watched the most excellent techtalk with
@Greengenes707 and
@Growmau5 today, (
http://tinyurl.com/techtalk5) and was thinking about their observations on applicability of certain chips depending on application current
their consensus was cree has an advantage at low current, and veros/citi/luminus had an advantage above 2A or so. This motivated me to get going on the sphere (new setup, identical active cooling on real heatsinks on all chips to give most accuracy esp at high currents. I figured out a way to slightly modify the heatsinks instead of attempting to cut the sphere. I plan on starting a new thread for just sphere data and discussion soon)
1216 vs. 1818gen6 vs. CXB3590DB (cree was fresh from cutter this week and is highest bin available in that color AFAIK)
View attachment 3921528
I thought the 1216 would do a little better TBH. about 3-4% less relative efficacy than the CXB in the usual 30-60W range. 1216 needs to be run at about 80% of the wattage of a CXB to have an equivalent efficacy (not bad for 50% of the price tho, if you can keep heatsink costs under control)
CXB with a very slight edge in efficacy (1-2% relatively) below 30W. Not as pronounced as i would anticipate.
1818 essentially equal to CXB from 30-50W where then 1818 pulls ahead above 50W
as we often see, chips are converging below 30W, the 1216 and 1818 are almost identical.
so this is congruent with GG's observations (though the crossover is probably shifted, he was probably talking gen5 citi and not sure which vero. I have gen7 V29 and will run soon on new setup. i expect vero C to be right there with 1818 and Vero B and D to be closer to CXB, just a guess)
Worth noting that CXB has the least dies of all of those chips (144). A testament to Cree's die quality for sure, and a solid performer esp at low current.
from here on out i will include spectra with my tests. raw data available in excel if somebody wants to get all QER with it. 1216 and 1818 similar as expected. CXB with an ever-so-slightly broader phosphor peak and the blue peak is a little lower than the citis