Opinions on COB vs QB LEDs

This somewhat of a true statement. I’m not sure the differences in efficacy, but they do cost more because a proper sized heat sink is required. No fan dissipate heat, all passive cooling, but they do have excellent canopy penetration. Once you find the correct height, I’ve pretty much left them alone.

Rapid LED kit shown above, and they send everything you need except wire. Which I think they’ve changed a bit and send wire now. There’s 817 possible watts, and I can run them around the 400W total and its plenty for flowering. I ran the grow really hard at all 800w and I got a lot of yellowing. So I’ll be dialing back next round. Been growing for about 5 years now, and these light continue to produce.

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Generally speaking, the mid power pcb style lights (quantum boards) will have a higher ppf per watt than chip on board styled leds. The pcb styled lights are also usually a little cheaper to put together as well. When using higher end cobs it’s definitely possible to get close to mid power performance though. I agree that one reason for cost is heavier heatsink requirement due to condensed thermal load of the cobs.

I think you can diy with either fairly easily. Most would probably prefer using boards or strips of the mid power leds due to the increase in efficiency. But if you’re resourceful enough you could probably build out either at a reason price.

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Those kits from Rapid look very interesting. They use the cree chips and everything which is a great selling point. Like you said I really appreciate the canopy penetration of my cobs the ones I have are cheaper ones and actually have fans built in over each heat sink to so if I can actually manage to build one like those without the fan that would save me a bit as well. I was looking at the kits from Rapid and it almost looks like I could get all the pieces needed for a kit separately to try to keep the price down without paying for the name brand kits? Would the only drawback to this be that it might be a bit harder to put together and I’d loose the customer service from those companies? Or is there a step that I am missing as someone who has never attempted one of these projects before? All this info with the tuning of the lights from 800 to 400 and everything is pretty much exactly what I was talking about when I was saying I needed opinions on peoples experiences on these lights and why they do what they do. I feel like we all grow better together when we can figure out all the little missteps and great successes we might have all made along the way and just figure out how we can all get the best out of our hobbies. thanks for the input

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I feel like I’m already learning so much more about both types of these lights. You all are helpin out so much thanks. Do you think the mid range pcb lights are comparable to the cob lights that you might be able to build with the cree cobs for the same or comparable price? Knowing that I’ll hopefully be able to diy either of them really opens up the options for my next light because that will almost certainly be cheaper. As far as the diy pcb lights do you recommend the hlg 260 xl or is there another that you think is a good comparable light?

What kind of strips do you recommend if I can get those in the future? I hear a lot of people talking about cutter strips and I think that you can just attach those to a heatsink as well but like I said I am a novice in terms of building lights I’ve always bought them pre-built which is just getting to expensive for me. I think that now I might be at the point I can tackle that kind of project though. (hopefully haha)

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I assure I’m you I priced everything out individually, and it comes out more.
Secondly, I want top bin chips, not questionable where they came from.

Some of this is my fault. Each grow I tried pushing the plants as hard as I could.

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That is so good to know that someone already tried to price out everything individually. I totally agree I think the chips make a huge difference with the cob lights in terms of how the end product works out. And yea I totally understand trying to find out how hard you can push the plants. I just had the same problem in my veg closet where the light I switched to is a bit to bright and causing some light stress so I’m trying to work that out. But hey that is how we get the strongest healthiest girls possible you know trial and error and then learning from each other.

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Cutter has good stuff. Pacific light concepts, chilled tech, horticulture lighting group, and many others all offer diy pcb’s. I have a thread on here that I did one with bridgelux eb series. Others have put up topics with multiple Samsung strips as well.

Sometimes it’s just a matter of what you can get into for best price at the time. The cxb3590 was the top dog when diy game started getting big. Since there are multiple newer cobs that perform better and are even cheaper. If you decide to go cob route, check out the bridgelux vero 29b and 29c. Also the Luminous cxm22. You can generally find all of them in +/-$20 range, and they are all as good or better than whats typically available in the cxb.

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This is all such good information. Especially for somebody just starting into diy like me. Having all these starting points and everything and getting opinions from other experienced growers is so much help. I’ve already been following one of the diy threads that you did so I’ll have to go back and find that one to because I’m very excited about the possibilities of doing diy lights to try to increase what I have in my tent and closet. Between this thread and a few others that I’ve been reading through on here I really feel like its so much more of a possibility than when I first started looking into it.

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It’s right here

Keep in mind It’s a small light and was designed to be a budget build a while back.

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Thanks so much man. I’m goin through that right now and its so full of exactly the kind of stuff I need to know to be able to build one of these well and without spending to much. Kinda feel like I’m goin down the diy rabbit hole now haha but this way is going to make it so I can get so much more light affordably and in a customizable way to which is exactly what plants need to grow the best.

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Thanks to @dbrn32 and the thread you sent me and a few others that you have that I’ve been reading through as well as some more research I did I was able to figure out that the light I have in my closet right now already has an adjustable driver and figured out how to dim that a bit to hopefully help the light stress on my smaller girls and clones in my closet which is awesome.
I also have been getting a lot more comfortable taking my lights in and out of my tent to adjust them and everything thanks to doing that more and got up the courage to try to clean them even more than the usual just canned air through the casing holes. I ended up taking each light out of the tent one at a time

(incase anyone wants an idea of what kind of light I’m working with/talking about) and taking the casing apart by taking the 4 screws out of the sides of the cases… and then cleaning the inside fans and heatsinks with a small brush and the canned air very gently to try to keep the lifespan of these lights going as good as possible. I think it will end up making a bit of a difference as the inside of the case was much dirtier than I could get without opening it up. This is the fans and the heatsinks in one of the lights when I first opened it up even after trying to clean through the slits in the casing with the canned air…
Now after I cleaned the fan blades with a small brush each individually and then cleaned the heatsink. I had to keep cleaning the brush because of how dirty the fan blades were but they look better now.
Honestly this is my first time actually opening up the cases on any lights and I wouldn’t have felt comfortable doing it without reading a ton of the DIY threads on here and I can’t recommend that anyone do it willy nilly as there is always a chance that you can mess something up very easily. (Especially like me your fine motor skills get worse the more things that you do sort of bent over and doing very precise things. I have lots of back issues) But I think that doing this every once in awhile will probably help the lifespan of my lights where unlike the normal DIY lights I can’t just clean the heatsinks etc…
Do others with lights in cases take the cases apart to clean the insides or is just using canned air usually good enough? I like trying to be able to get the full lifespan out of everything that I’m using by being as proactive with it as I can. I’m just very inexperienced with the electronic side of everything… (usually more just going along and willing to take things like lights at face value but this is bringing me down the DIY rabbit hole and gunna save me a bunch I think)
Thanks to everyone whose been helping so far. In this thread and in all the others that I was reading this place is an endless well of great info.

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@dbrn32 sorry to keep buggin you man but I was reading a comment you posted in your “Lets talk DIY lights thread” that you had posted a few years ago (it takes me awhile to absorb all the great info in these threads in a way that I can actually use it haha) but in the comment you said that you maybe have removed drivers from lights like the ones that I posted above and relocated them outside of the tent to try to mitigate the heat from them? Would that be a possibility with these lights as well? Also along that idea where I’m already looking into doing a DIY build very soon if I do plan to relocate those drivers outside the tent would it be a decent idea to try to upgrade the drivers for just the LEDs of the lights not the fans to one that can be dimmed and run more than one light at a time? I honestly don’t know fully the possibilities that are there when it comes to this but it seems like such a good idea to at least be able to regulate the heat better even if upgrading the drivers for these lights isn’t a possibility right now this project will give me some very basic experience on my way to building my whole light…
Again sorry to keep buggin you man but you seem to just be able to break down all of this in such an easily digestible way so I hope you don’t mind helpin out

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Sure. You just need to extend the wiring in and out of driver to reach the fixture from wherever you want to place driver. If it’s more than a few feet you may want to look at going up a size in wire for voltage drop. Then just make sure the wire you use is rated for driver load.

This is probably not worth the cost, but if the led module voltage cooperates you could probably do it.

If you have light related questions I’m always happy to try and answer. Most of thd time if you were going to modify an Amazon light it would be to just upgrade the led modules. I’m not sure which citizen leds are in your lights, but they may be pretty solid leds already. Which would limit the amount of gain you would have by upgrading. Imo if you’re going to start spending money, may be better to just build from scratch.

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Thanks so much. I can’t tell you how much getting solid feedback from people with experience means to me. That really is how we all learn the best. I’m thinking that moving the drivers outside of the cases is a good idea I will wait on the upgrading of them because of the feedback and I’ll put that money into the building of a solid light to really fill up my space. I’m starting to be able to wrap my head around all of this so much more based off of all the conversations in the threads that you have and everything so thanks so much again people like you and other experienced and those learning and sharing what they know are what make this forum such a great place for everyone to get together and learn everything.

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Anytime my dude!

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So @dbrn32 This is actually the light that is flickering in my tent right now. You can somewhat see the driver in the picture here. My question about this light is if both leds are coming on when it flicks on (so I don’t think it’s a problem with the led’s) and it turns on when you turn the light off then on again would it be a problem with the driver or possibly loose wiring that I could try to fix where I’m starting to do some diy stuff? Would it be worth replacing the driver if its a problem with the driver on a light like this? I can try to take the light again later today or tomorrow at some point to get a better picture of the driver if that helps to. As always thanks for any help man.

Make sure I understand this correctly…

When you turn the switch off all leds are on. When you turn the switch on the leds go off, but then come back on?

What happens then? Is it rapid and indefinite flickering, or the light just goes out for a second every now and then?

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Sorry for the confusion man. I’m workin on the light today. When its on and the lights are actually on both lights are on. But they somewhat quickly will both turn off usually. If I flick the switch off then back on the lights tend to turn back on for a bit then turn back off. They also seem to stay on if I hold/pinch where the switch is on the frame with power on so I’m leaning towards a bad connection at the switch if you think that sounds at all possible? The switch does seem to be alittle loose in the frame. I also just realized this light for some weird reason has one driver for each LED and one driver for each fan so there seem to be 4 small drivers in this 1 little light for some reason. I’ll try to take a good picture of the LED driver just cause why not.

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Makes perfect sense. The leds and drivers are usually good or not, as in not a lot of in-between. The situation you are explaining sounds like a bad connection or maybe even a flaky switch. You could probably bypass the switch if using a timer to turn light on and off.

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Just a quick update… Got the light working. At least for now. Seems like it was a problem with the switch. Only one side actually was working when I hooked up a multimeter to it so I had to find a way to join the wires together without that portion to kind of go around the bad part until I get another switch. Thanks for the feedback man it was right on point. I’m so looking forward to getting into putting that new light together now and really jumpin into the DIY stuff.

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