Thoughts on this light... World's smallest RGB DMX light

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on a side note, I know a lot of fixtures use the internal y- connection for the DMX thru, but I thought I read that the spec calls for all thru's to be actively regenerated? maybe this changed in a later revision of the spec....
the spec doesn't call out for active regeneration --- if it did, then if some fixture was powered off or broken, all subsequent fixtures down the line would lose signal. the THRU for almost any receiver is simply Y splitting the IN connection. That's also why you need a terminating resistor at the of the line over long runs to avoid reflections, because the signal is connected from the DMX transmitter all the way THRU to the last fixture.
 
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Jan 5, 2009
Keep in mind that the XLR-4 is commonly used in the video industry as a power connector for 12VDC, so you may wish to stick with the standard pinning for those which I believe is pin 1 ground and pin 4 +12V. I assume you would then be using pin one also for the DMX line Shield? or will it be unshielded, which in theory should be fine. Personally I would use an RJ 45 for power and data ala PoE, use the same pins for power as PoE and require a home run for each light, back to a splitter box that actively splits out to the lights and accepts a XLR-5 in and thru for standard DMX lines. Does this push cost up...well yes some. however cat 5 is cheap, and compliant, and so is that method of splitting. OR just have that box do all the DMX and send only the voltage to power the leds to the fixture.....I could see a fixture now that is only slightly larger than an RJ45 jack.

Personally I like the XLR-5 because with the exception of some stereo mics, I have not encountered much else that uses it. The XLR-3 invites one to use improper cables, and the same may be true for the XLR-4 (any you would encounter would either be for r dc power or some proprietary interface, neither of which are likely to be the correct type of cable and in the dc power case may only have pins 1 and 4 wired. anyway just some things I would consider.

on a side note, I know a lot of fixtures use the internal y- connection for the DMX thru, but I thought I read that the spec calls for all thru's to be actively regenerated? maybe this changed in a later revision of the spec....
XLR-5 may be (almost) exclusively lighting (except for the stereo mics you mention) but it is absolutely forbidden to use the second pair to carry power (unless you can fit your power needs in the voltage/current levels provided by an EIA-485 signal).

If you would use it to carry power then you'd have the same problem that you sketch with XLR-4, while XLR-4 as mentioned before is also used a lot for strollers (clearcom headsets also use them, but I don't recall anyone ever using an extension for the headset they extend the box usually).
 

thesigma

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Feb 25, 2008
Ddin't mean to imply that I would have power on an XLR5, though as I reread it I can see how you thought that, sorry.

RTS intercomms also use XLR4 and 5 for headsets(opposite gender to clear com though), 5 for stereo of course or Binaural (2 different channels, 1 in each ear).

anyway, for power and signal, I'd go RJ-45 and Cat 5, even tough it does limit the ability to daisy chain the lights.

Thanks,
 
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Power over Ethernet (PoE) is more or less out of the question as it handles at most 25 watts, most likely single fixture we design for theatrical use will take up at least 5 watts... so completely redesigning the system for PoE where only a 5 light daisy chain just doesn't seem worthwhile. XLR4 on the other hand is capable with a lot more power, and as many have mentioned, there are plenty of power supplies in the industry that support it... we may choose this route.

OR... we can just make the next theatrical fixture like most fixtures you find on the market: we supply a XLR5 (or XLR3) signal in and thru connection (it will still be Y split like the image above... but as we discussed, it is DMX compliant because the split is only per fixture and kept short) and a 12V DC connection, and we give you a 12V AC adapter... so connectivity wise, it's the same as 90% of standalone DMX fixtures, it's only a smaller light.
 
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one other thing I forgot to mention about this product --- it was originally designed for set decor in dark settings (such as haunted attractions or dark rides) where the size and low power of the fixture is more important than its brightness and durability of plugs. I'd imagine for most road shows and theatrical uses, this light just isn't bright enough. So for this particular product, if we took out the requirement for super durable headers that may be run over a few times by crew members and considered it ony for permanent installations --- I don't see any reliability issues when the customer is hard wiring the system with RJ45 or similarly shielded cable (I recommended the TRS extensions to Bill because he wanted to speed up his install, otherwise I would be recommending hard wiring). Sure it will take longer to install than simply plugging it in, but most lights fixtures for decor purposes simply has bare wires coming off the fixture which requires hard wiring anyway.

I believe the comments given in this thread are very valuable when we use it for a new product designed more for theatrical use and we consider all the different scenarios of road shows, portability, ease of connectivity, durability, etc, etc... we will be attending LDI this year and looking at more products that are available in this market before we finalize on a plan for a future theatrical product.
 

n1ist

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If you use connectors that are normally found in theater, I would follow the standard pinouts (or at least design it so no harm would occur if you plug it in with other devices. For RJ45, that means signal on 1/2 with ground on 7/8. For XLR4, pick one of the pinouts that scrollers use (unfortunately, there are different and incompatible standards here) and watch out for the standard 24v supply. As mentioned. XLR5 is mainly used for DMX and that doesn't allow power, and XLR3 doesn't have enough pins and is common for both data and sound.

In the animated Christmas lighting world (and likely the Halloween world) the most common connector is the RJ45, either using the 1/2 pair for DMX(Lynx and family, standard DMX) or the 4/5 pair for RS485 (Renard, LOR) mainly for reduced cabling costs (lots of cables when you get hundreds or thousands of channels of control).
/mike
 

TimMiller

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If I were designing a light for touring and entertainment I would put XLR3 and 5 on it. I would have a built in power supply to prevent people from losing them or plugging in the wrong one. Also the plug in power supplys take up lots of room on power strips if you were to use them and are not very easy to secure to battons. I personally hate xlr4 because not every place sells it when you get into a bind. Also having to run every fixture back to the power supply like someone mentioned is a terrible idea due to the massive amount of cabling involved and the long distances theaters usually require. RJ45 is nice but you are limited to your power. If you went with a built in power supply you could also have rj45 in and out. I would also make it where you could address each fixture directly from the fixture and not have to carry along some type of dongle to do it. Also I like when fixtures especially LEDs have power lights on them. I also like it when fixtures have a dmx light on them so you can track down problems quickly.
 

DuckJordan

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While that is great for a theater fixture this isn't their main market. Please read the thread before posting. It just adds clutter.

Sent from my ADR6300 using Tapatalk
 

xander

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If I were designing a light for touring and entertainment I would put XLR3 and 5 on it. I would have a built in power supply to prevent people from losing them or plugging in the wrong one. Also the plug in power supplys take up lots of room on power strips if you were to use them and are not very easy to secure to battons. I personally hate xlr4 because not every place sells it when you get into a bind. Also having to run every fixture back to the power supply like someone mentioned is a terrible idea due to the massive amount of cabling involved and the long distances theaters usually require. RJ45 is nice but you are limited to your power. If you went with a built in power supply you could also have rj45 in and out. I would also make it where you could address each fixture directly from the fixture and not have to carry along some type of dongle to do it. Also I like when fixtures especially LEDs have power lights on them. I also like it when fixtures have a dmx light on them so you can track down problems quickly.
You've just listed every standard LED "PAR" light on the market and quintupled the size of the fixture being discussed.
 

TimMiller

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Houston, Tx
That's what I would expect out of a touring light. Now install is a different world. I would install a removable terminal block on the back of each fixture. You can use a 5 position and make pins 1&2 power then 3-5 dmx. For daisy chaining fixtures you just screw in 2 sets of cable. The fewer connectors in an install the better. I would put a little power led on the back of every fixture to simplify troubleshooting. Also not having to buy any connectors really cuts down on the budget. Next I would make a powersupply that can be mounted on the wall so you can daisy chain power through the units. If you wanted you could have several circuits supplying power depending upon how many units they have and as another addition the powersupply could have a built in data splitter. I would also make the cabinet that houses the powersupply and possibly splitter modular so you could add onto the system and to make replacing components easier.
 

thesigma

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Feb 25, 2008
If you wanted you could have several circuits supplying power depending upon how many units they have and as another addition the powersupply could have a built in data splitter. I would also make the cabinet that houses the powersupply and possibly splitter modular so you could add onto the system and to make replacing components easier.

Pretty much what I described earlier, except I suggested Cat5 with RJ45's, cheap, readily availible, and quick to swap.
 

thesigma

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Feb 25, 2008
With a terminal strip you are not limited to wire awg. You can find strips that will accommodate anything. You can't put 18 guage wire into a rj45 connector.
This is true but if you are running a home run back to a power supply/data splitter, it should suffice for such a small light, and again, is dirt cheap. And since this is the "worlds Smallest RGB DMX light" we are talking about, an RJ45 would be much smaller than any 5 position trminal strip I have ever seen. using RJ45/Cat5 you could probably chain 4-5 fixtures, depending on current draw, however two rj45's are about tghe size of a 5 pin terminal block, so.....in a daisy chain your solution would allow more fixtures with a higher gauge wire, for sure. however, is there any 18 AWG 5 conductor cable that is DMX compliant? or are we now running a data and power cable? I'm sure you could find some cable that might work siamese cable or a cable designed for AMX/Crestron touch panels perhaps....this gets costly though.

I've got to say honestly I don't like any of the solutions, Glad I don't really have a need for a light that small. Honestly, it seems like the original solution works fine so maybe they should just stick with it. Though Cat 5 is spec compliant for dmx data, perhaps not if you are also sending power on it? It's not defined in the spec, but you could do it on the spare pairs. at least the cable is twisted pair and the proper impedance.
 

dvsDave

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//negative-mode
USB only goes up to 5m (15').

You'd need some logic in the fixture to inform the USB controller about the power needs, and 100W is only @ 20V or possibly even slightly more.

//end-negative-mode
 

beardedbil

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Jul 8, 2010
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I just wanted to chime in here quickly and let you know my experience with installing/programming almost 75 of these small RGB lights. First off, Quan, the creator of this light, was nice enough to travel out to our install location to make sure everything went smoothly. That is first rate customer service in my book!

Secondly, I was actually surprised how quickly and easily the lights went up and were wired together. We ended up using around 7 different legs of DMX to control the whole haunted attraction. The lights worked perfectly from the get go and have some great features that you just do not find in other less expensive LED DMX lights, such as flicker (candle effect or other), color macros, etc.

Another great feature is the lights will hold the last look if the DMX signal drops out. Overall I was very satisfied with the way the lights operated and now have confidence that even though the pigtails on the lights are not standard procedure, they do work quite well and we had no problems controlling any of the fixtures. Quan makes a great product and is a great guy! I would definitely recommend doing business with Darklight.
Best,
Bill Rod.
Dark Tech Effects
DARK TECH EFFECTS
 

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