who is buying me a XP-E2 Torch led? Update: DBCstm did, test is in post#81

I can send you 6 djozz and that will free up 4 for another member.

The cost was $1.72 apiece, I will be checking on (and sending out some) small bubble envelopes at the Post Office today. It looks like that will be between $2 and $4. I’ll be sending some to the in Finland so that will give me an idea of the package cost and shipping. The ones going to the land down under are getting a free ride along with something else. lol

Thanks djozz! Some English phrases still does not compute in my danish grey matter :-)

If shipping is between $2 and $4 I would still like four -if you still got some

I had a fine education in slang because I lived with in one house for half a year with two irish guys (one catholic from Dublin, one protestant from Belfast, true story!), with a good amount of guessing from my side the communication went along fine. Works for Irish and works for Texans just as well :bigsmile:

LOL! Sounds like an explosive clash of religion and accents :-)

I once took a 3d animation class in Denmark. But most the teachers were foreigners. German, French, American (Texas) and Finland.

One of the danish students of the course once lived in Ireland for 2 years. His English accent was HILARIOUS!

Imagine English language with a thick danish accent - while trying to sound Irish. For some reason he thought a lot of cursing made him sound more Irish :-D

He had a lot of arguments with the teacher from Texas. Those were sooooooo fun to observe!!!

Really bad english with thick danish accent :-)

oh oh oh. And we had a danish teacher (a class on how to do clay modelling) who had to speak English because of the mixed student nationalities.

His wife was nude posing for our clay modelling. And the teacher kept saying to one of the french students that her claymodel had to be more filthy. It was sooooo weird, innapropriate - and fun.

What he actually meant was voluminous. In Danish voluminous is fyldig - and he thought fyldig translated into filthy


- Sorry for the off topic

It was late last night, but I dedomed an XP-E2 torch and stuck it in a cheap zoomie light (sorry, no crash testing yet).
I went conservative and ran it at only 3A to get a feel for things. The tint dedomed isn't bad and while it was too late to measure it, it does seem like it puts out more lumens than any other XP-E2 I've seen. I will get some OTF measurements, then it's time to see how high it will go before it pops.

I too found the de-domed tint to be pretty decent.

I leave the testing to you guys that are better equipped to do so. I could blow em up all right, but probably wouldn’t have much pertinent data to go with the pile of little smokies.

Once again I feel the pain of being the last (of the first, I admit ) to get my hands on a promising new led (3A and still improving output sounds like a killer, Richard!).

I will tell the family that we will move to the US before the next led comes on the market.

Well djozz, you have some heading at you… might be on the back of a mule though, don’t know. lol

They’re coming, anyway.

FWIW I just measured 323 lumens OTF of my cheap plastic lens zoomie flashlight with the dedomed XP-E2 torch @ 3A. Not sure that is worth much because I am probably getting some significant losses.

I might see where it pops, but I think I will let djozz do the true crash testing.

If these were used under a triple optic, would de-doming them help it to have a tighter hot spot? What amperage would be the goal for 3? 6A? Perhaps a little more? I’m thinking of building one of Wights PZL drivers and limiting it with chips to the 6A range for a triple in a small light. Don’t necessarily want a lot of light, just nicely collimated white light.

Any thoughts?

Oh, or would I be better off using a reflector and one emitter, de-domed? (at around 2-3A, not 6, of course. )

I got my emitters today. Pretty quick.. Thank you very much Dale! I owe you one..

Quickly tested: 270lm OTF from UF-T20 driven at 2.75A. Focus is not perfect yet, but even then I'm a bit disappointed on 54kcd throw compared to earlier 140kcd results from my similar(ish) XP-G2 mod (which was driven harder though).

Some of you are driving the XP-E2 Torch at 2.75+ amps it is stated. Don’t you consider this quite high for an E2, even an E2 Torch? My question results from data acquired from the thread located here comparing AL vs Cu sinkpads: Emitter Test Results pt4: XML2, XP-E2, XP-G2, and Nichia219! (along with sinkpad tests)

In the above thread it is seen that the output curve is rounding off at around 2.4A for the XP-E2. Above 2.4A, it appears the actual percentage gain would be very minimal in lumens. Of course you would have increased localized heat soak around 3A with the high value of 9 C°/W thermal resistance of the die (compared to G2 or especially L2 dies). IMO, I do not see much benefit running this emitter above 2.5A for maximum average gain, and that would be with a healthy size copper pill. At 3A, I would assume you may start with quite a bit more intensity than would be achieved if the test were repeated again 5 minutes later.

Thoughts?

Hi MEM, welcome to BLF :party:

You may be very right. The XP-E2 output even starts dropping fast above 2.5A. This led however, as claimed by Cree, is supposed to allow a bit more current than a normal XP-E2, that is why people start to do that. I have a few of these coming in the mail and will do a proper output test on a copper board to see what's going on.

I'm pretty sure that this led is no different than xp-e2,actually they're probably trying to get rid of junk bins,and there is no better way than making "new" led with different name).Cree claims higher driving current,but they do similar thing with xp-g in the past (raising max. current from 1 to 1.5A),but didn't change led's name.

If you look at the CREE Product Characterization Tool, you will see a lot more differences than just the higher max current rating. In fact, there are several ways that the XP-E2 Torch is worse than the “original” XP-E2 in the specs, according to the PCT. You should be able to get higher total lumens, though, because of the higher Vf of the XP-E2 Torch. If the die is exactly the same size, then surface brightness should be a bit higher, which should mean a little more throw. Really, if I were looking at this emitter as a replacement for either a XP-E2 or a XP-G2 emitter, I would not be impressed to buy any. The XP-E2 beats it in lumens-per-watt, at least, and the XP-G2 beats it in almost every way, except maybe die size (I don’t know the die sizes, so I’m unsure of that).

With a higher Vf AND a higher drive current, you should get a bit more light coming out the front. Efficiency ( lm/w ) is a little worse than “original” XP-E2 according to PCT. So, it’s like an engine in a car. You can get more horsepower, at the expense of fuel mileage. Overall, I don’t think CREE made any real “improvements” this time. I would define “improvements” as getting more light without costing more watts. For those that don’t care about efficiency and are looking for that last bit of increase in throw at any cost, the XP-E2 Torch may be a decent way to get that.

look at it this way:

We flashlight lovers like throw (don't lie, perhaps in secret, but you all do!) and that has everything to do with die surface brightness. The XP-E2 (and the XP-G2) has the die with the highest surface brightness on the market, and it is even not that much higher than of the good old XR-E die from 8 years ago. So despite the developement of all kinds of exciting new leds since the XR-E, surface brightness apparently is something that is difficult to improve. Now there is a led that seems to have a higher surface brigtness than whatever else is on the market. Even if the increase is 20%, that is a big deal.

Where do you see 20% brightness increase?

I'm getting 4.4% from PCT tool,but voltage is 0.1V higher,so lm/W difference is negligible.

But no one mentioned tint or cri difference,manufacturer can easily add more green phosphor for that 5-10% "improvement"(been there done that-cree?).

It was an 'if', meant hypothetical :-) , a test will tell it all, I will directly test it against a XP-E2 R3 (I do not have a R4 bin)

These are 10500K temp leds, aren’t they? That’s incredibly blue, way off the bottom end of the Ansi tint chart. So it makes sense that with less phosphor in the way and less aggressive conversion to the red end of the spectrum that’s going to account for most of the increased output and surface luminance. Right?

Oh and had to laugh at the green comment :slight_smile: Cree does have a love for the greener side of the spectrum.


Standard issue Cree lab equipment :wink: