Flying DR arrays

Helpful hints on how to build 'em, and where to get the stuff you need.
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N.Webber
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Re: Flying DR arrays

#16 Post by N.Webber »

Turntablist,

Your initial idea is nice. If I was to design a system from scratch, I would go the three point bracket method
(have a look at HK's Cohedra: http://www.cohedra.de/komponenten.php?m ... 01820c4c0#)
The bracket system certainly has clear advantages over the wire hangers (but as noted, done right costs a magnitude more…),
the obvious would be the inherent solution to the front edge pivot issue and of course the ability of ground stacking.

Fish has referred and clearly explained some of the key safety features that need to be imbedded into the proper design of an array'able cab.

A safe and quick attachment system is one. A simple bolt through the brace and into the cab's wall
(presumably a 'T' nut on the inside…) is far from 'safe'.
In most if not all commercial array flying systems there is some type of positive locking pin that goes through two static plates,
having the attached/removable brace sandwiched in between them, and held by the pin.

The bracket system also should be enclosed within the cab's outline and preferably holding all the movable parts in a neat and practical manner.

Of course, many other obvious aspects such as load ratings, duty and safety margins, material choice,
fool proof operation and more need to be addressed and fully calculated and thought out.

By the way, setting up 'my' system is indeed a one man operation (though can go somewhat quicker with additional help).
All attachments of the cables/flying bits is done while the cab is resting on the floor (or on top of another cab),
and only when everything is hooked up, the cab is lifted by the hand crank.

:)
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Turntablist
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Re: Flying DR arrays

#17 Post by Turntablist »

The reason why I wanted the cab to be easily lifted into place was because I was inspired and attracted by EAW's NTL720. You can hang a cab and secure it in 20-25 seconds.. To stack a cab on the ground and hang it from there is an easy enough solution so I've scrathed the thought of anything similar to the NTL720.
Here's a video of their solution: http://www.eaw.com/products/NTL720/vide ... wn_lg.html

Sandwich brackets on the sides is what I've thought of lately too. The tough thing about DIY cabs though (and especially such complex builds as DRs) is that there will be slight differences between the cabs. A three point hanging solution is therefore required and I would suggest a cable and L-tracks in the back. It would be much more convenient in many manners than a bracket in the back would be.
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N.Webber
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Re: Flying DR arrays

#18 Post by N.Webber »

Yep, this one is really nice and clever. I like it too.
But it's also well beyond the scope of DIYing...

Only thing against cable attachment (even if only for the third/back point) is it will not let you ground stack.
I find myself stacking pairs of my 290s often (on top of the subs) and because they only have provisions for wire flying
I have to use a set of spacers to get the different splay angles.

As said, If I would do it again I would go the three point bracket way.

Edit: The DRs Butt ‘creek’ is actually perfect for that third point…
Now my hand is kind of itching again… :wink:

:)
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Turntablist
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Re: Flying DR arrays

#19 Post by Turntablist »

All points are very true.

I hadn't considered using the space in the crack! If one could find a good way to secure the bracket in the crack it would be a very nice option..
And so my head starts to gnaw this subject again.. :)
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Re: Flying DR arrays

#20 Post by N.Webber »

So here's my concept.
This is only the bare idea. If it ever develops to practical stage
it will need to be designed and checked to meet all engineering aspects and such.

Key features:
1. Three point bracket support
2. Can be retro fitted to existing cabs
2. Fully retractable when not used

Some details may not appear in the drawing but I have most of them figured out.

Here goes:

Image

3D of the 'flipping' back bracket:

Image

:)
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Gregory East
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Re: Flying DR arrays

#21 Post by Gregory East »

Curious what the design includes for wind loading. Gravity seems very well under control but wind, not so much. Granted, it's not a permanent structure so the standard would be lower here in NZ, likely similar in Israel, but in USA I expect it's supposed to stand up in a storm...
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UROK

Re: Flying DR arrays

#22 Post by UROK »

Similar to Greg: is a sub required for stability?

If so would that not necessitate violating the Fitzmaurian Law of Subwoofer Placement for some applications? I guess outdoors it's easy to split by over 56 feet?

I'm also a bit confused because in my mind for outdoors isn't doubling the subs to mid-tops ratio recommended because boundary loading is lost in most cases? Even if split by over 56 feet wouldn't one want the horn mouths coupled together?

The products I have seen such as this:

http://www.made-in-china.com/showroom/u ... Truss.html

..have much longer legs (although they are often photographs with split subs).

Flying 6 DR280s with a pile of dual T60s would attract the sort of attention I am after! :twisted:

Interest more than knowledge is behind my question so forgive me if I seem to be challenging much superior skills etc than mine - just working things through (albeit slowly :conf: ) :noob:

This weekend I saw some impressive Chinese trussing. Very well-welded.

Nid, do you think your mounting hardware could be combined with the sort of Chinese product I linked to?

Thanks, guys. As ever, a pleasure to participate and learn from sorted individuals! :clap:

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Re: Flying DR arrays

#23 Post by N.Webber »

Gregory East wrote:Curious what the design includes for wind loading. Gravity seems very well under control but wind, not so much.
If you're referring to my last post regarding the alternative flying hardware, this design was motivated (also) with ground/base stacking in mind, so should be rigid enough and hold up also in severe wind conditions (tied down properly of coarse).

As to the original hardware idea (or this last one) and L.A.M.Post (or any other self-standing hanging structure...) holding up in high(er) winds - appropriate safety measures should be applied, such as heavy ballast at the base and guy wires to keep the array from swaying.
UROK wrote:Nid, do you think your mounting hardware could be combined with the sort of Chinese product I linked to?
Sure, all lifting apparatus boils down to a lift hook that can take any array by its top frame. My suggested flyware is DR oriented and deals with interconnecting the cabs, but the whole (DR) array could hang off these structures just like any other array out there.

:)
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- 6 DR290
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- AT, TAT
- Tuba 48
- 2 WH10
- Truck Tuba
http://www.boniton.co.il
http://www.bt-12.com Balanced Tilting Sounds Better...

UROK

Re: Flying DR arrays

#24 Post by UROK »

Many thanks, Nid.

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