DMX control cables
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Topic: DMX control cables
Posted By: Dudecar101
Subject: DMX control cables
Date Posted: 9/16/05 at 3:41pm
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OK, first off, im a lighting designer this year at my school and have been asked to choose a light board for our theatre. SO I chose the ETC Expression 48/96, but supposedly the board has DMX inputs, and i am working in a 19 year old theatre. I doubt we have the DMX inputs, upon looking at the present lightboard (an analog lightboard) I noticed it is a cord that has a screw end and a whole bunch of pins... AM I srewed or is there a series of adapters I can use to solve my dilemna, or am i an idiot and this is a DMX cord ------------- Im a great 11 student whose a lighting designer...if you got ideas...send em! |
Replies:
Posted By: dougb
Date Posted: 9/18/05 at 12:11pm
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The question is what input your dimmer packs need. As soon as you
know that, you can search on the internet for converters. There
are lots of DMX to CMX converters and even DMX to AMX converters.
The last time I bought one was several years ago and a DMX/CMX
converter was around a couple of hundred dollars but I think they have
probably dropped in price. I think you are going in the right direction with the ETC Expression - it seems to be a very popular board - provided you can interface it to your dimmer packs. ETC can probably help you too - this is not the first time this question has been asked. P.S. DMX uses five pin XLR connectors. |
Posted By: Dudecar101
Date Posted: 9/18/05 at 2:18pm
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In the event that the old 20 year old dimmers needed to be replaced, how much do you think that would cost...there are 48 channels and we like to double up the channels so we have two lights on the same channel to give a feel of symetry.
Not to mention the hours of running new cables... ------------- Im a great 11 student whose a lighting designer...if you got ideas...send em! |
Posted By: dougb
Date Posted: 9/19/05 at 11:49am
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Dimmer packs are the expensive part of the solution - I have never
bought new packs and used ones go for $100 or more per channel.
On the plus side, a good dimmer pack lasts forever. Since DMX 512
has been the standard for several years, you can mix and match dimmer
pack manufacturers if you have to. The wire called for in the DMX 512 spec costs over 50 cents a foot. We have had very good luck with Cat 5 computer wire to run our signals 100 feet and slightly more. Many theaters do what you are doing - replace one component at a time. We are a super low cost operation. I let other nearby theaters know what we need and we are usually successful although sometimes we have to wait for it. Our seats were donated by a nearby theater. We bought a used 24 channel light system (light board, dimmer pack and wiring) for $2,000 from a theater that was upgrading and we just bought a five year old velour curtain exactly the size we wanted in almost perfect condition for $200. |
Posted By: Shatcher
Date Posted: 9/19/05 at 3:28pm
| the dealer you buy the board from should help you solve this problem. ETC will help as well. You will like this board. programing is pretty easy to use and ETC makes adapters for everything. |
Posted By: dougb
Date Posted: 9/20/05 at 11:10am
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Just a thought: The DMX specification calls for five pin connectors and wiring (four wires plus ground) but as of today only three wires are actually used (two wires plus ground). You could get 5 to 3 pin adapters (or just wire the 5 pin connectors with shielded two conductor) and use two conductor shielded cables (mike cables for example) realizing that some day you will have to replace them when the spec writers can agree on a use for the other two wires. |
Posted By: Dudecar101
Date Posted: 9/20/05 at 9:34pm
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The ETC is a very nice board, i actually learned how to program and run one this summer at a theatre camp i attended. I like this board and that is actually a pretty good idea, because XLR 3 pin wire is much less than the 5 pin... How does this Category 5 cable system work...cuz your right dimmers are expensive ------------- Im a great 11 student whose a lighting designer...if you got ideas...send em! |
Posted By: dougb
Date Posted: 9/21/05 at 11:25am
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Cat 5 is wire used for ethernet computer networks. It is
unshielded, has 8 conductors (four twisted pairs) and has a
surprisingly wide bandwidth that seems to work well for our lighting
system. For what it is worth, I am beginning to see ethernet based lighting networks - the signal is sent as an ethernet signal (generated by a computer rather than a light board) and not converted to DMX till the last few feet. |