mounting loudspeaker to grid

[Chris Jolocon]

Hi,
My school's auditorium recently underwent a renovation. We have a dead hung schedule 40 1.5" pipe grid, 4' spacing. Grid is about 17' above deck. I want to see if it is possible to safely mount two loudspeakers from one of the battens, ideally the one just upstage of main curtain, keeping the speaker just below the grid.

I've looked at various mounting brackets, such as the Yamaha BBS251. It allows for a maximum angle of 45-degrees, however I might want the speaker to angle further downward, almost straight down, as in loudspeakers that are mounted in drop ceilings at stores and offices. Any suggestions? I am flexible on which loudspeakers to mount, although I was initially thinking something like Yamaha CBR 10" or 12" or equivalent EV product. Speakers would be used as monitors for when we do musicals to pre-recorded backing tracks, or in the case of an assembly with students on stage, upstage of main curtain where it is difficult to hear the main system. These would not need to get particularly loud, for instance in the event of a rock band on stage requiring monitors I would use floor wedges.

An alternative I am considering is using eye bolts on bottom of each speaker and suspending them from the grid, probably in the downstage corners (just upstage of where each side of main curtain is drawn), maybe about 9' above deck. Any thoughts or suggestions?

 

[jkowtko]

I've hung speakers from the overhead grid before ... SRM450s, which are about 50lbs each. I used pipe clamps with posts pointing upward and set a thick plywood form (roughly 2' square by 1" thick) over each post to create a suspension platform for fly-mounting the speakers with 3-point mounts. It worked pretty well and provided lots of flexibility for positioning the speakers.

Just remember to safety-cable your speakers to the grid!

 

[BillESC]

I'd suggest a purpose built answer. Electro Voice's ZLX-12 12" two way speaker has a mounting bracket (ZLX-BRKT) that would allow you two clamping points and adjustable angles.

 

[TimMc]

Loudspeaker models designed for installation use frequently have the best selection of mounting accessories and may feature more built-in suspension points.

 

[Chris Jolocon]

I like the ZLX and its bracket. Would you suggest using 2 C-clamps on the pipe grid, then the post side, instead of going through the yoke bracket of lighting fixture, goes through the center hole top and center hole bottom on the main part of that U bracket? I'm wondering whether the hole would be correct diameter, or if there is a particular c-clamp or post to use. I would be sure to safety the loudspeaker itself to grid. Thanks.

 

[RonHebbard]

I like the ZLX and its bracket. Would you suggest using 2 C-clamps on the pipe grid, then the post side, instead of going through the yoke bracket of lighting fixture, goes through the center hole top and center hole bottom on the main part of that U bracket? I'm wondering whether the hole would be correct diameter, or if there is a particular c-clamp or post to use. I would be sure to safety the loudspeaker itself to grid. Thanks.

@Chris Jolocon My vision is impaired due to a stroke. Are there not two holes in the bracket which you could enlarge to 1/2" plus clearance and utilize two standard lighting C clamps each with a 1/2 - 13 standard attachment bolt?
Alternately, is a there a single hole on the center line of the bracket that you could enlarge to 1/2" plus clearance, further stiffen with two steel 1/2" fender washers ( one above plus one under ) and assemble the entire clamp plus fender washers and bracket assembly with one, longer, 1/2" - 13 grade 8 bolt?
As ALWAYS add one or two independent and redundant safeties, preferably attached to a forged shouldered and threaded eye bolt threaded into an approved hanging point supplied within the cabinet by its manufacturer.
NOTE: More and more off-shore manufacturers are providing Metric (rather than Imperial) T-nuts or threaded steel attachment points within their cabinetry.
Toodleoo!
Ron ( That's as close as I'll post about overhead rigging here on Control Booth. ) Hebbard @What Rigger? and @egilson1 Would you care to comment??
EDIT: Insrted "to" where inadvertently omitted.

 

[TimMc]

I like the ZLX and its bracket. Would you suggest using 2 C-clamps on the pipe grid, then the post side, instead of going through the yoke bracket of lighting fixture, goes through the center hole top and center hole bottom on the main part of that U bracket? I'm wondering whether the hole would be correct diameter, or if there is a particular c-clamp or post to use. I would be sure to safety the loudspeaker itself to grid. Thanks.

The question about attaching other things to the EV bracket should be answered by EV in the manual for the bracket, or with a follow up email to EV/Bosch. I'd not use any hole (like the center hole you're talking about as they are *structural parts of the hardware*) unless EV says that is acceptable use of their product.

For temporary hanging from pipe/truss I like to use a half-coupler like the Light Source Mega:

http://www.thelightsource.com/products/mega-coupler-with-flat-head-bolt-123 rather than use open C-clamps.

 

[What Rigger?]

Without seeing the space, I'd be reluctant to offer pointers on how to do this. So, I'll default to the standard CB answer: consult a professional, don't guess/approximate. Know for sure.
Definitely don't go the DIY route.

Chris, got any pictures we could see?

 

[BillESC]

I would use two C clamps or half couplers. For safeties, you could replace one of the four bracket screws at each end with a rated Eye Bolt and use safety cables to the batten.