Rexlight REX 2.1 vs 2.0: RUNTIMES, THROW, OUTPUT, etc - Now with 14500 runtimes!

selfbuilt

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Rexlight REX 2.1 vs 2.0: RUNTIMES, THROW, OUTPUT, etc - Now with upgrade module!

UPDATE 12/10/07: Kai has finally released the 2.1 upgrade module for the Rex 2.0. With a Q2 emitter and new circuit, with improved performance over the original 2.1 build. Scroll down to the runtimes to find out if this claim holds up (detailed discussion at the end of the post).

UPDATE 12/18/07: It seems the new upgrade module is the same as the new Rex 2.1 002 build. So the results you see below for the upgrade module should be the same for the Rex 2.1-002 currently available for sale.

For a comparison of the Rex 2.1 build 002 to my latest multi-stage 1AA lights, see: Multi-stage 1AA Review - Part III: Runtimes, beamshots & more!.

The lights:

Rex 2.0 on left (black finish), Rex 2.1 on right (natural finish)
Rex.jpg


Beamshots:

Taken on 2650 NiMH on Hi
Rex50.jpg


Clearly, overall output is reduced on NiMH on the original Rex 2.1. Hard to see in the image, but the Rex 2.1 has much more "ringy" beam than the original 2.0 (as others have noted as well). Also, in real life my 2.1 has a very yellow-green tint to the beam - I'd estimate WG tint at best. Here's a lower exposure to show you the hotspots better:

Rex125.jpg


Haven't done beamshots of the new Rex 2.1 upgrade module for 2.0 yet, as there are some centering issues to be worked out (see discussion at end of post).

Summary Chart for 2650mAh Duracell NiMH

RexSummary.gif


Method: All my output numbers are relative for my home-made light box setup, a la Quickbeam's FR.com method. My relative overall output numbers are typically similar to his, although generally a little lower. You can directly compare all my review graphs - i.e. an output value of "10" in one graph is the same as "10" in another.

Throw values are the square-root of lux measurements taken at 1m using a light meter.

Runtimes:

Rex14500.gif


RexMed14500.gif


RexLo14500.gif


RexHi.gif


RexMed.gif


RexLo.gif


Key Observations:

UPDATE: See bottom of this post for discussion of results for the Rex 2.1 upgrade module for 2.0

PWM
  • If this new Rex 2.1 uses PWM, I can't measure it on my sample. The Rex 2.0 ran at a noticeable 94 Hz.
  • UPDATE: Kai claims the new 2.1 upgrade module circuit is current-controlled
  • Strobe freq is 9Hz on my Rex 2.1, was 10Hz on my Rex 2.0.

Build Quality & Light Modes
  • Build quality is comparable, although the new Rex 2.1 only has one o-ring on the head and tailcap.
  • Beam profile of 2.1 is worse than 2.0 - more ringy and non-premium tint bin on mine. Note that throw has not decreased as much as overall output has on NiMH/alkaline, which may explain the rings - looks like they have adjusted the focus for better throw to help offset the lower output.
  • Last mode used memory actually works now on my Rex 2.1 on all battery types (the 2.0 would only remember on 14500). Memory is activated after 2 secs now, not 5 secs as on Rex 2.0
  • The Rex 2.1 features 3 sets of light states that give you access to different number of modes (see some of the other reviews here for an explanation). It's a bit clunky changing states, but it works.
  • See bottom of post for a discussion of the new 2.1 upgrade module for 2.0.

Output vs Runtime
  • I'm very impressed with the runtime increases of the Rex 2.1. Although max overall output has decreased slightly on NiMH/Alkaline on Hi and Low, runtime has nearly doubled in all modes. Low runtime is an amazing 2+ days on alkaline!
  • Output and runtime have increased on alkaline on Medium, although my graph looks a little wonky. I'll re-test and post the results here.
  • Output on Hi on 14500 has increased considerably, now within the range of other lights in this category (e.g. Jetbeam MkIIX, DX X.1, etc), but with litte effect on runtime. The light is not regulated on 14500, but I'm amazed at how long it runs!
  • Rex 2.1 is also much brighter than before on Medium on 14500. On Low on 14500, it runs for an outstanding amount of time (i.e. about 3X as long as the DX X.1 for the same output).

Rex 2.1 Conclusions:
  • All light modes now work as they are supposed to, on all battery types
  • Excellent runtimes on all battery types in all modes now. Outstanding performance on 14500.
  • Original Rex 2.1 was a worthy upgrade - only downgrades from 2.0 are in beam tint and ringiness on my sample

-------------------------

UPDATE: Rex 2.1 upgrade module for 2.0

This module was supposed to fix the problems with the original Rex 2.0, and bring performance up to at least the level of the original Rex 2.1. In fact, this new circuit is apparently identical to what you will find in the new Rex 2.1 build 002, which is an upgrade over the original Rex 2.1

Output vs Runtime
  • As you'll see on the updated runtime gaphs, this new module pretty much exactly matches the output of the original Rex 2.1 on 14500, with slightly extended runtimes on low-medium modes. :thumbsup:
  • On NiMH on Hi, output with this new module has increased to original Rex 2.0 levels, but with longer runtime. NiMH max output was reduced on the original Rex 2.1, so it's good to see max NiMH output of the Rex 2.0 has been retained in this upgrade module. :twothumbs
  • Output on lower alkaline modes has increased, which may not be an improvement for everyone. Output on medium is considerably brigther, resulting in lower runtime than the Rex 2.1 (runtime similar to Rex 2.0, but 2-3 times brighter!).
  • Output on low on alkaline is closer to Rex 2.0 levels, but runtime is similar to the dimmer Rex 2.1. Very impressive low runtime on alkaline at this level, supporting a considerable improvement in driver efficiency.

Build Quality & Light Modes
  • The new Rex 2.1 upgrade module for 2.0 now has all the light modes of the original 2.1 (i.e. daily, tactic, and advanced - cycled through the lowest output state of each).
  • Oddly, the emitter star is NOT epoxyed in place on the replacement module, but free floating on the brass pill (i.e. held down only by soldered wires). There does seem to be thermal paste on both my replacement modules, but since the aluminum reflector does not make contact with the emitter, there is no firm pressure holding emitter/star in place. This is likely to cause thermal management issues. :thumbsdow
  • Centering of the emitter with the supplied replacement reflector is quite off on both my upgrade modules. I suspect this is due to the non-epoxyed nature of the emitter/star on the brass pill. I will try to improve the centering and report back here. As it stands now, both poorly-centered setups lead to a dark semi-circular ring around the hotspot.

Conclusion:

This upgrade module does indeed bring the performance of the Rex 2.0 up to at least 2.1 standards - and even exceeds it a number of ways, as promised. But the lack of epoxy under the emitter star means thermal management issues are now a concern, and centering is rather haphazard (i.e. both of my emitters are noticeably off-center, and others have also reported the same). I would recommend those upgrading take care to properly center and epoxy their replacement modules in place. Other than that, this seems to be a fine upgrade for existing Rex 2.0 users.

UPDATE 12/18/07: Although this new circuit is also used in the new Rex 2.1 build 002, I don't have a sample of that light to directly compare. So I don't know if the emitter is epoxyied on the shipping Rex 2.1-002 - but runtime performance should be the same as shown above.
:wave:
 
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Re: Rexlight REX 2.1 vs 2.0: RUNTIMES, THROW, OUTPUT, etc.

Thanks for the very good comparison. Are you planing to add a chart for 14500? Looks like over all a very good upgrade. A few downs like lower high on nimh, and the sudden off on 14500, and of course ringyness(a word?). The tint may have been lottery though. Thanks again as this is very helpful.
 
Re: Rexlight REX 2.1 vs 2.0: RUNTIMES, THROW, OUTPUT, etc.

Thanks for the very good comparison. Are you planing to add a chart for 14500? Looks like over all a very good upgrade. A few downs like lower high on nimh, and the sudden off on 14500, and of course ringyness(a word?).
Yeah, I still need to do the Med/Low mode runs on 14500 (lightbox is tied up with a bunch of other lights at the moment). The sudden drop is not the Rexlight's fault - that's just the battery protection kicking in on my protected 14500s.

I think it's a very good upgrade overall, and plan to get a replacement module for my Rex 2.0 whenever Kai makes them available. Beam quality is the only drawback on mine, but I can live with a little "ringiness" and warmer tint - neither is a problem for outdoor use.
 
Re: Rexlight REX 2.1 vs 2.0: RUNTIMES, THROW, OUTPUT, etc.

Great review selfbuilt! I'm looking forward to your upgraded 1AA thread as I have a L1D on the way and am also trying to decide between the Dexlight X1 and the Rexlight 2.1. I love the look of the X1, but am concerned with the UI, tho I think I can make it fairly simple by keeping it in General Mode or just using the first 3 levels in Advanced Mode (high, strobe, low). The variability in performance and quality of the Rex concerns me that I will get a bad or lower performance/quality unit and I really don't want to have to return it. I've seen no complaints thus far about the Dexlight about quality or performance.
 
Re: Rexlight REX 2.1 vs 2.0: RUNTIMES, THROW, OUTPUT, etc.

Great review selfbuilt! I'm looking forward to your upgraded 1AA thread as I have a L1D on the way and am also trying to decide between the Dexlight X1 and the Rexlight 2.1.
I'm still doing all the other runtimes, but so far it looks like the Rex 2.1 is a real runtime winner on all battery types. The X.1 is brighter on 14500 by ~10-15%, but at the expense of less than half the runtime compared to the Rex 2.1 (just did the 100% X.1 test, and got 28 mins).

FYI, I'll be throwing in a L1D-CE Q2 with OP reflector into the testing mix for the next set of results (along with the DX/Kai 5-stage light, and new Luma 301). So far, looks like the Q2 is a good 20% brighter, with exactly the same runtimes as my 1st gen L1D-CE. :thumbsup:
 
Just updated main post with all mode 14500 runtimes.

Must say, I'm very impressed - that's about 3X the runtime on Low as the X.1, for the same output! :eek:oo:

Rex 2.1 definitely seems to be the best buy in ~$40 range at the moment.
 
Hi Selfbuilt. How do you like the UI on this light?

How about 14500, does it display a low voltage flash that allows one to change batteries before overdischarge, or is it too late by the time any flashing starts?

Looks interesting...
 
Hi Selfbuilt. How do you like the UI on this light?
It takes a little getting used (what light doesn't these days?) I like my lights to start on low, so that's a great feature of this sequence (Lo/Med/Hi) - but it's also a problem for mode switching, since that happens on low.

For ex, in "Tactic/Advanced" I have to remember not to turn it off within 2 secs of the double flash (i.e. between 4-6 secs after turn on), or I'll switch modes. That wouldn't be so bad, except going into Daily mode is somewhat annoying, since it uses a different timing - within 2 secs of the single flash (i.e. 2-4 sec after turn on) to change modes. What's annoying about that is 2-4secs time window in the Tactic/Advanced mode is when the memory feature is first activated - I need to remember to turn it off so as to get it to come back on at that brightness (assuming I don't want to wait for 6+ secs).

It's not quite as confusing as that description makes it sound, but I wish they had left the memory mode in Daily mode so that it would be consistent across all modes.

How about 14500, does it display a low voltage flash that allows one to change batteries before overdischarge, or is it too late by the time any flashing starts?
I'd say yes. I've only tested it in protected 14500, but the light flashed for ~30mins (on Low) and at least 1hr (on Med-Hi) before battery protection kicked in and turned the light off. That should certainly give you enough time to change an unprotected cell.
 
selfbuilt - any chance for a high runtime chart on an alkaline? Your high runtimes done so far are with 14500 and NiMH.

I'm still trying to decide between the Rex 2.1 and Dex X1. I know the Rex has a more efficient circuit, but I just love the way the Dex looks. Hmm...
 
Selfbuilt: Any plans on obtaining the new Rexlight 2.1 Build 001 to compare to these two models? It appears to have a completely redesigned stipled reflector so beam quality (I'm assuming) should be improved. Plus a new tailcap design and utilization of a Q2. I'm thinking the Q2 may push this beyond (or at least same) the brightness of the Dexlight. Brightness and looks are the only two aspects of the Dexlight I even liked compared to the Rexlight 2.1. So, one of the two may be gone:).
 
Hi Bobby ... yes, but I plan to only pick up two of the Rex 2.1 build 001 emitter/reflectors to go into my exisiting Rex 2.0 and 2.1 lights. I'm hoping they will indeed be nice, incremental upgrades.

I'll post my results here and in my multi-stage 1AA review thread.
 
Great! I look forward to it. You can purchase the build 001 now. Unfortunately, no one has seen the new upgrade modules for the 2.0 - 2.1 yet, so I wonder how long it will take for the 2.1 - 2.1 Build 001 module upgrades.....
 
Just updated main post with results of the new Rex 2.1 upgrade module for the 2.0. :thumbsup:

As you'll see, output is generally consistent with the Rex 2.1, but with slightly longer runtimes. Even better, max NiMH output was retained at the brighter level of the Rex 2.0, but with greater runtime.

Only negative is the lack of epoxy under the star on the upgrade module, resulting in centering issues and thermal concerns. See bottom of the first post for a discusison.
 
Just updated main post with results of the new Rex 2.1 upgrade module for the 2.0. :thumbsup:

Only negative is the lack of epoxy under the star on the upgrade module, resulting in centering issues and thermal concerns. See bottom of the first post for a discusison.

Hi Selfbuilt,

First of all, love your reviews. Thank you for taking the time to generate runtimes and graphs.

You mention the potential thermal issue. Did you do anything with your module before your testing? I'm just wondering if the module ran thru all your high mode runtime tests without any overheat problems.
 
+

Thanks selfbuilt!
as always, the most thorough test/reviews.

Can you use the old reflector with new module?,
....some people saying a so-so beam with new reflector.
 
Thanks for positive comments. :)

You mention the potential thermal issue. Did you do anything with your module before your testing? I'm just wondering if the module ran thru all your high mode runtime tests without any overheat problems.
No, I figured it was important to run the tests as shipped, to see if it would be an issue. But note that all my runtimes are done under a cooling fan (well, all runtimes above low anyway - I don't like leaving a fan going for ~2 days :)).

Thermal issues are not as apparent on the Cree as they are on a SSC, so hard to know if lifetime of the emitter will be shortened in this case. I plan to epoxy the stars down (while centering), which I recommend to everyone else.

Can you use the old reflector with new module?,
....some people saying a so-so beam with new reflector.
(Edit) The reflector is specific for the pill in the original Rex 2.1 - but you can mix and match the upgrade module with the old 2.0reflector. With the new reflector, the emitter is backed out a little further (probably in an attempt to minimize rings).

Beam profile is indeed so-so with the new reflector - somewhat more like the Rex 2.1, which was ringier than the 2.0. But some of that may be due to centering issue - I need to play more with mine to see if I can improve it. At this point, I can't say for sure what gives the best profile.
 
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I was able to use existing reflector from 2.0 light with 2.1 kit. I did not notice anything wrong with the beam with new led and old reflector.

- Vikas
 
I was able to use existing reflector from 2.0 light with 2.1 kit. I did not notice anything wrong with the beam with new led and old reflector.
Oops, you are right - I edited my previous post. Yes, you can use the old 2.0reflector (the emitter seems to sit a little higher in it if you do, and the head can be tightened down a little further on body since the whole pill actually sites a little higher). I need to play with it more to see what gives the best beam profile.
 
I'm getting confused. Is the upgrade module the same as the 2.1 or 2.1 002, or is there any difference between the two?
 
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