High End COBs vs $2 COBs...

muleface

Well-Known Member
I have about a year under me for growing, I have grown under cheap LEDs, Vero 29 cobs, T5s, and Q-boards.

My question is about COBs; really does it matter if they are $2 ebay COBs or $50 Cree 3590's?

Removing the obvious quality difference of the end product, I would assume someone put more time and love into manufacturing a CREE COB, but the end result is really more important thing. If I'm running 50 cobs, we are really talking about a lot of money in cobs, 2.5k in cobs alone. If i went with some cheap ebay cobs, i could get 100 of them for maybe $150, and each time one burns out, toss it, or replace all of them each grow.

What is the practical life of a cree COB? 2 years?

does the end harvest really suffer $2350 in crop loss?

is there an electrical cost that could help mitigate the higher cost of the COBs?

I am really looking for some hard answers here, not a "you get why you pay for" or "i only run CREE" something quantifiable like...

you would need 3 ebay cobs running at 80 watts to get the same light output as 1 cree running at 80 watts, or statistically ebay cobs have a 20% chance of burning down your house.

thanks!
 

CobKits

Well-Known Member
My question is about COBs; really does it matter if they are $2 ebay COBs or $50 Cree 3590's?
no

$12-$15 cobs outperform $35 cxb3590s

there are prob some really good cobs out there under $10 if you start digging

What is the practical life of a cree COB? 2 years?
most any cob at the currents we run them at will go 20 years. they may not be the most efficient but if your ebay cobs last 6 mos they'll prob go 10 or more years
 

Sureshot2

Well-Known Member
I have a few cheap ebay cobs in my clone tent that I have had no issues with for almost six months now. At any given wattage they definitely output less than my citizens, but considering each one including heatsink was less than the cost of one citi 1212 I have no issues using them as an addition to my t5 in the clone tent. That said, I would never consider using them in my actual flower tent due to the lower efficiency and possible questionable reliability - I would rather not gamble on reliability where it matters the most. Just my 2c, ymmv.
 

muleface

Well-Known Member
I would like to see a sub $10 dollar cob that can play in the same park as Vero, Citizen or Luminus. Anyone know of any? I would think if we are using l/w as a benchmark, then something around 140-160l/w would be sufficient. That seems to be the range of most high end cobs. Plus if you picked them up at 5-10 a cob, you could swap them out after a few years when tech drive up the l/w factor.

What else would we look at? I would agree that if the cob lasted 6 months, it will probably last 10 years.
 

CobKits

Well-Known Member
Plus if you picked them up at 5-10 a cob, you could swap them out after a few years when tech drive up the l/w factor.
thats why the $10-$12 clu048-1212 are the bomb. youre already set up for a quick upgrade on the popular 28mm chip size. like when gen4 luminus cxm22 come out next year or so
 

VegasWinner

Well-Known Member
I have about a year under me for growing, I have grown under cheap LEDs, Vero 29 cobs, T5s, and Q-boards.

My question is about COBs; really does it matter if they are $2 ebay COBs or $50 Cree 3590's?

Removing the obvious quality difference of the end product, I would assume someone put more time and love into manufacturing a CREE COB, but the end result is really more important thing. If I'm running 50 cobs, we are really talking about a lot of money in cobs, 2.5k in cobs alone. If i went with some cheap ebay cobs, i could get 100 of them for maybe $150, and each time one burns out, toss it, or replace all of them each grow.

What is the practical life of a cree COB? 2 years?

does the end harvest really suffer $2350 in crop loss?

is there an electrical cost that could help mitigate the higher cost of the COBs?

I am really looking for some hard answers here, not a "you get why you pay for" or "i only run CREE" something quantifiable like...

you would need 3 ebay cobs running at 80 watts to get the same light output as 1 cree running at 80 watts, or statistically ebay cobs have a 20% chance of burning down your house.

thanks!
Why not mix them? there is no reason to pick one true course. There is more to it than picking one side or the other. I use cheap full spectrum cobs, cree cxa's cxb's xre's and inexpensive far red and deep red cobs, as well. The plants do not know the difference between cree, Vero, or inexpensive COB's. As long as they work as advertised, I am getting my money's worth. Plants are a lot happier when I make choices for them instead of choosing brand names, like most things folks are guilty of. I say put down the brand name kool-aide and try some of your own experiments.

I have found with full spectrum cobs from ebay made in China like cree and vero, the plants love the light. I use these in my home garden and the plants are much healthier than past with just cob white lights.

The argument was Cheap Chinese diodes, now we know 90% of all diodes are made in China. They have the Quality Control (QC) process called binning. In this process the diodes are rated and the best are bought for the most and the worst are sold for the lowest like beef and pork in America, all the same just different outcomes based on human workers running equipment and overseeing the QC,. Most diodes are probably made in one or two factories, not like in America, where capitalism reins, Communism trumps capitalism and I am sure they share space.

So long story short, experimenting is cheap. try some and let us know your results.
namaste
 

VegasWinner

Well-Known Member
I have a few cheap ebay cobs in my clone tent that I have had no issues with for almost six months now. At any given wattage they definitely output less than my citizens, but considering each one including heatsink was less than the cost of one citi 1212 I have no issues using them as an addition to my t5 in the clone tent. That said, I would never consider using them in my actual flower tent due to the lower efficiency and possible questionable reliability - I would rather not gamble on reliability where it matters the most. Just my 2c, ymmv.
I use a 50w full spectrum for cloning and the clones are healthier than ever before. i used to use other lights, but I am now sold on the spectrum being healthy for plants, better roots, better color clones, etc.
 

nachooo

Well-Known Member
I used similar full spectrum chinese chips ...they were not epistar chips, I choosed the bridgelux chip (aparently much better).and sprouted seed under them... initially plants were health and happy but soon they started to strech a lot, in vegetative phase.
I had a control room at the same time with a mix of white cree diodes and old 630 nm red 1 watt leds (and old led bar from 6 years ago) that gave me much better results with the same batch of seeds. The internode was half the space in the last case.
 

Goerilla

Member
I have a few Chinese cobs and one lamp I made is with 2 100W driven at 50W.
Now I made another lamp with the same size driver but one Citizen 1212 3500 90 cri instead.
It seems that the one Citizen produce the same amount of light as the 2 Chinese combined, that´s with half the power.
No more Chinese for me but it was fun trying them out and when I started building lamps there were no semi cheap quality cobs on the marked.

Rilla.
 

nachooo

Well-Known Member
100 watts of cheap chinese led with luck,100 lumens per watt : about 5 dollars per led...final product about 100 gr
100 watts of a good vero, citizen etc.. around 150 or more lumens per watt : about 25 dollars per led final product about 150 gr
Cheap leds give much more heat than the good ones also....so more money to manage the heat..heatsinks, airflow etc...
A good chip get paid itself and more in one crop
 
Last edited:

muleface

Well-Known Member
I have a few Chinese cobs and one lamp I made is with 2 100W driven at 50W.
Now I made another lamp with the same size driver but one Citizen 1212 3500 90 cri instead.
It seems that the one Citizen produce the same amount of light as the 2 Chinese combined, that´s with half the power.
No more Chinese for me but it was fun trying them out and when I started building lamps there were no semi cheap quality cobs on the marked.

Rilla.
so 2 - 100 watt cobs (running at 50 watts each) gave the same light as 1 citizen cob running at 50 watts? the 100 watt cobs must have been really crappy. that's half the efficiency, but i can see that...

100 watts of cheap chinese led with luck,100 lumens per watt : about 5 dollars per led...final product about 100 gr
100 watts of a good vero, citizen etc.. around 150 or more lumens per watt : about 25 dollars per led final product about 150 gr
Cheap leds give much more heat than the good ones also....so more money to manage the heat..heatsinks, airflow etc...
A good chip get paid itself and more in one crop
so would you say that would make Cree chips better then Vero as they are twice the price?
 
Top