Quote Originally Posted by aaaaaaa
Hi Weeze,
I got some 5w 660s and a few blues from a while back, still haven't gotten around to making a light. The reason I ordered the 5w ones is because they are the most efficient, but now that I think more about it maybe I shouldve gotten the 15s. Much easier to deal with a couple 15wers than a whole bunch of 5s, much easier power supply wise too. So anyway how do they grow? You say its enough power, how many plants are you growing? Is 660nm really as good as its cracked up to be?
Depends on who does the cracking.

I have 2 45W arrays. One with 5s and one with 15s.
Both use 660 nm reds. They both grow great "Tomatoes".
2 large bushes per lamp about 4 sq. ft. ea..
Large, firm, juicy, stanky, "Tomatoes"
The 15s grow more on the lower branches seems to be the main difference.
I did get better penetration with the 5Ws when I added 30 degree lenses.
Once I factor in time, effort and include lens cost, the 15W leds look like the way to go.
Now I'm waiting for some bright company to start making 50-75-watt
660/470 nm. single substrate arrays bonded to a peltier junction with two leads, or even better wired to an E27.
(Don't want much, do I?)

I also have a 45W array of 5 Watters w/635nm. reds.
There I have a double blind that says.
Woo-freaking-hoo gimme two!
When the 660s come a shinin' through

The 632s work OK, but you need more wattage for similar results.
So, from personal experience, from a very small sample,
660nm. won, hands down!:thumbsup:

Aloha,
Weeze
Weezard Reviewed by Weezard on . Cree Xlamp Grow-Light Schematic Design (Wanted) Been sifting through the cruft trying to find a schematic to build a grow lamp, using Xlamp LED's from Cree. Their time is now :) Yes I've seen the extraordinarily overpriced products being offered by businesses. Not worth the money if you can use a soldering kit, imo. I can solder, but I'm no engineer, so, I'm asking for help in creating a circuit design that balances low cost, simplicity of construction and high efficiency. Preferably with 120vac input (off the shelf ac-dc Rating: 5