Re: better choice
Re: better choice
<a href=showthread.php?s=&postid=15308769#post15308769 target=_blank>Originally posted</a> by tahiriqbal
Much better choice and cheap too.....
http://www.dealextreme.com/details.dx/sku.15943
IMHO, "much better choice" depends strongly on your selection criteria. The Rebel and the XR-E (in their highest available bins, 100 and Q5 respectively) are about the same efficiency, ~90 lumens/watt peak (350mA drive current). They decay about the same, so at the currents we seem bent on running them, 700 - 1000mA, again they are about the same in terms of output.
The obvious difference is package. The Rebel is TINY compared to the XR-E, which means you can fit three on the same small star. If you need to get a ton of light over your tank, or have a weird packaging constraint, the Rebel is a clear choice. And, since the Rebel has a slightly wider viewing angle, three of them mounted on the same star should have similar coverage as three individual XR-E mounted a few inches apart. And, since they are three on a star, that means 2/3 less mounting and soldering work!
Price is a wash, depending on how you buy them. The 3-up Rebels are about $16-$17 from ledsupply.com, or a bit over $5 per emitter. So the same as buying XR-E's from DX.
Of course, the 1-up Rebel stars are expensive, so if you somehow don't want the 3-up version and really want 1-up stars, the XR-E is a better choice.
The Rebels also have a slightly lower forward voltage. If you read through the thread, some people people have been getting nervous about running 6 XR-E's on a buckpuck at higher currents, since that adds up to a fraction of a volt more than you "should" have if you are using a 24v supply. The Rebels are a few tenths of a volt less drop, so you won't hit this problem.
FWIW, I'm using both on my nano build (ledsupply.com order arrived over the weekend!) Just need to get cracking on the drivers. . .