@GroErr How many watts would your optimal COB setup draw to cover a 4x4 tent? I wish there was a comprehensive guide with parts list.
I'm not the guy to ask as I'm trying a build for the first time but there are certainly enough more knowledgeable folks in here that can chime in on your questions.
The coverage question is a good one I'd like to see some opinions on. It depends I think, many are driving these COB's at lower amps which gains efficiency at the cost of wattage output but higher efficiency. So for example if you built 400W running them @700ma, my understanding is each COB would put out approx. 25W (16 COB's) but at higher efficiency and run cooler so should provide longer life. Would that provide greater coverage or simply efficiency/life than say 8 COB's @1400 ma?
If they were my only lights and I was trying cover a 4x4 I'd tend to go with 500-600W. Question would be say 500W being driven @700ma perform/produce better than 600W being driven @1400 ma? Or being so efficient, would 400W being driven @700ma cover this area well?
The parts list also depends on a few factors like my comments/questions above and everyone's designs have variations that can change the parts involved. e.g. Whether you'll be active or passively cooling them has variables. The most common seems to be active cooling using CPU heat sinks and CPU cooling fans. This is likely the lowest cost as the CPU heat sinks & fans can be purchased relatively cheap. But with active cooling you're now having to also power those fans, so you're into more parts and operational cost/overhead for powering those fans.
I'm going to try passively cooling them with big-ass heat sinks. This drove my up-front cost higher but I don't have to deal with active cooling components. Just a preference I have and want to attempt. It comes from dealing with computer CPU fans and power supplies over the years and seeing many of them fail. I didn't want to depend on, power, or monitor a bunch of small CPU fans so I over-enginneered (and paid for!) on the heat sinks to reduce the complexity and dependence on CPU coolers. I likely won't save anything on operational costs for cooling as I expect I'll have to blow some air across them but if needed I can use a larger (or a couple), more reliable fan(s) to do that which is easier than keeping an eye on a bunch of small CPU fans. I'd be Ok with that as it would remove the risk of a failed CPU fan causing COB failures/overheating.
Haven't built them so too early to post a detailed build/parts list but once I settle on the final design and build them I'll post a build including a parts list.
