Cree 4Flow LED (2015) review: Cree's new and improved 4Flow LED doesn't dim as well as before

The newly refined Cree 4Flow LED boasts better specs, a longer warranty, and the same $8 price. But is it actually better than the old one?

Ry Crist

Ry Crist

Senior Editor / Reviews - Appliances

Originally hailing from Troy, Ohio, Ry Crist is a text-based adventure connoisseur, a lover of terrible movies and an enthusiastic yet mediocre cook. A CNET editor since 2013, Ry's beats include smart home tech, lighting, appliances, and home networking.

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Cheaper isn't necessarily better. That's Cree's message in a year where LED prices are plummeting, and where new arrivals from Philips and GE can be had for less than $5 each -- an eyebrow-raising comparison to the $8 Cree 4Flow LED , which sits right next to them on Home Depot shelves. You get what you pay for, Cree warns -- those cheaper competitors aren't dimmable, and they don't last nearly as long as the 4Flow LED, either.


Cree 4Flow LED (2015)

The Good

The new Cree 4Flow LED will last almost five years longer than the original, and Cree backs that claim up with a longer warranty than before. Efficiency and color quality both get slight upticks, too.

The Bad

The new 4Flow didn't perform as flawlessly in our dimming tests as the original.

The Bottom Line

The 4Flow's convection-based design is terrific, but the new model isn't as as much of a slam dunk for dimmer switches as its predecessor.

It's a solid argument, and one that's helped Cree carve out a reasonable middle-ground price point that, for many bulb-buyers, is likely worth the extra couple of bucks. Now, less than a year after the 4Flow's debut, Cree's seeking to strengthen its claim by refining the 4Flow's hardware and replacing it with a new-and-improved model that'll sell for the same $8.

Among the improvements are small steps forward in the bulb's efficiency, its lifespan, and in the warranty, which Cree is raising from three years to five. Unfortunately, there are some disappointing steps backward, too. Despite having the same lumen listing as before, the new 4Flow came in a few percentage points dimmer than the original. It also isn't nearly as good on certain dimmer switches, with a constant flicker at minimum settings that we didn't experience the last time around. The new 4Flow LED is still a decent bulb, but it's not as flawless as before, and not as easy to recommend over those cheaper competitors.

Cree gives the 4Flow LED a tune-up (pictures)

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The new 4Flow LED looks exactly like the original -- the only way to tell the two apart is to read the fine print on the base of the bulb. There, you'll see that the original is listed at 11 watts. The new 4Flow rings in at 9.8 watts, yet claims to put out the same amount of light (815 lumens), making it the slightly more efficient option.

I really can't fault Cree for leaving the design as-is -- it's a good-looking bulb that perfectly mimics the shape and silhouette of an incandescent. Turn it on, and it's difficult to tell that it isn't an incandescent.

Enlarge Image
Tyler Lizenby/CNET

The trick is in the heat sinks -- or rather, the lack of them. The Cree 4Flow manages heat with convection vents in the top and bottom of the bulb, instead. No matter which direction the bulb is oriented, there's always an opening above and below the heat-producing hardware at its core. Thanks to thermodynamics, the hotter air vents out while cooler air vents in -- hence "4Flow," and hence the reason why this bulb doesn't need bulky heat sinks bogging it down.

Like the original 4Flow LED , the new version puts it light out at a yellowy color temperature of 2,700 K, or a whitish 5,000 K if you're willing to spend an extra buck. Cree claims that they've improved the bulb's color rendering score, which measures how accurately it illuminates different tones. The original scored a very average 80 out of 100 -- the new one comes in at 83. It's a pretty minuscule bump -- you really need to get up over 85 before you'll start noticing colors that look any more vivid.

Cree vs. the Competition

Cree 4Flow LED (2015)Cree 4Flow LED (2014)Philips SlimStyle LEDGE Bright Stik LEDPhilips 60W Replacement LED
Lumens (measured / stated) 777 / 815835 / 815815 / 800786 / 760821 / 800
Watts 101110.5108.5
Efficiency in lumens per watt (measured / stated) 78 / 8276 / 747879 / 7697 / 94
Yearly energy cost (3 hr. per day @ .11 kWh) $1.20 $1.32 $1.26 $1.20 $1.02
Color temperature (measured / stated) 2,619 K / 2,700 K2,617 K / 2,700 K2,653 K / 2,700 K2,830 K / 2,850 K2,701 K / 2,700 K
Other color temperatures (price difference) 5,000 K (+$1)5,000 K (+$1)5,000 K (+$1)5,000 (+$1)5,000 K (+$0)
Color rendering index 8380808180
Dimmable range 6.1 - 100%5.6 - 100%11.1 - 100%Non-dimmableNon-dimmable
Dimmer switch flicker/buzz LightNoneModerateN/AN/A
Lifespan 30,000 hours (27 years)25,000 hours (22.7 years)25,000 hours (22.7 years)15,000 hours (13.7 years)11,000 hours (10 years)
Weight 1.90 oz.1.90 oz.2.20 oz.1.60 oz.1.80 oz.
Energy Star certification YesYesYesNoNo
Warranty 5 years3 years3 years5 years3 years
Price $8 $8 $9 $10 (3-pack)$5

The other improvements are even more unseen: a longer lifespan and a longer warranty to go with it. The original 4Flow promised to last 25,000 hours -- 22.7 years, if you use the light for three hours a day on average, with the first three of those years covered by the warranty. The new model bumps that up to 30,000 hours, or just over 27 years, with a five-year warranty. I'm not sure that anybody felt that 25,000 hours just wasn't enough, but it's certainly a good slap in the face to the less expensive Philips 60W Replacement and GE Bright Stik LEDs, which claim lifespans of 11,000 and 15,000 hours, respectively.

Cree's 4Flow LED is compatible with most dimmer switches -- a key leg up over the non-dimmable Philips and GE LEDs. Cree claims that the new version is compatible with even more switches, and that it won't buzz when you dim it, either. Sure enough, I didn't hear any buzz as I dialed it down (same as with the original), but I did notice a fair amount of flicker at low settings, which was new. To keep things fair, I dug the original bulb out of storage and re-tested it -- it still dimmed like a champ, with little to no flicker whatsoever. On the exact same switch at the exact same setting, the new version flickered badly.

In fairness, the flicker only occurred with one out of three of the dimmer switches on our rig, an admittedly small sample size. Still, it's a very common model: a Leviton switch designed for use with LED bulbs, and one that sells just steps away from the Cree section at Home Depot. Your mileage may vary based on what switch you're using (and on other factors, like voltage irregularities), but for what it's worth, the old 4Flow aced our dimming test while the new one did not.

Something else I noticed: the new 4Flow didn't test quite as bright as the old one. Both are listed at 815 lumens, but while the old model came in high at 835, the new model came in low at 777. It's a relatively small difference, and not one that you're likely to notice with the naked eye (I couldn't), but if you're a stickler for brightness, you'll want to take note. Just keep in mind that both numbers sit within our integrating sphere's 5% margin of error, if only just barely.

Tyler Lizenby/CNET

The verdict

Is this a better 4Flow LED? That's a tougher question than it ought to be. On paper, the answer is yes. It's more efficient, with approximately the same light output as before from a lower power draw, and it boasts a better color rendering score, too. On the other hand, it didn't fare as well in our dimming tests, and it didn't register quite as much brightness as before, either.

Both of these qualms -- a new flicker on one dimmer switch and a lower lumen output -- are pretty nit-picky, and neither one is enough for me to call the new bulb a categorical step back from the first. The longer lifespan is a welcome, though perhaps unnecessary, improvement, and the longer warranty will appeal to many, as well. But superior light quality is Cree's eight-dollar claim here, and flawless dimmability was the original 4Flow's trump card against its cheaper competitors. The new model can't play that card as effectively as before. This is still a decent light bulb with a clever design, but it's not the clear slam dunk that we've seen from Cree bulbs in the past.


Cree 4Flow LED (2015)

Score Breakdown

Design 9Value 6Performance 7