LED and incandescent mixed?

[Jon Majors]

I am looking for suggestions and recommendations. I work at a high school auditorium and our first electric is dead hung. It has a row of fresnel fixtures with barn doors. It is a pain to get a lift up there to replace a burned-out lamp. The rest of our plot is a mixture of ERS and Par 56 incandescent fixtures. Would replacing the dead hung 1st electric with LED fixtures pose a concern, specifically with color mixing and blending with the rest of the electrics? We do not have a DMX relay, just 3 pin stage dimmers. If not, are there any fixtures you would recommend for this application? Our stage is 52' and proscenium height of 26'. Thanks in advance!

 

[Lextech]

Sure, mixing LED and conventional is done all the time. LEDs do require clean power so you would need to either replace a dimmer with a relay or find another way to power them. As for DMX if you can't run a hardwire, there are both fixtures that accept wireless DMX or wireless receivers that put out DMX. As for fixtures, you will get lots of opinions as to what to buy, however, I really suggest you do your homework and find 2 to 4 that are in your budget and get demo units and shoot them out in your space. ETC and Chauvet both have people who hang out here and should be able to direct you to someone in their network who can facilitate this. That being said, make sure you have a console that makes using LEDs easy. Yes you can run high channel count fixtures on an Express, but you probably don't want to.

 

[Jon Majors]

Sure, mixing LED and conventional is done all the time. LEDs do require clean power so you would need to either replace a dimmer with a relay or find another way to power them. As for DMX if you can't run a hardwire, there are both fixtures that accept wireless DMX or wireless receivers that put out DMX. As for fixtures, you will get lots of opinions as to what to buy, however, I really suggest you do your homework and find 2 to 4 that are in your budget and get demo units and shoot them out in your space. ETC and Chauvet both have people who hang out here and should be able to direct you to someone in their network who can facilitate this. That being said, make sure you have a console that makes using LEDs easy. Yes you can run high channel count fixtures on an Express, but you probably don't want to.

This is the type of response I wanted to hear. We have an ION, and I am experienced with using wireless DMX. However, I need to research the whole relay thing as I am unfamiliar.

 

[Lextech]

What are your dimmers?

 

[Rob]

One of the nifty (patented) features of the Cognito console is when you dim generic LED fixtures (anybody's), it introduces a red-shift so they better emulate the tungsten fixtures in your rig. Some higher-end fixtures have an on-board mode to do this too.

 

[EmilBarnabas]

See if you can get the school system electrician to install a 20-amp, 120V outlet at/near the 1st electric. You can use that to power all of the LEDs you put on that pipe.

 

[Jon Majors]

See if you can get the school system electrician to install a 20-amp, 120V outlet at/near the 1st electric. You can use that to power all of the LEDs you put on that pipe.

Fantastic idea! Would you have them switched controlled on the wall?

 

[Les]

Fantastic idea! Would you have them switched controlled on the wall?

Absolutely. Your fixture's power supplies will thank you. Just be sure to put it in a spot where it won't get accidentally turned off during a show (or mistaken for worklights).

 

[microstar]

Another option is the ETC UFR2 DMX-controlled relay. That way you can turn the LED power on/off via DMX from your console and not inadvertently have someone leave the power on or off.

 

[gafftaper]

Unfortunately, it appears ETC didn't record Tom Litrrell's "Layers of Light" presentation. That presentation talks a lot about theories of how to blend LED and Incandescent lights. This one is the sequel a year or so later. It starts out with some of the concepts in "Layers of Light" and then goes to other places. But it's a very educational view of what ETC thinks about how to incorporate LED's into your rig.

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[LesWilson]

We are a small school with both tungsten and intelligent fixtures. Perfectly normal thing to do. Each of our pipes have traditional dimmers and four 20amp fixed power circuits. We power off our LED fixtures at the breaker panel. If you can't do that then yes, you should have a secure switch someplace. I use both Meteor and Doug Fleenor DMX controlled relays to control power to other fixtures such as fog machines, mirror balls etc.

 

[josh88]

We're a roadhouse that runs a mix all the time. All of our on stage wash units are moving led's and we use altman phoenixes for high side color washes and led cyc units. That being said we still have kept everything we replaced with led's in storage because we still have some shows that require all incandescent. Most shows coming through that use our plot don't care but some are very particular.

I will also note that led's do want clean power and its bad practice and can cause damage to run them on dimmer power rather than constant power.... BUT we used to run the Altman's on parked dimmers with no issue for years, and still run everything on normal dimmers with ColorSource relays between the dimmer and the fixture. We have repaired some cheaper units that had led failures but anecdotally our etc rep said its more of an issue with brands that use cheaper components and so far that has held true, the better built stuff hasn't been bothered by dimmer power. It's smarter and safer to not take the risk of damage to your gear, but the sky won't fall down just because something is getting a chopped sine wave.

 

[Sean]

I will also note that led's do want clean power and its bad practice and can cause damage to run them on dimmer power rather than constant power.... BUT we used to run the Altman's on parked dimmers with no issue for years, and still run everything on normal dimmers with ColorSource relays between the dimmer and the fixture. We have repaired some cheaper units that had led failures but anecdotally our etc rep said its more of an issue with brands that use cheaper components and so far that has held true, the better built stuff hasn't been bothered by dimmer power. It's smarter and safer to not take the risk of damage to your gear, but the sky won't fall down just because something is getting a chopped sine wave.

Wait, so you're powering a relay with a dimmer, and then turning power on/off to your fixtures by switching the relay??? This isn't gaining you anything, other than an added point of failure. What kind of dimmers do you have?

 

[josh88]

Wait, so you're powering a relay with a dimmer, and then turning power on/off to your fixtures by switching the relay??? This isn't gaining you anything, other than an added point of failure. What kind of dimmers do you have?

We're also using them for dmx distribution. We've got sensor racks but being a roadhouse with a shell we have enough shows that don't use our rep plot or electrics (5 permanent and 8 drop boxes) so things move around enough that the added point of failure without the need to swap relay modules around in the rack is what the pay grade above me decided was the option they wanted to go with.

 

[microstar]

We're also using them for dmx distribution. We've got sensor racks but being a roadhouse with a shell we have enough shows that don't use our rep plot or electrics (5 permanent and 8 drop boxes) so things move around enough that the added point of failure without the need to swap relay modules around in the rack is what the pay grade above me decided was the option they wanted to go with.

All of this just makes my head hurt trying to figure out what is being accomplished, but I'm glad it works for you.

 

[orpheus85]

You can also get Mains-Dimmable LEDs. The Altman Pegasus Fresnel, would be a drop-in replacement for what you currently have without needing any new infrastructure. Then you would basically have the same set-up as you have now (except no lamp changes).

If you had Source Fours as your ERS fixtures, you could retrofit them with the Source 4WRD II (also mains dimmable).

Both of these options are also DMX controllable should you upgrade the infrastructure in the future.

 

[almorton]

It's interesting that the product video for the Altman doesn't specifically show it dimming down to zero slowly on mains dimming. I wonder at what level it snaps off and on - how far can you dim them to zero before they "pop" off, and at what level do they suddenly pop on. ETC are honest about that in their video, and you can see that the curves aren't the same, too.