There’s only 119 days to get your holiday Christmas lighting planned, purchased and installed. With tree lights, interior décor lights as well as innumerable outdoor lighting opportunities, you want to make sure your string and replacement bulb supply can handle any creative impulse.
For baby boomer traditionalists, who remember Christmas lights from their childhood, the C7 and C9 type bulbs shine bright in our memories. Whether on the tree or outlining the house, these bulbs didn’t just produce points of light like many small format holiday lights today. They illuminated a large bulb surface area that produced a bold array of festive light.
Today, you can still buy both C7 and C9 incandescent individual replacement bulbs or strings. You also have the option of LED C7 and C9 in both single bulbs and strings.
The LED option offers both significantly lower energy costs and much longer life than incandescent. However, before you scoop up an arm full of LED C7 and C9 strings or bulbs, it’s important to understand how to shop for them, especially if you want them to replicate the brightness of the traditional incandescent.
The table below shows C7 and C9 incandescent watts-per-bulb compared to two different LED options on the market.
C7 Incandescent = 5W
(Brand 1) C7 LED = 0.37W (3 diodes per bulb)
(Brand 2) C7 LED = 0.96W (3 diodes per bulb)
C9 Incandescent = 7W
(Brand 1) C9 LED = 0.45W (5 diodes per bulb)
(Brand 2) C9 LED = 0.96W (5 diodes per bulb)
To get a brightness level comparable to an incandescent C7 or C9 you need to purchase LEDs with a watts-per-bulb of at least 0.96 watts. Brand 2 above meets this requirement.
It’s possible you like the C7 or C9 shape but don’t need the high brightness level. Brand 1 in the table gives you softer illumination plus a traditional bulb shape.
The important point to remember: there can be a big difference between brands in watts-per-bulb for the same shape bulb. Look closely at the specifications to make sure you know what you are buying.
You can also see in the table above that number of diodes does not necessarily indicate the same wattage. It all depends on the types of LED diodes being used by the manufacturer.
It’s interesting to note that the Brand 2 LED option for both C7 and C9 are rated at the same 0.96 watts. The 7/8” diameter (C7) and 1-1/8” diameter (C9) provide way more space than required for LEDs. The brightness of the C7 and C9 is not constrained by bulb size, so it’s possible for both to have the same light output. In fact, much smaller LED bulb sizes can produce brightness levels higher than either C7 or C9.
If you can’t resist the nostalgia for the Christmas lighting of 40 to 50 years ago, you can still enjoy it with C7 and C9 bulbs driven by energy efficient, long lived and very 21st century LEDs.
Shop for Christmas Light Bulbs Now
featured image © Thomas / Flickr Commercial License
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