CPM Reviews: The Selador X7xtra LED Striplight
by: David Martin Jacques
Copyright © 2007 by David Jacques
Published in the June, 2007, issue of Church Production
By: David Martin Jacques
For: Church Production Magazine
Light Emitting Diode (LED) technology has been with us for several years now. Certainly the promise of LED’s in theatrical lighting is exciting. Along with almost limitless color range and smooth color mixing, LED’s offer enormous energy savings in both power used and overall lamp life. Plus they generate very little heat from the light source. Unfortunately, the tradeoff has been lack of intensity for stage use and the initial high cost for the LED’s.
I have used LED fixtures in several church projects. One in particular was for a church in Texas where the choir sits under a very low 7-foot ceiling. The incandescent lights above the choir were literally burning the top of the choirs’ heads. Men were losing their hair, and women’s wigs were in danger of igniting. Anyway, I replaced these lights with LED fixtures and the difference was remarkable.
LED’s can also be used for traditional theatrical applications, from spot-lighting to lighting drops and cycs. They are also used in architectural applications. I am presently designing a church that uses LED rope lights hidden behind the reveals of crosses. This will offer a soft glow of color behind the pastor.
Selador has been on the forefront of this technology. They have recently introduced the new X7xtra LED Striplight. This fixture incorporates 32 extra-bright three-watt Luxeon K2 LEDs in each foot-length of fixture. This makes this fixture is almost three times as bright as their previous X7 model.
What does this mean? For the first time a manufacturer is realistically claiming that their LED striplight is as bright as standard incandescent stage striplight.
Of course we were skeptical. So Selador sent us an X7xtra-21 LED Striplight for testing at California State University Long Beach. We put this light through its paces in both our light lab and in the theatre under a real production environment.
First, a few basics: LED’s (Light Emitting Diodes) use a completely different technology than incandescent lamps. LED’s are semi-conducting crystals. They produce light in narrow ranges of wavelengths when electricity flows through the crystal. Although they produce some internal heat, there is no heat directly from the light source.
Due to their small size LED’s are usually grouped in an array consisting of numerous diodes. Grouping these together not only produces a more intense light unavailable from a single diode, it also allows the mixture of primary and secondary colors that the designer can blend to an almost limitless palette of hues. In addition, recent developments have tripled the wattage of LED’s from 1 to 3 watts, resulting in a corresponding increase in intensity.
Selador now incorporates a new seven-color LED array in their X7xtra fixtures. These colors include: Red, Red-Orange, Amber, Green, Cyan, Blue, and Indigo. This allows the X7xtra to produce colors that were previously impossible to achieve in an LED fixture. You can now match deep blues and ambers, along with shades of yellow, lavender, and green. In addition to this wider color palette, the X7xtra can produce a wide range of color correction hues from 800K to 20,000K. Pretty impressive…
So how difficult is it to use this fixture? Just hang it, plug the power cable into an available 120V outlet, plug in a 5-pin XLR DMX cable from the lighting console to the X7xtra, and away you go! No dimmers are required as all the data processing circuits are located inside the fixture.
The X7xtra is controlled by seven DMX channels (one for each color). The fixture has a DMX in and thru. This permits you to daisy-chain several fixtures together (to light a drop or cyc, for instance).
This fixture utilizes extremely quiet fans for internal heat dissipation.
Unlike many of their competitors, Selador does not use automatic shut-off or
self-dimming circuits. X7xtra fixtures require good ventilation and sufficient
air volume around fixture housings. This allows for premium LED performance
and reduces the possibility of failure.
All this sounds as if this fixture produces a lot of heat. The fact is that the X7xtra produces very little. The absence of heat produced out of the front of the fixture is remarkable. Although I would not recommend doing this on any fixture, you could place your hand on the lenses of the LED’s without getting burned.
The X7xtra also includes fourteen standard beam-spreading lenses. This allows you to spread the light in almost any direction in ten-degree increments (from 20 to 80 degrees). The lenses can be used to generate square or rectangular beams in almost any size and shape, producing tight beam edges and flat fields of light. You can also order additional frost and diffusion lenses directly from Selador.
X7xtra fixtures come in 7, 11, 21, 41, and 62 inch models. We used a Selador X7xtra-21 on the production of California State University’s production of “Pericles”. Lighting Designer Leah Austin placed the fixture in the center of an electric designed to light the upstage cyclorama. The X7xtra was surrounded on both sides by 300W incandescent striplights. Leah used the X7xtra as a center punch of color for several atmospheres in the show. This allowed us to see just how bright the fixture was in direct comparison to the standard incandescent striplights.
We found the X7xtra to be as bright (and in some colors, brighter) than these powerful incandescent striplights. Remember, LED’s use additive color mixing and no intensity is lost due to absorption through gel or glass media. Regarding color rendition performance, Leah was able to color match the X7xtra to the colors she used in the incandescent strips. (Selador also included a chart that allowed her to quickly match colors to standard gel colors.) This was quite useful when she wanted to have an intense center effect on the cyc using the same color as the rest of the strips. The lenticular lens that Leah used on the 21” fixture made the beam-spread as effective as a standard six foot striplight.
We also tested the X7xtra in the light lab. Our tests confirm Selador’s claims of the fixture’s wide color range. We also discovered that the color mixing from one color to another to be incredibly smooth without any strange artifacts that you get when changing colors in color scrollers or dichroic color changers. The only color that we were unable to mix to was a very deep indigo blue--but this is due to the limitations of the technology, not the design of the fixture.
We did find that in some instances shadows from the subject being hit with the light produced multi-colored edges in shadows. This is due to the multiple light sources. However, this was very minor compared to other striplights. The fixture stayed cool to the touch throughout our testing. We experienced no problems with consistency in colors even when the fixture was on for many hours.
The street prices for the X7xtra models range from approximately $1180 (7 inches) to $7880 (62 inches). The X7xtra-21 that we reviewed is around $2600. Although the initial cost for this technology may seem prohibitive to many churches, when you account for the enormous savings in electricity (using a fraction of the power of incandescent lamps), lamp life (some LED’s are rated at 100,000 hours), and the cost for dimmers (these fixtures do not require external dimmers), the break-even price point may not be as far away as you think.
We are very impressed with the X7xtra. A company has finally produced an LED fixture that outperforms most standard incandescent theatrical striplights, while staying cost-competitive when you look at the “big picture”. Selador’s X7xtra will only inspire other companies to develop competing products that will drive LED prices down further. And we will all be the beneficiaries of that!
David Martin Jacques is a professional lighting designer and consultant. He has designed hundreds of productions in the US and throughout the world. David consults on new worship facilities and renovations. He serves as Head of Stage Design for California State University Long Beach. He can be contacted at email@example.com.