DMX distro

[Tivoli Phil]

Hi Guys,

 

I'd like to hold my hands up early and say DMX confuses me quite a bit, so this is really a begging for assistance post. I'm looking at putting in a DMX distribution system at the mo, and ideally want to put 1 DMX socket in each of the proposed dip sockets on the stage (6 in total) while leaving outputs on the 4 channel splitter free to go to lighting bars etc. What I want to know is can I simply take a line from the splitter to the first socket, then solder another line on to that socket to go to the next socket and so on and so forth (think daisy chaining fixtures).

 

So in short, will this work, or am I simply barking up the wrong tree? Thanks in advance,

 

Phil

[maeterlinck]

Wrong tree my friend. The only way that would work was if you only ever used one of the outputs at a time. f you used 2 or more you would have passive split in the DMX chain and you could end up with either intermittent faults or nothing. The way to do it is to have a line from each place you want a DMX output back to the place where you have the DMX buffer. Then either have all the outputs plugged in and not worry about which you want to use, or patch each time you want a DMX in a different place.

 

Good luck!

[Don Allen]

The cheapest correct way to do it is to run all of your DMX tie lines back to where the splitter is and with four patch leads just patch DMX to the outlets that need it.

 

There is another way to do your six dip trays. Run them in series with a female socket feeding into the dip tray and a male socket feeding onto the next dip tray. Put a short patch lead in each dip tray and when you want to run DMX from a dip tray, remove the short loop through lead and use longer DMX leads to go to what needs DMX and if you also want DMX at another dip tray down the chain, run another DMX lead back to the dip tray. This system uses twice as many sockets and five short patch or loop through leads but satisfies DMX design rules.

 

You could also use a double pole switch to loop through or break the chain but this is open to abuse as people may run a DMX cable from the female socket when the switch is set to loop through. Safer with a short loop through cable.

[MarkPAman]

Don't suppose your splitter is the Stairville one? If it is, read this thread from post 5 onwards, which shows you can actually run 8 outputs from it (& the through), which is almost enough for what you want to do.

[LeeStoddart]

The cheapest correct way to do it is to run all of your DMX tie lines back to where the splitter is and with four patch leads just patch DMX to the outlets that need it.

 

There is another way to do your six dip trays. Run them in series with a female socket feeding into the dip tray and a male socket feeding onto the next dip tray. Put a short patch lead in each dip tray and when you want to run DMX from a dip tray, remove the short loop through lead and use longer DMX leads to go to what needs DMX and if you also want DMX at another dip tray down the chain, run another DMX lead back to the dip tray. This system uses twice as many sockets and five short patch or loop through leads but satisfies DMX design rules.

 

You could also use a double pole switch to loop through or break the chain but this is open to abuse as people may run a DMX cable from the female socket when the switch is set to loop through. Safer with a short loop through cable.

 

Basically agree with Don but a slightly less expensive solution I have seen in one venue... In the dip tray place a female DMX socket and then run a cable with the male connector to the next dip tray. Plug the male connector into the female socket. Then as Dan says you can break into the chain at any of the dip trays. If you only need DMX in one place you don't need to return to the male connector.

 

The only difference between this and Don's approach is that it only takes one socket per dip tray and no short jumpers to get lost.

[timtheenchanteruk]

personally, I wouldnt use Lees approach, the weakest point is the connector/cable, if its short patch cables, they are easy repaired/replaced, with this approach, if/when one gets damaged, theres only so-fay you would be able to shorten to repair it, boxes are a much safer bet.

 

The jumper can always be secured in the dip tray with a short length of cord to stop it being misplaced.

 

last option, and I have no idea on the cost of this, would be buffered DMX sockets, then you could do as proposed by the OP.

[boatman]

At some point in the future Sods law will prevail and you will find yourself needing to use more than one of the DMX outlets at the same time. Install a six-way DMX splitter from the start and cable each of the boxes separately. A slightly more expensive solution at the start but totally future-proof.

[Tivoli Phil]

Hi Guys,

 

Many thanks for all the replies, I did wonder if I was being foolish. I think what I will do is use a larger splitter, 8 channels would probably do, so I will look at the stairville mod mentioned further up. On a related note to this, any recommendations for where to get some decent DMX cable fairly cheaply. I will make up the actual leads, just need the rolls of cable. Currently looking at the CPC pulse stuff.

 

Cheers,

 

Phil

[smalljoshua]

For install where both ends will be terminated in a box, you can use Cat5 cable.

 

Josh

[henny]

For install why not use one of these Link it would save on connectors