiling I might have considered something like a mono center array of 2-3 DR200's with melded arrays. I do like the coverage that a stereo setup affords. If I wasn't worried about hanging too low and blocking the view from the side 2 DR200's per side would cover a wider vertical area and be a bit more ideal.
