Control/Dimming DMX Distribution

[tyler.martin]

Hey Guys,

I had a thread a couple of months back about the DMX Distribution in my building.

The Issue is that I have 10 DMX in ports scattered around the facility. They all terminate at the Dimmer Rack. However I cannot figure out how. If you have 10 DMX lines coming together to control one rack, you could not just twist all the wiring together, and then connect it to the DMX in port on my CD80's. There would have to be some signal merger somewhere in the building.

Anyway, What I need to do is get the second universe from my console up onto my FOH catwalks. I have three of them that are about 80 feet from the ground, I have cat6 patches at each of the catwalks, and cat6 in the booth, what would be the cheapest protocol to convert the DMX to? ACN,Artnet,ETCNet?

Thanks.

 

[epimetheus]

You could do a DMX-over-Ethernet protocol. I'd go for DMX directly over CAT6 though. Do you have access to the patch panels? If so, make sure the ports are disconnected from any switches, and hard patch a path from your booth to the catwalks. You could put in a DMX opto-splitter at the patch panel location or in the catwalks. If you do go the DMX-over-CAT6 (no ethernet) then I'd use different colored patch cables and label them very well so DMX doesn't get accidently plugged into a switch.

 

[JD]

You really want to stay away from unused tail runs that go all over the place. Best to disconnect what is not in use. It's like attaching a bunch of bells to a snare drum. You hit the drum and all the bells ring. At some point, it starts not sounding like a drum. The patch bay is the best idea. Only patch up the line that is in use.

A DMX merger can get expensive as it really is a computer that scans the information from each line, and then forwards the information based on a programmed protocol. (LTP/HTP)

Lots more $$ then an opto-splitter, and if you are only running one board it's a waste.

 

[JChenault]

If you want a separate universe, you probably cannot use the existing cable.

What kind of console are you using? What types of protocols does it support for output? IE if you have a single XLR output from your console for DMX, you will not get a second universe. If you have two XLR outputs, it might be cheaper and easier to just run DMX cable from the booth to the FOH. If you console supports only artnet - then you will be using artnet. ( You get the picture).

For curiosity - what kind of dimmer rack is it? Why do you think the 10 DMX lines terminate in the dimmer rack? Can you see them attached to it in some way?

Why do you want to use a second universe for your movers?

JOhn

 

[pathway]

For your first problem, you don't actually have to use a DMX "merger" to collect all the input lines and merge them (legally) into one. If you don't need to run more than 1 or 2 consoles at the same time, you can use a less expensive DMX "hub" which behaves like a signal "OR-ing" device. It detects a live input signal on any one of its ports and transmits that signal on the other unused ports, giving you additional opto-isolated distribution for the first universe. One port would be dedicated as the dimmer rack output. Both Pathway and Fleenor make 8-port versions of these (Repeater Pro and BIDI8 respectively). Pathway's includes a 9th (master) input that will merge HTP with any of the other inputs. Either way you'll need 2 units if you want to support all 10 inputs. These units are only a little more costly than basic opto-splitters and you get a lot of bang for your buck.

For your second issue, I agree that DMX over the Cat6 is your best bet until you can afford to buy a number of portable Ethernet/DMX nodes, or until you actually need Ethernet at your FOH. Connecting everything via a patch bay gives you ultimate flexibility and the option to send DMX (any universe) or Ethernet to a given FOH jack.

 

[tyler.martin]

I have an express 48/96, currently 1 universe, sent to 2 CD80's.

I want to use the second universe for my scrollers and iCues. I do have access to the networking room at orur building, so I can direct patch the two ports.