Jump to content

Two speakers on one speaker stand


Recommended Posts

  • Members

I have stumbled across a need that I'm not sure I know how to solve. There are times the band I do sound for plays in a venue that is quite wide and large. We played there this past weekend and I used two JBL SRX715 speakers each hoisted on a global truss ST-132 speaker stand per side. Plenty speaker stand to hold the speakers, and enough rig in terms of volume. The problem came in coverage. The SRX715 is a 75 degree horizontal horn, and did not cover the width of the room. I really need 2 SRX715's per side. Not for volume but for audience coverage.

So,,,,

How do I get 2 SRX715's up on one ST132 speaker stand? Weight is most likely not a problem in that each speaker is 48 pounds, and the stand is rated to hold in excess of 200 lbs. Also this config is only for indoors so no wind factor to worry about.

 

Has anyone done this? Is there a piece available that would fit on the stand's 1 3/8 pole, and extend out with 1 3/8" mounts so both speakers can be set on the stand?

I called Global Truss and they do not make one. Suggested I have one custom fabricated. Before I go down that road I thought I'd ask if anyone has suggestions.

These speakers are not the flyable version so I'm thinking I cannot hang them from a T-arm.

 

Thanks in advance for the replies.

Link to comment
Share on other sites

  • Members

The On Stage SS7920B's I use with my two pairs of PR-10's are 18.5" between mounts and rated at 100 lbs so would theoretically work. In practice I don't know how you'd get them both up there as putting them up one at a time you'd need someone to hold the first one from tipping the stand over while you tried to get the second one up - you'd need crank stands for sure! I've used a pair of stands together with heavier cabs before, seems like it would be a better choice for these cabs of yours :)

Link to comment
Share on other sites

  • Members

These are pretty hefty crank stands. Typically what we do is load them cranked all the way down. (Not very difficult with the SRX715's as they only weigh abot 48 pounds. Easy job for 2 guys) then crank them to height. (about 8 feet off the floor to the bottom of the speaker. Works well for the room we play in. The room has a 15 foot accoustic tile ceiling.

Using 2 pair of stands would work, but clutters up the side of the stage, so not a good option for this situation..

Link to comment
Share on other sites

  • Members

Well, the On Stage SS7920B's are only about $30 shipped for two "used" ones from here:

http://cgi.ebay.com/On-Stage-SS7920B-Dual-Mount-Speaker-Bracket-USED_W0QQitemZ360189870312QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item53dcfd40e8&_trksid=p4999.m20.l1116#ht_2884wt_1020

My "used" ones look like they may have only been used once at most. You won't really know how they will work for you until you try them out :).

Link to comment
Share on other sites

  • Members

I run 2 Yorkville EF500p tops on the same tripod and they are rock solid. With 178 lbs on each tripod it is very hard to move them. In this picture the bottom of the speakers is at about 6 feet. I had a cert. welder manufacture the T-bar for safty. It has a slight angle to it too properly splay the speakers. I believe your speaker has the same flyware so you could do the same thing with M10 eyebolts that screw into the top of your speaker.

Works fine.

 

Dookietwo

Link to comment
Share on other sites

  • Members

I have seen more difficulty mounting 2 speakers on one stand... notthat it can't be done safely, but that it takes more effort and attention to detail to do so.

 

Last night, I needed 2 speakers per side and I used 2 stands nested which gave exactly the same result but using 2 smaller stands with powered EV SX-100a's.

Link to comment
Share on other sites

  • Members

Personaly I don't like putting one speaker on a stand (too much chance of drunk trippage oan or tippage). Of course I do it because my job dictates I do. I also try to make it as safe as possible (I.E. where the tripod legs are pointed and putting strips of white gaff on the protruding legs).

 

Two speakers on one pole is asking for trouble. Sure the pole might be rated at 150lbs but I'd bet that's a rating with the weight balanced straight down the center of the pole (not lateraly at all).

 

Did you know that there are 3 lawyers for every engineer in this country?

 

Just food for thought.

Link to comment
Share on other sites

  • Members

Personaly I don't like putting one speaker on a stand (too much chance of drunk trippage oan or tippage). Of course I do it because my job dictates I do. I also try to make it as safe as possible (I.E. where the tripod legs are pointed and putting strips of white gaff on the protruding legs).


Two speakers on one pole is asking for trouble. Sure the pole might be rated at 150lbs but I'd bet that's a rating with the weight balanced straight down the center of the pole (not lateraly at all).


Did you know that there are 3 lawyers for every engineer in this country?


Just food for thought.

 

There is many factors that determine how stable a tripod is.

 

The more weight that is on a tripod the harder it is for it to reach the point where it falls over.

 

If it takes 25 degrees to reach a point where it will fall over its allot easier to reach that with 10lbs on it than 200lbs.

 

(in the case of crank up stands) How high the speakers are in relation to center of gravity. A speaker cranked up 4 feet is allot harder to knock over than one cranked up to 11 feet. (something I'd never do)

 

How far the legs are apart. A larger stand has a much larger "footprint" than of course a smaller one has. This helps determine the degree at which the tripod will no longer be stable and falls over and how hard it is to reach it.

 

Even with two speakers on a tripod the weight is still in the center until the tripod has been tilted in such a way as the center of gravity is too much.

 

I did allot of testing with my tripods and found some interesting things.

 

The lean testing I did with a double load per side. 400lbs.

 

Its been awhile so look these numbers up as they could be wrong. In tripods 15 degrees is considered the max tilt angle for testing. If your tripod falls over at or before a 15 degree angle it is considered unsafe for the load on it.

If a tripod is tilted to 15 degrees and is let go and maintains the load without failure it is rated for the load. Most companies worth a darn will give their tripod a 1/3 rating. If it is rated for 200lbs it will maintain 600lbs static weight.

 

It just the case of my T-bar system I found I could tilt it to 15 degrees and let go with no problems repeatedly. (400lb load) This is at the max height that I would ever use the tripods at. Also it took ALLOT more effort to make the tripod reach 15 degrees with 2 speakers mounted on it than 1. This is with the Bottom of the speakers at a given height. In the case of 1 speaker being supported by a single top hat in the center of it at the same height it was scarey how it flopped around and wanted to fall over sooner. For me I would much rather have 2 speakers hanging Down from a T-bar than mounted up on a T-bar by the top hat mounts.

 

In my humble testing 2 speakers at a given max height on the tripods I used were allot more stable,harder to reach tilt over angle and recovered better when tilted and let go. Again at the max height I would ever use them at compared to 1 speaker. I have had girls "pole dance" with my tripods and not even budge them. To be honest durning testing with the legs set at max spread and the speakers at the height that I would use them at it took 2 people to lean them enough to get them to the point where they wanted to fall over. Allot greater than 15 degrees. I don't feel a 300lb drunk slamming into them could budge them. Most likly he/she would break an arm/face...:facepalm: Or at most slide the tripod a few inches left/right.

 

*Notice* This is the results I found with my setup. Its up to the person using a tripod to determine if his or her system is safe to operate.

 

Dookietwo

Link to comment
Share on other sites

  • CMS Author

Sorry you are correct. I forgot this is an international board. The point of safety should still be a concern though no matter where you are.

 

If your location is listed (and it is) then "this country" should not have to be expressly stated. Geez moody, maybe you need a beverage; I've got some Franziskaner Heffe Weis in the fridge. I'm not sure what it was "filtered" through, though. Stop on by and we'll down a few and chill...;)

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...