The main specs by the manufacturer:
–4000K color temperature (also available in 2200, 2700, 3200, 5000 and 5600K)
-CRI (Ra) 99
-A single SmartEcoLighting SOL COB LED
–9W power rating
-AC voltage of 220/230V (also available in 110/120V and 3-35V DC)
-Couple of options for reflector and lens instead of diffuser
See also my previous review of a bulb from SunLikeLamp.com which features four of the different color temperature COB LEDs:
Review SunLike10xss SOL Ultra High CRI E27 LED bulb (2700/3200/5000/5600K)
Measurements were made in a 50cm integrating sphere with an x-rite i1pro spectrometer after the bulb had warmed up for 1 hour. Intensity (lux at 1 meter, candela) was measured outside the sphere at 50cm.
The bulb was connected to mains power which at the time of testing was at 230V.
Power consumption at the time of measuring the CRI parameters was 9 watts at 230 volts with a low power factor of 0.57. Total bulb efficacy is low but understandably so for an ultra high CRI light source at 73 lumens per watt. Remember that this bulb sacrifices efficiency for the ultimate spectrum.
Output at 1 hour is 631 lumens. The output drops just 5% during the first hour from 665 lumens at turn on. This is a sign of good heatsinking, which is also evident by just looking at the bulb.
Light output in lumens was plotted over one hour. Output is stable after the intial warmup.
Maximum output is reached immediately (90% in 0.6ms)
The CRI data was measured integrated after a 1 hour warmup in an integrating sphere.
Color rendering is practically ideal as seen from the smooth spectral power distribution (red line tracks the blue reference almost perfectly). CRI Ra of 99 and R9 of 99 and TM-30-18 fidelity index Rf of 98 and gamut index Rg of 100 are excellent. The phosphor mix manages to practically remove any bumps from the spectrum. There’s no near UV content.
Visually the light is neutral white with excellent saturation to all the colors it illuminates.
Load IES TM-30-18 Color Rendition Reports by clicking the thumbnails:
CGATS CRI Data file:
Color temperature and tint
Tint is right on the black body line. Remember that when LEDs heat up, their duv value almost always decreases and becomes less green/yellow. This was measured after 1 hour in an integrating sphere.
Tint is very even around the bulb thanks to the heavily diffused bulb.
The switching frequency of of 90kHz with its minuscule modulation is not visible to the eye or to cameras. The snob index of 0% guarantees that it’s easy on the eyes.
AC power draw
Current is drawn in short pulses 100 times a second as the input voltage gets high. There’s no power factor correction which results in a power factor of about 0.6.
Cyan line: mains line voltage
Yellow line: current draw of the bulb
Violet line: power draw (voltage * current)
Just like the multi COB lamp from SunLikeLamp I tested earlier, this neutral ultra high CRI bulb produces the smoothest spectrum of light out of all LED sources I’ve tested. The Chinese SOL COB LED emulates a black body radiator almost perfectly and also looks gorgeous. The light is flicker free and very stable in output thanks to the good heatsink and good driver. For under $20 I can’t think of a better bulb to get.
Please note that the test was done when the bulb was brand new. I can’t guarantee that they will perform similarly after months or years of use.