5 pin DMX to 3 pin DMX

gafftaper

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5 pin DMX has two lines reserved for future use when the instrument will talk back to the system. So far there are very few things out there that take advantage of that feature. So, many manufacturers have taken up using plugs that just use the three active channels. You can buy an adapter or make your own. Just be aware that DMX cable is much different than microphone cable. If you try to use mic cable for any sort of distance it is likely to degrade the signal and cause all kinds of weirdness. You will also find people who say they use mic cable all the time with no problems but it's somewhere I prefer not to gamble. Use the search function and you should be able to find info on making your own DMX cables. A recent thread discussed using ethernet cable to make DMX cables.

I suggest you read "Practical DMX" by Nick Mosby if you want to understand the wonders of DMX
 

JD

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Pin 1 > 1:
Pin 2 > 2:
Pin 3 > 3:
Pin 4 > no connect:
Pin 5 > no connect:

In case you wanted to make your own. Also, mixing cable types is a bad thing. You can buy pre-made 3 pin DMX cables pretty cheap. Simply sub the 5 pin connector on one of them. The trend right now seems to be 3 pin connectors, but at some point in the future 5 pin will be the norm.
 

jmabray

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Pin 1 > 1:
Pin 2 > 2:
Pin 3 > 3:
Pin 4 > no connect:
Pin 5 > no connect:
In case you wanted to make your own. Also, mixing cable types is a bad thing. You can buy pre-made 3 pin DMX cables pretty cheap. Simply sub the 5 pin connector on one of them. The trend right now seems to be 3 pin connectors, but at some point in the future 5 pin will be the norm.
The problem with this is the standard is, and always has been, 5 pin cables. 3 pin cables and connectors are cheap alternatives to the standard. Is it done? yes. Should it be? not really. at least if you want to hold to the actual standard.
 

Mayhem

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The problem with this is the standard is, and always has been, 5 pin cables. 3 pin cables and connectors are cheap alternatives to the standard. Is it done? yes. Should it be? not really. at least if you want to hold to the actual standard.
Does it make all that much different in reality?

I remember when bare ends and screw down terminals were the standard for speaker connections. Then TRS, then 3pin XLR, now Speakon. Most amps still come out with the screw terminals on them. From what I see in the industry, this is so that people can easily make up adaptors to suit their systems. I refitted all my amps and boxes with Speakon connectors some time back.

Driving on the Left-hand side of the road was also standard (yes, even in the US) until political reasons saw changes in the US and most of Europe. Should this be changed back?

My point is that things progress and just because someone sets "system A" as the standard that "system A" is always going to be the optimal system to use in the future. Besides, the manufacturers obviously do not follow so called standards.

Food for thought.
 

DarSax

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Don't forget to terminate your DMX, either a 100 or 120 ohm resistor across pins 2 and 3
Chewing gum works too.

I have a question, actually, with a probably-obvious answer. You shouldn't use mic cable for DMX applications, but what about using DMX cable for mic applications? If you had enough money, and there was no difference, couldn't you just buy loads of 3-pin DMX and avoid the confusion?
 

jmabray

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Does it make all that much different in reality?
I remember when bare ends and screw down terminals were the standard for speaker connections. Then TRS, then 3pin XLR, now Speakon. Most amps still come out with the screw terminals on them. From what I see in the industry, this is so that people can easily make up adaptors to suit their systems. I refitted all my amps and boxes with Speakon connectors some time back.
Driving on the Left-hand side of the road was also standard (yes, even in the US) until political reasons saw changes in the US and most of Europe. Should this be changed back?
My point is that things progress and just because someone sets "system A" as the standard that "system A" is always going to be the optimal system to use in the future. Besides, the manufacturers obviously do not follow so called standards.
Food for thought.
In reality, no it doesn't make all that much difference. But then why spend the time and money to write the standard in the first place?

The standard was written with 5 pin connectors for a reason [ A) to allow for a second universe down the second pair or B) to allow for device feedback down the second pair - depending upon who you talk to on a given day].

Some moving light manufacturers chose to put 3 pin connectors in simply because they were cheaper than 5 pin. A side benefit was that most clubs and dj's had 3 pin mic cable that could be used in a pinch to get by on. Does that make it right?

The standard is by no means "so-called." It was not something that people just arbitrarily decided to do. Unlike your Speakon connectors, this particular standard was well written, thoroughly researched and agreed upon documents written by a standard issuing agency - in this case, The United States Institute for Theatre Technology - USITT. The standard was written to allow for devices from different manufacturers devices to talk to one another. Before DMX, if you had a strand dimmer rack, you had to have a strand console to run them - an ETC console wouldn't necessarily talk to them without some sort of "Black Box" converter unit. The standard was written in 1990 originally and it was updated in 2004. It has been adopted by ANSI - The American National Standards Institute. This is a real deal thing here.

You can actually download and read the standard if you want by going to www.esta.org and looking under the Technical Standards program.
 

jmabray

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Chewing gum works too.
I have a question, actually, with a probably-obvious answer. You shouldn't use mic cable for DMX applications, but what about using DMX cable for mic applications? If you had enough money, and there was no difference, couldn't you just buy loads of 3-pin DMX and avoid the confusion?

Absolutely. Its like saying not all rectangles are squares, but all squares are rectangles.

DMX cable is of much higher quality to allow for the data to pass through with out any signal degredation. Mic cable is usually of much lower quality. There is no harm that I have ever heard of in upgrading the quality of your mic cable.
 

SHARYNF

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Sep 3, 2006
It is not really a quality issue, it is more the spec of the cable which is different. I know this will cause some disagreement, BUT in my experience, the termination resistor used on standard mic cables resolves the issues, except in cases of very long runs. If for instance you take a standard mic cable and have it properly terminated and look at the wave form on a scope, vs the waveform using dmx cable, the difference is very slight. Today, using Cat5 cable in many cases is more cost effective.

Sharyn
 

avkid

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Most amps still come out with the screw terminals on them.
Not for long, if the international production retooling trend continues. Touchable binding posts have been prohibited in Europe for a while now.
 

TimMiller

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Mar 27, 2007
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Houston, Tx
as far as using 3 pin DMX for Mic cable yes it works. Our sound guys found that out. They keep on stealing my 3 pin DMX cable so i have to steal their mic cable to use as DMX. Crazy sound guys...........
 

Grog12

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So termination.....I've been places that do it and places that don't...what's the advantage supposed to be?
 

Radman

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The advantage is that it absorbs reflected data and makes everything work right. You're always supposed to terminate.
 

Mayhem

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In reality, no it doesn't make all that much difference. But then why spend the time and money to write the standard in the first place?
The standard was written with 5 pin connectors for a reason [ A) to allow for a second universe down the second pair or B) to allow for device feedback down the second pair - depending upon who you talk to on a given day].
Some moving light manufacturers chose to put 3 pin connectors in simply because they were cheaper than 5 pin. A side benefit was that most clubs and dj's had 3 pin mic cable that could be used in a pinch to get by on. Does that make it right?
The standard is by no means "so-called." It was not something that people just arbitrarily decided to do. Unlike your Speakon connectors, this particular standard was well written, thoroughly researched and agreed upon documents written by a standard issuing agency - in this case, The United States Institute for Theatre Technology - USITT. The standard was written to allow for devices from different manufacturers devices to talk to one another. Before DMX, if you had a strand dimmer rack, you had to have a strand console to run them - an ETC console wouldn't necessarily talk to them without some sort of "Black Box" converter unit. The standard was written in 1990 originally and it was updated in 2004. It has been adopted by ANSI - The American National Standards Institute. This is a real deal thing here.
You can actually download and read the standard if you want by going to www.esta.org and looking under the Technical Standards program.
Read the standard some years ago and you are missing my point. Standards are written at a certain point in time. Things progress, times change and so on. DMX as a standard versus the connection as a standard? Which is the essential part? Don't remember calling it a "so-called" protocol either. Don't get me wrong, I am not trashing the protocol but I do question the romantic notion of holding on to five pin connectors when in 99% of applications there are two redundant pins. I would be more worried about the manufacturers that decided to reverse the polarity of their DMX than those who chose to save on the cost of the connectors.
 

JD

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North Wales PA
Regarding terminators.
They should always be used even if you are not having problems. I know you can set up a DMX system and most times if the cable run is short, everything will work fine, but... what is going on in the wire is a lot of trash noise from echoes generated at every junction on every light or dimmer. What works on one setup may not work on the next. The system may work fine one minute, but do something a little odd the next. (and so on) What does it cost? An XLR connector, a 120 ohm resistor and about 5 minutes to assemble. Hardly worth chancing a show for $5.

As far a 3 vs 5, The 5 pin DMX cables will prevent the sound company from "borrowing" your cables! ;)
 

Thomas

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Durban, South Africa
Don't forget to terminate your DMX, either a 100 or 120 ohm resistor across pins 2 and 3
The only thing I terminate is Martin Color400s, because unless you give them all the love they need they'll give you endless hassles, and even if you do, they'll still give you endless hassles...

I have no problems not terminating, and I'm running wireless and opti-splitters all over the place, into 40-odd fixtures somtimes... guess going wireless and isolating does help with noise...
 
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Footer

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The only thing I terminate is Martin Color400s, because unless you give them all the love they need they'll give you endless hassles, and even if you do, they'll still give you endless hassles...
I have no problems not terminating, and I'm running wireless and opti-splitters all over the place, into 40-odd fixtures somtimes... guess going wireless and isolating does help with noise...
Not even going to bother with this one...