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A Small Truss System, For Two Point-Source Speakers?
A Small Truss System, For Two Point-Source Speakers?
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Old 3rd December 2018, 11:50 PM   #1
Cableaddict is offline Cableaddict
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Default A Small Truss System, For Two Point-Source Speakers?

Ive just obtained a used pair of EAW KF394s, and will be using them for my "local" rock band and small-event DJ work.

Ive always had my point-source boxes on standard tripods, with my subs clustered in the center. However, because the dispersion of these horns is 90x45, I think it will be important to angle them downward a bit, and to be able to adjust that angle for different rooms.

SO, Im considering using a yoke system, but I'm worried about how much room and set-up time it might consume. Most really small trusses are rated for only lights, while most bigger trusses are serious overkill for my needs.
----------------------------------------------------

My question is, whats the simplest, lightest, smallest way to get away with this?

Is there a SMALLISH, easy-to-deal-with truss system that would work? This truss would have to hold two 70 lbs speakers, plus about 50-60 lbs of lighting . (It would replace my current, very weak lighting truss.)

I cant figure this out, because truss weight ratings tend to be for evenly distributed weight, but my speakers could go just inside or outside the tripods, thus putting much less strain on the horizontal truss itself.

Again, small, light, and easy to setup are the keys. I cant be carrying 12 diameter square trusses, and insert pins and locking wires for 20 minutes before every gig.


So, has anyone dealt with this?
Any suggestions?
Pros & cons of this basic idea?
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Old 4th December 2018, 12:43 AM   #2
MAAC0 is offline MAAC0  Portugal
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Think of a football goal like truss. The problem here is when You hang the speakers, it will tend to fall towards You if You stay at the front because of balance. what You need here is a large base at the bottom or some 45 angled legs in order to maintain the balance like this.


What is Lighting Truss? Lighting and Stage Truss Structures Information


Unless Your truss rods are very thin the 12'' You have should handle the load.
If You put the speakers near the vertical sections (one at each corner), or even attached to the vertical sections, that's the point of best capacity load... but I'm not an Engineer..

Last edited by MAAC0; 4th December 2018 at 12:51 AM.
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Old 4th December 2018, 12:52 AM   #3
Cableaddict is offline Cableaddict
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Quote:
Originally Posted by MAAC0 View Post
Think of a football goal like truss. The problem here is when You hang the speakers, it will tend to fall towards You if You stay at the front because of balance. what You need here is a large base at the bottom or some 45 angled legs in order to maintain the balance like this.
Good point & I certainly agree. I've seen some of those "goal post" systems, and while they look nice, they definitely do need a lot of weight on the bases if you want to hang more than a few lights.

- But I'll be mounting the horizontal truss structure on crank stands. (I should have mentioned this.) I'll most likely use the Duratruss DT-3800L, which holds 175 lbs per unit and has a 4' leg spread.

As for the truss-strength itself:
I know that a 12" square-format truss will work, but that's a bit too large for me. I'm hoping I can get away with an 8" square, or ideally an 8" triangle format truss. With a ten foot total truss, if the vertical supports were at the outsides, and the speakers hung at about the 1/3 nd 2/3 marks, an 8" triangle probably would be dangerous. However, I won't be doing that:

My tripod poles will be spaced about 6' apart, with a solid 6' truss section in-between them. Then I will have an additional ~ 2' truss section attached to each side. I like how that would look (framing my DJ or keyboard rig) plus it should minimize the weak center spot, as opposed to an unsupported 10' truss.

Last edited by Cableaddict; 4th December 2018 at 01:01 AM.
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Old 4th December 2018, 01:19 AM   #4
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BTW, Maaco, thanks for that link to XSF.

They have load tables for all their trusses. very helpful.
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Old 4th December 2018, 07:59 AM   #5
chris661 is offline chris661  United Kingdom
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You could use heavy-duty tripods and a good speaker tilter. One that keeps the centre of gravity consistent while the angle varies.

Example: BT-12 the New Patented COG Loudspeaker Adapter

Chris
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Old 4th December 2018, 10:52 PM   #6
turk 182 is offline turk 182  Canada
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why limit your loudspeaker position to the ends of the lighting truss?
get some independent lifts for your speakers something more like this

Click the image to open in full size.
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Old 4th December 2018, 11:16 PM   #7
MAAC0 is offline MAAC0  Portugal
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This is were I buy all my things. Take a look


Lighting Lift Stands – Thomann UK - Very good service


Penn-Elcom also carries many things. Take a look at their Catalogue.
I have a distributor nearby where I buy handles corners and grills for speakers / racks
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Old 5th December 2018, 11:59 PM   #8
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Quote:
Originally Posted by turk 182 View Post
why limit your loudspeaker position to the ends of the lighting truss?
get some independent lifts for your speakers something more like this

Click the image to open in full size.


LOL! In my dreams, brother. In my dreams.......

That's the same dream in which I have a crew of four lovely 25 year old female roadies, all with trust funds and Daddy issues.
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Old 6th December 2018, 12:05 AM   #9
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Quote:
Originally Posted by chris661 View Post
You could use heavy-duty tripods and a good speaker tilter. One that keeps the centre of gravity consistent while the angle varies.

Example: BT-12 the New Patented COG Loudspeaker Adapter

Chris
Pretty clever. - But I don't like the aesthetics. I think "upside down" yokes look better when the speakers are direct-tripod mounted. (Though that's certainly more of a hassle.)

FWIW, I just bought a pair of those expensive K&M angle adapter / tightener thingies. Tried them today for the first time, and they are probably going back.
They work, but they are tricky to adjust: You have to TURN them in order to adjust the angle, so then you have to rotate the entire stand afterwards. Not so easy with a 70 lb speaker.

Also, they add another foot to the minimum stand height, so it's harder to get the speaker mounted.

They do lock nice & tight, though.

Last edited by Cableaddict; 6th December 2018 at 12:16 AM.
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Old 6th December 2018, 12:10 AM   #10
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Quote:
Originally Posted by MAAC0 View Post
This is were I buy all my things. Take a look

Lighting Lift Stands – Thomann UK - Very good service

I'm in the USA. Still, some of these choices were good to see.

----------------------


I found these guys last night, and am very excited about their products:

6″ Wide Aluminum Mini Truss – Light Design Systems

The strength-to-size ratio is the best I've see, for aluminum trussing.
It looks like their 6" triangle truss is more than I'll ever need. That will pack very nicely!
(Thanks to your first link, I was able to start understanding load points, etc. )

They don't sell tripod adapters, but those are easy to get elsewhere.

Also no black anodized or powder coated, but that's why God invented 2-part paint! (Maybe with Duratex painted on as a final coat, for scratch resistance.)

They also sell those "flat feet" as a separate product, which most truss companies do not. I hate having tripods on stage, but need the ability to "load then raise." so I'm thinking I could get a pair of those 4' long feet, with the 3-pole configuration (for 2" diameter tubing) and possibly drop my tripod feet right onto them. So I'd still use tripods, but not have to ever open the legs.

Last edited by Cableaddict; 6th December 2018 at 12:18 AM.
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