Control/Dimming USB to DMX (drivers?)

[alleytheater]

I've been going through the motions of transferring my theaters lighting system from a dmx system run from a light board over to a computer board. We don't need anything fancy, just a basic 24 dimmer program is fine. More would be better, but we only have so many dmx dimmer packs as it is.

My question is. Is there any reason to use something like enntec over a simple usb to xlr (my light kits use regular 3 pin xlr cables) converter? Also, if a simple adapter like that will work (I bought one from radio shack) where would I find drivers? It's not a matter of the expense. It just seems silly to me to buy an adapter that I have to buy an adapter for. My experience has always been that the more adapters you use the more degraded a signal becomes.

 

[metti]

I am fairly certain that the adapter you purchased at Radioshack is designed to output audio from a computer via USB. This is not the same thing as a DMX adapter and it will not work. Purchase an Enttec Open DMX USB and a 5-pin to 3-pin adapter and you will be good to go. Pass off what you currently have to the sound department since it won't do what you want. 3-pin DMX is not the same thing as 3-pin audio.

 

[metti]

By the way, is the product you purchase this ION MICLINK USB Microphone Cable - RadioShack.com?

 

[BryanKacz]

I'm not clear what you mean about a simple usb to xlr converter, but USB and DMX are different protocols so you need some kind of converter (like the entec box) in the middle to translate the USB to DMX.

EDIT: wow, i guess I took a long time to respond.

 

[Anvilx]

Just bare in mind USB doesn't have as fast a clock cycle as DMX. So while the lowest-end Enttec or Velleman (though that is barely hobby-grade) work, they don't work so well. I can't remember the exact symptoms, but I want to say it's lag. That's one big reason why the Enttec DMX USB PRO is recommended, it has its own IC in it to handle timing.

Sent from my HTC Liberty

 

[gcpsoundlight]

If you want to have a go, jaycar electronics has a USB DMX Kit for around $50 US

 

[itie]

if you are still looking for software to run it i would look at magic-q. it can do a simple fader to dimmer consol or more advance stuff like moving lights. its a free download it just has a learning curve on the more advance stuff.

giovanni

 

[metti]

Just bare in mind USB doesn't have as fast a clock cycle as DMX. So while the lowest-end Enttec or Velleman (though that is barely hobby-grade) work, they don't work so well. I can't remember the exact symptoms, but I want to say it's lag. That's one big reason why the Enttec DMX USB PRO is recommended, it has its own IC in it to handle timing.

Sent from my HTC Liberty

I could be wrong but I am pretty sure that you only start to see these issues once you start working with more advanced fixtures (moving lights, etc). If he can afford the Pro it is definitely worth the price increase over the open but for many applications the Open does fine.

 

[Anvilx]

It just depends on the level of quality that you are comfortable with, for a production that isn't super serious or a one off event the open is probably fine. You get what you pay for.

Specifically what are you going to be controlling today and then what do you see yourself controlling 4 years from now?

Sent from my HTC Liberty

 

[n1ist]

The big issue with the Enttec Open and similar devices is that they depend on the PC to regularly send out the DMX packets; since PCs are multi-tasking, the updating can get interrupted or delayed long enough to cause issues. The Enttec Pro has its own processor that takes care of the regular sending of DMX data; the USB data is limited to sending updates when something changes. The Velleman unit looks like it has its own processor, so it is like the Pro.

Unfortunately, all of these USB dongles use their own protocol for sending data from the PC to the dongle, so you need to make sure your software supports the brand of dongle you are using.

/mike

 

[JChenault]

I could be wrong but I am pretty sure that you only start to see these issues once you start working with more advanced fixtures (moving lights, etc). If he can afford the Pro it is definitely worth the price increase over the open but for many applications the Open does fine.

Not really. With the pc doing all of the work, you may ( Depending on a number of factors) get frequent drop outs. Affects any use not just movers.

 

[metti]

But with just dimmers, would dropouts not really matter that much since the dimmer would just hold it's last state. Unless the interface is frequently dropping out during fades I wouldn't think you would notice.

Disclaimer: I own several Pros and no Opens so I'm not vouching for the functionality of the Open, just trying to learn more about these things.

 

[JChenault]

But with just dimmers, would dropouts not really matter that much since the dimmer would just hold it's last state. Unless the interface is frequently dropping out during fades I wouldn't think you would notice.

Disclaimer: I own several Pros and no Opens so I'm not vouching for the functionality of the Open, just trying to learn more about these things.

My experience was with a SunLite box ( which uses the PC for processing). I believe the box put out 0 values when it droped out. Note - I am working from old memory here and I could be wrong. As I think about how it is probably built, it seems to me that your example would be more likely to be correct, but it is not the experience I remember.

 

[metti]

My experience was with a SunLite box ( which uses the PC for processing). I believe the box put out 0 values when it droped out. Note - I am working from old memory here and I could be wrong. As I think about how it is probably built, it seems to me that your example would be more likely to be correct, but it is not the experience I remember.

If that is the case than that would definitely be an issue. Regardless, the Pro isn't that much more expensive and the OP should buy it.