Members Unalaska Posted September 22, 2014 Members Share Posted September 22, 2014 Looking for a way to mount 2 ev sx300's on an on stage lighting stand. Basically the stands go up 10ft and that's the part I need, I've got nice speaker stands but they don't get higher than 6ft really. I've found these On Stage SSA3 1.5" to 1 3/8" adaptor (goes on top of he stand) On stage sa7920 dual stand adaptor (speakers sit on this) Options Link to comment Share on other sites More sharing options...
Members hfc7713 Posted September 22, 2014 Members Share Posted September 22, 2014 I have a couple of 12ft lighting stands that will fit my JBL PRX's without adapters - they are the same diameter as speaker poles. They are not expensive and certainly not the best quality but I have been using mine for a couple of years and they are still going strong. http://www.musiciansfriend.com/pro-audio/musicians-gear-lighting-stand Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 22, 2014 Members Share Posted September 22, 2014 That high, be darn sure they are stable enough. Lighting stands are usually rated for not a whole lot of weight when up high. You are looking at puttingup ~80 lbs give or take. Link to comment Share on other sites More sharing options...
Members JV90 Posted September 23, 2014 Members Share Posted September 23, 2014 I've use and mount 2 active speakers on a heavy duty lighting stands, I've got the hercules Heavy duty light stands: http://www.herculesstands.com/lightsspeakers/lightsspeakers.html And the onstage dual mount adaptor, and on the hercules stands they work very well and you can raise above 6 feet with it Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 23, 2014 Members Share Posted September 23, 2014 6' is a far cry from 10 feet by the way... Link to comment Share on other sites More sharing options...
Members onelife Posted September 23, 2014 Members Share Posted September 23, 2014 A lighting guy that I work with lashes his stands to the wall whenever possible. Link to comment Share on other sites More sharing options...
Members JV90 Posted September 23, 2014 Members Share Posted September 23, 2014 Well you can raise the hercules stand with the cranck more than 6 feet (we don't use feer over here, We use meters instead, so on mine the top of them would be like 3.2 meters all the way up, that would be like 9 something feet agehorse, but for me is to high, but it can be done) Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 23, 2014 Members Share Posted September 23, 2014 I wouldn't do it. I don't think the crank mechanism is really rated for that much weight either. They may be all plastic gears too. Scary. Link to comment Share on other sites More sharing options...
Members BillESC Posted September 23, 2014 Members Share Posted September 23, 2014 I use ST-132 crank stands that go to 13.5' and a twin mount from Quik Lok several times a year for festivals. Here's one of three towers I used a couple weeks ago for the Bay Seafood Festival. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 23, 2014 Members Share Posted September 23, 2014 Bill, what's the load rsting ofthose stands, and have you ever seen the stand sway in the breeze? Link to comment Share on other sites More sharing options...
Members Audiopyle Sound Posted September 23, 2014 Members Share Posted September 23, 2014 The ST-132s are pretty solid for use as outdoor speaker stands. They also have an adjustable leg so you can level them on uneven ground. Rating is 220 lbs, although like most stands I would not consider putting that much up on them. http://globaltruss.com/ProductDetails.aspx?ItemNumber=227&MainId=4&Category=41 For a lighter load as Unalaska is describing I have used Ultimate TS99B or TS99BL with a K&M 24105 fork, sandbagged of course. Link to comment Share on other sites More sharing options...
Members onelife Posted September 23, 2014 Members Share Posted September 23, 2014 I use ST-132 crank stands that go to 13.5' and a twin mount from Quik Lok several times a year for festivals. Here's one of three towers I used a couple weeks ago for the Bay Seafood Festival. Scary - the base does not look wide enough to me. Is the stand secured in any way or is it just sitting on it's base? Link to comment Share on other sites More sharing options...
Members Unalaska Posted September 24, 2014 Author Members Share Posted September 24, 2014 I have some older crank stands that are rated 220 per stand. I've used them with 12" box truss and hung lighting from them before. I don't have any rigging stuff for the EV's and am not planning on suspending them anyway. I might be able to use the crank stands since they'd be the most sturdy option, I think they take a 1" square box on inserted into the top. I'll see what the forks have on the now. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 24, 2014 Members Share Posted September 24, 2014 I think it would be wise to see how the rating is determined. It may not be at full extension. Genie SuperTowers have a different rating depending on the load location. In any kind of breeze, no way would the rating be valid at full extension, not even a close try. Stage roofs and trusses are rated in much the same way, all depending on the loads (both vertical and horizontal wind loads), type (point versus distributed) and location of loads. Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted September 24, 2014 CMS Author Share Posted September 24, 2014 Lawsuit waiting to happen. Check ratings, and then check your business liability insurance. Link to comment Share on other sites More sharing options...
Members BillESC Posted September 24, 2014 Members Share Posted September 24, 2014 If there is a threat of wind, the speakers are lowered. For the last 13 years I've used these stands with various speakers four or five times a year without any issues. Link to comment Share on other sites More sharing options...
Members Pro Sound Guy Posted September 24, 2014 Members Share Posted September 24, 2014 Something falling with that weight from 13' can kill someone. Safe or not always keep in mind anything up on a pole can be knocked over by drunk waterbags Link to comment Share on other sites More sharing options...
Members Unalaska Posted September 25, 2014 Author Members Share Posted September 25, 2014 Thanks bill, that's pretty cool. Link to comment Share on other sites More sharing options...
Members BillESC Posted September 25, 2014 Members Share Posted September 25, 2014 Perhaps a professional football tackle could knock it over. When extended, the legs create a 5' 3" diameter base. It is very stable. Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 25, 2014 Members Share Posted September 25, 2014 5' base with a 13' moment arm and a little sideways force is not very stable. If in a protected area, it's likely fine, but not everybody operates their equipment in protected areas. Link to comment Share on other sites More sharing options...
Members Audiopyle Sound Posted September 25, 2014 Members Share Posted September 25, 2014 They are very stable. Nobody is going to hit it at 13' off the ground. Link to comment Share on other sites More sharing options...
Members wesg Posted September 25, 2014 Members Share Posted September 25, 2014 This is an interesting problem. I estimate that the top of the pole will see a force of about 31N with a 30 mph wind, and 85N with a 50 mph wind. 31N is equivalent to the gravitational attraction between the earth an object weighing 7 lbs. I estimated that the speaker pair had a maximal surface area when projected onto a plane of 5 sq ft, and I estimated that the coefficient of drag was that of a typical motorcycle+rider with a full fairing (0.6). I haven't a clue how to calculate how much force would be required to tip that sucker over. First year physics was over 20 years ago, and I didn't actually pass. Although I had really good lab marks. Wes Link to comment Share on other sites More sharing options...
Members agedhorse Posted September 26, 2014 Members Share Posted September 26, 2014 Use the sum of moments versus zero method. Force moment of 13' moment arm x wind load force versus gravitational force operating on leg moment arm. The 13' moment arm would really be the hypatanuse but for steep angles it's pretty close to 13' Link to comment Share on other sites More sharing options...
CMS Author Craig Vecchione Posted September 26, 2014 CMS Author Share Posted September 26, 2014 Yeah, the moment arm increases from the vertical leg to the hypotenuse leg of the triangle as the assembly tips. Then consider that the hypotenuse is a variable length depending upon whether the assembly is tipping against two of the three legs or just one. WWSCS? (what would Sheldon Cooper say?) Link to comment Share on other sites More sharing options...
Members Dookietwo Posted September 27, 2014 Members Share Posted September 27, 2014 I use the global ST-132 as well. http://globaltruss.com/ProductDetails.aspx?ItemNumber=227&MainId=4&Category=41 They work fine for my 2 EF500p speakers as well as others I have put on them , Yamaha MS400 or EV SXA250. Link to comment Share on other sites More sharing options...
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