ETCnet resources?

[ChrisB_SanDiego]

Or a typical early generation DMX system and its equipment installed in a theater is weaker than a typical new network system for lighting in a theatre because.....its 20-30 years older. I have both in a lot of projects and I'm certain with both installed at same time and of of similar quality, the DMX will be working longer with less maintenance than the network.

I am curious as to why this would be? do you think it might have to do with the increase in build quality and shielding from the cables? or possibly the overall increase in signal noise pollution that we have now as opposed to 30 years ago?

Some of what you're saying has merit, but your basic premise is still wrong: Ethernet is more limited by distance than DMX, and DMX is actually a "stronger" signal both in terms of the actual voltages on the wires and in how tolerant it is of any problems along the way. In part this is precisely because it is older and slower (since higher speed signals are more picky about how they're being carried). It's true that RDM has some additional requirements over standard DMX, but you only need to worry about those requirements if you actually plan on using RDM. Devices that don't follow the standard are going to be a problem no matter what protocol you use to talk to them, and likewise, Ethernet cables that are abused are just as likely (if not more likely) to fail as DMX cables. Neither of those issues are points in favor of one protocol over the other.

Obviously it would be silly to blindly assume that everything will magically work in all cases where the standard says it theoretically could, but it's just as silly to make equally blind assumptions that something won't work just because it's old. DMX is better at some things than Ethernet. Ethernet is better at some things than DMX. The standards for both act as a guide on how to make the best use of whichever one fits a particular application.

Forgive me if I'm wrong but when I am talking about DMX being weak and old, I'm solely talking about protocol in and of itself, not the actual cable, For that sake, I should not really have mentioned cable length in the same post and I didn't mean that cable structure should dictate the protocol used so I apologize for that. My mention of cable length has to do with the fact that I have witnessed on my own rig, both with an install and portable setups, packets running into each other, causing issues, as well as rf interference on long runs of DMX cables and I, have not had this problem with ethercon cable... again that's been my experience, maybe others have opposite experience. Bills voice would carry more weight than mine since he's probably worked on more installs and consultations than the total gigs that I've worked with largely the same equipment (I'm currently almost to 400 gigs).

The voltage statement doesn't really carry weight...we're talking about 24awg on ethercon vs 22awg on dmx cable when the dmx protocol is only a floating 12v with an average constant of 4.5v (however on the smaller cable there is more resistance so i can see that causing a shorter overall run) but i hold to my statement that no matter the type of cable, im not going near 100m before amplifying the signal again... but it has been long since accepted that dmx is outdated. The DMX protocol can only handle 512 address and not necessarily a full 512 if you added on the need for 16bit plus revision 2 RDM (if your like me and actually use all that feature), there are star curtains out there that use 3 full universes..., this was the very purpose of sACN and ArtNet etc... if we are talking cable quality than its still an "it depends" as cable quality and manufacturer come largely into play as ethercon has become much more ruggedized than your typical category cable.

They are all tools, which means it's about which tool the LD thinks is better for the job. I personally think we have outgrown the dmx protocol, and i must not be the only one to think that way as we see more and more fixtures directly accept sACN and ArtNet at the fixture via ethercon.

I apologize. I didn't mean to turn this forum into a debate, it's all just really interesting to me, but I know I still have a lot to learn.
Cheers

 

[BillConnerFASTC]

Without quoting, I'm simply suggesting 30 year old hardware is less reliable than brand new.

Can you ship less information on a DMX line than a network line. Sure. That doesn't make a DMX weak signal. DMX is really quite robust, and probably more reliable than network. Sure, it predates other protocols.

Quartz is old. Doesn't mean it's not the best source for some applications. Things can always be stronger, doesn't make them better, especially if it was already strong enough.