Cree LR6 Fail

Posted: October 9, 2014 in Reviewed - Poor Performers
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In my previous entries regarding the Cree LR6, I’ve noted the good and bad sides of the product in some detail. I’ve noted my dissatisfaction with the brightness of the diffuser, which has caused me to first apply plastic trim rings to add a little cutoff, then later, to simply not turn them on. Dimming performance over the years has been disappointing as well. No dimmer I have found has dimmed them satisfactorily, most cause them to flicker. The latest from Lutron, designed specifically for LED/CFL sources, did not fix the issues, so I simply gave up. Rather than remove these expensive retrofits ($65.00+ each), I chose to do what many of us do when caught in a  quandary – stopped using them at all. Estimating these were not used more than an average of 1 hour a day for the last 4 years, total operating time is less than 1,500 hours. I’ll give them 2,000hrs, assuming that when they were first put in place, I used them more than I did as we grew tired of their glare and flickering under dimmer control.


LR6 installed in kitchen 2010. Note that all of the units appear to be of the same neutral color and uniform to one another. The color from the fixtures initially was quite nice, even though the brightness was always objectionable.

It became quite obvious that Cree chose to design this product to excel in efficacy, at the cost of aesthetic appearance and visual performance. Over the years they have made excuses for this by stating it was their intent to produce high angle brightness to “fill” rooms with light. This is the old “Volumetric Lighting” dodge that others have used (Acutity uses this term now) as an excuse for  the appearance of brightness in diffused optics, stating it removes the cave effect and improves visual brightness in a space. I’m not a proponent of this, nor do I agree with its basic logic. Visual brightness is uncomfortable, reduces visual performance, and creates a sense of institutional aesthetics to space. I see no reason to use high angle brightness throughout a space to light the perimeter walls, which is what is proposed in the volumetric argument. If you want the walls lighted, then use wall washers or perimeter wall lighting. In the rest of the space, brightness above 45 degrees must be controlled to reduce glare and veiling reflections on work surfaces and displays. The argument that this is no longer necessary due to the anti-reflective nature of modern displays is simply a marketing game of distraction. Veiling reflections can appear on any surface, including smart phones, magazine pages, desk surfaces, even ink on mate paper. There is no case to be made for accepting high angle brightness, period. Volumetric lighting is a sham that should be called out for what it is – lazy design targeted at achieving high efficacy (fixture efficiency) by eliminating proper optical and brightness control features that negatively impact total lumen output.

In an effort to reduce the offensive brightness of the LR6, I created a simple plastic ring trim for the LR6, which was presented in the 52 in 52 project back in 2010. It helped, but was a band-aide job to be honest.

That all said, I have recommended the LR6 retrofits to others over the years, specifically in commercial applications where the brightness issues would be less irritating or problematic. They work well in commercial truck-stop restrooms, and the local Walmart toilet, for example. I’ve also seen them in retail dressing rooms, with some success, and a couple of gift shops in hotels, as well as a few hospitality applications. Some look fine, and the product well suited, others have been awful. That’s the nature of products sold to save energy first – at all costs.

Now to the Fail
This leads to the next installation of the LR6 saga. After less than 2,000 hours of on-time, I noticed s decided shift in color of two of four units. One shifted to pink, the other to green. The remaining two remained steady and neutral. This condition worsened so quickly that it appeared to happen day-by day. Considering how little these fixtures were used, the change and rate of shift was somewhat alarming.


LR6 in Kitchen 2014. Note shift to green and pink in 2 of 4 units after just 2000 hours in service.

Now, anticipating there will be an argument made that the plastic glare shields I added have caused the issue, I tested the fixtures with and without the shields at 4 points within the fixture, including one at an LED in the array center using thermal probes, and found no difference with or without them, so am certain these had nothing to do with this issue.

Note also that the difference in image color is due to two factors. First, the original image was taken during the day (see the window), so there was a fair amount of daylight added to the space. Second, the camera used to take the first image has long been replaced. The second image was taken with the camera in my Samsung Note 3. This changes nothing in regard to the results being shown. The green and pink shift issue is very real. In testing the color performance of these fixtures, from the baseline of 2700K when new, the neutral fixtures were now 2750, the pink ranges from 2249 to 2399 depending on how long it is left on, the green is stable, but at 3350. The neutral fixtures were now 95CRI (92 CRIe / 94CQS), the pink 91CRI (90CRIe / 91CQS), and the green 87CRI (81CRIe / 89CQS), while the Du’v’ was as expected – the neutral was +.001 (anything under .002 is acceptable, the pink  -.0045 to -.0061, and green +.008, which, combined with the CCT shift, explains the movement from neutral to green and pink hues. In other words, the difference in color was not just subjective, it was measurable and significant, with the two shifted products falling well outside the ANSI bin standard for the 2700K CCT baseline. It was also interesting to note that after the neutral units had also shifted cooler, indicating they were likely on their way toward similar failure as the other obvious pair.  This was a disappointing outcome from a $275 investment and completely reverses my impression of this product from exceptional to unsatisfactory.

The shift from the black body line tells the whole story with the pink and green movement clearly visible.

The shift from the black body line tells the whole story with the pink and green movement clearly visible.


Overlay of the three colors shows how the original white light characteristic (the green line) is shifted both up and down to produce the pink variation (yellow line) and the green (red line).

The differences between the outputs is also clearly visible when compared against the 2700K standard center for the McAdams Ellipse, showing a variation well outside 3 steps, making it clearly, objectively verifiable as being a visible difference.

The differences between the outputs is also clearly visible when compared against the 2700K standard center to the McAdam ellipses, showing a variation well outside 3 steps, making it clearly, objectively verifiable as being a visible difference.

The Fix is In
Rather than replace these products with the newest version of the same – which to me has the same glare and brightness issue – regardless of the new lower price, I decided in stead to remove them and replace them with a more conventional PAR20 retrofit lamp from Philips. This allowed me to re-install the baffles in the downlights to create a proper appearance to the fixtures. I chose this as an opportunity to install new nickel silver baffles to fit the metalwork in the kitchen. The new lamps use 8W, instead of the 13W of the LR6, cost only $14, and produce more light on the surfaces I care about – the counter tops. Better still, the glare bombs are gone. While the end product efficacy is a bit lower due to the baffle absorbing some of the light, I just don’t care. I can now use the overhead lighting again. Hazah!

New Philips PAR20 LED lamps in new nickle baffles ends the glare, reduces offending brightness and reduced energy consumption by 45% - and eliminated the color shift issue.

New Philips PAR20 LED lamps installed with new nickel baffles ends the glare and offending brightness while reduced energy consumption by 45% – and eliminated the color shift issue.

Still Not Perfect
One issue remains, however. Dimming of the new “Dimmable” retrofit lamps remains pathetic. The new lamps only dim to about 50% of full brightness, using the newest Lutron wall box dimmer designed for dimming LED/CFL retrofit style products. However, at least don’t flicker while doing that, so I’ll live with it. The reduction in fixture brightness, coupled with dimming to whatever level they can deliver is a big improvement in both visual comfort and overall appearance in the space. Concerned that we were placing these lamps in a downlight, when the label for the product specifically states “not for fully enclosed fixtures” I checked operating temperatures and found that in the large, ventilated 6″ recessed can in an un-insulated space, their was no indication these lamps are under any stress. I am also not a fan of 2700K LED color, as it tends to look a bit artificially yellow-orange, but it is what it is.

Still Not a Fan of the Retrofit After all these Years
I remain solidly against retrofit solutions, as I believe they present compromises in performance and appearance, and apparently in reliability. Yes, I recognize it is the cheapest and easiest solution to deploying LED technology and saving energy. So are adding dimmers and automatic lighting controls, often for a lot less money.  While we spin our collective wheels selling ourselves short with cheap fixes, the actual potential and performance liabilities create reputation issues for the technology that will take years to overcome. The CFL died a PR death more than a technical death, LED retrofit products have the same potential for harm to the ultimate goal of integrating LEDs into the mainstream.

I’ve been using this kitchen as a test bed for applying retrofit solutions in a typical down-light condition. This is the last time we will apply this approach, as I am still unsatisfied that this is the best looking, or best performing solution. Now that down-lights can be found for under $100, with proper optics and external, truly dimmable drivers, my next round will be to do what I know to be the best solution – replace the fixtures completely and be done with it. For the meantime, I can now at least enjoy the kitchen lighting again.


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