JetBeam JET-I PRO (Cree R2) 1AA Review: Beamshots, Runtimes, and more!

[BillMPL]

Thanks, selfbuilt, for your excellent review, charts, beamshots, etc. Your reviews are setting a new standard for CPF, and I very much appreciate all the professional quality work you put into them. :thumbsup:

I too, couldn't agree more! Unbelievably thorough report. Thank you for all your time and effort. :twothumbs

Looking over the charts, it makes me even happier with my L1D Q5.



Bill

 

[EntropyQ3]

Swithed-mode DC-DC converters dont like being switched on and off hundreds or thousands times per second. It decreases their efficiency. Some converters are more effected by this more than others.

And that is not the whole story - there's also the factor that since PWM drives the light at max current for short bursts, the efficiency of the LED is the high-current efficiency. Which is roughly a factor of two worse at 700mA than at 100mA.

There are benefits to using PWMs - freely selectable levels (at least for the manufacturers) and constant tint. But efficiency isn't one of them. Using PWM the JetBeam should have roughly equal area under its output vs. runtime graphs. It doesn't, the low modes have some additional problem that lowers efficiency even more.

The Pro-I is a one trick pony. It's a nice trick, it's a good looking pony, but....

Nice review, btw. I trust Selfbuilts integrity and consistent methodology.

 

[machoamigo]

I always noticed one thing about all the Chinese manufacturers, its the lumen rating, they always hype their lights ratings. I guess they are only trying to sell their products claiming high outouts.

 

[BentHeadTX]

Great review and it answers a lot of questions for me.
I use 1 or 2AA lights on my bicycle helmet (2AA in the winter, 1AA in the summer) For road riding, the setup works well with my L1D/L2D RB100.
The next step is night mountain biking and things get a little more complicated. Two L2D Q5's on the bars and a 1AA light on the helmet. The 1AA has to be a thrower with a bright hotspot so not get drowned out by two L2D Q5's. I don't want the brightness of the two bar lights to not make me able to see the spot of the helmet light when looking around corners.
Great job to Jetbeam for making a 1AA light with a larger reflector, major output/heat sinking and the intense spot that will work for me. :thumbsup:
Now if they made medium have twice the runtime, I would be ordering some of them. Now to wait for the Jet-I Pro V2.

 

[CandleFranky]

And that is not the whole story - there's also the factor that since PWM drives the light at max current for short bursts, the efficiency of the LED is the high-current efficiency. Which is roughly a factor of two worse at 700mA than at 100mA.

Which method is Fenix using (L2D, P1D ...)?

 

[I came to the light...]

I always noticed one thing about all the Chinese manufacturers, its the lumen rating, they always hype their lights ratings. I guess they are only trying to sell their products claiming high outouts.

Hey, it's hard to measure up to Surefire and Pelican's truthfull ratings
JETBeam's the worst of that crowd... but there are some good ones; Dereelight doesn't even claim output levels, and they have quite a bit they could brag about.

Thanks a ton for the review. Amazingly helpful to clarify what exactly this light is... I'd be in for one for sure if only they'd fix the low and medium modes! And maybe the beam pattern... but that might ruin the point of this pocket thrower.

 

[Steve L]

Which method is Fenix using (L2D, P1D ...)?

Fenix lights are current controlled. They do use PWM on the LOD because of size.

 

[Steve L]

Most light makers look at the output chart put out by the LED manufacturers and quote emitter lumens. The problem seems to be some are changing the amount of current(pre-release spec) supplied to the LED(EX: lowering current because of runtime), but not changing the lumen rating(pre-release spec).

 

[Bernhard]

Yes, bring on Jet-I Pro V2 please...

 

[Stereodude]

Another disappointing JetBeam product. Frankly I'm not surprised. :sigh:

They burned me on the JetBeam C-LE v1.0 (which I bought on their hollow claims before there were reviews out), and I see they're still up to their old tricks. At least I learned my lesson the first time around. :laughing:

 

[Lite_me]

Another disappointing JetBeam product. Frankly I'm not surprised. :sigh:

They burned me on the JetBeam C-LE v1.0 (which I bought on their hollow claims before there were reviews out), and I see they're still up to their old tricks. At least I learned my lesson the first time around. :laughing:

That's a bummer. I bought the C-LE v1.2 and absolutely love it! I also have a v2.0 and I think it's great also.

 

[chimo]

Your review is very well done. Good stuff!

 

[Vikas Sontakke]

14500 Medium vs High is very interesting
With the medium, you get less light for shorter duration. What a bargain!!!

- Vikas

 

[Tubor]

Fantastic review selfbuilt and graphs thanks for the info. :thumbsup: Funny circuit IMO, but pretty good looking.

 

[selfbuilt]

Wow, that review certainly generated a lot of interest!

Thanks for all the support everyone :grouphug: ... it was a bit of marathon session getting everything done.

I can't cover all the excellent points raised in detail, but I'll make a few general responses.

Output vs other lights:
As I discovered with the R2 that came with my DBS V2, throw and output didn't exceed a Q5 (in fact, after the first few minutes on the DI circuit, it matched output and runtime of my Q4). It seems to be similar here - those expecting a big bump from Q5 are going to be disappointed, it seems.

That being said, my milk carton lightbox may not be the best for capturing overall output differences. The light is currently undergoing runtimes, but I'll do some ceiling bounce tests and add to the results later.

Output vs. previous JetBeams:
I'm just speculating here, but it seems to me the early Cree/SSC JBs were way over-driven (e.g. MkIIX, Jet-µ) likely leading to thermal managment issues and potential warranty claims. My MkIIX (with Cree P4) remains one of the brightest llights I've seen on 14500 - but its direct-driven and runtimes are <30 mins. Plus it gets super-hot! Similar heat issues on my Jet-µ.

The C-LE is a special case, since it was poorly heatsinked to start with, and was always intended as budget light (both contributing to its lower output, I suspect). Still a great light for the price, I may add ...

The second batch of JetBeam lights (MkIIR, Jet-II) instead opted for extended runtime and lower maximum output. Obviously, people weren't happy with that decision in premium-priced lights.

So along comes the Jet-I, and JB takes a very similar approach as EDGETAC and goes for max output on NiMH/alkaline, and reasonable regulated output on 14500. I think that was an excellent decision, by both makers. :thumbsup:

PWM vs current-controlled:
Readers of my reviews will notice that nothing beats Fenix' current-controlled output/runtime efficiency when it comes to low modes. But PWM can still do quite well (depending on a number of variables, as some have pointed out). I don't think the problem here is PWM per se .... but something is definitely off in the circuit design to produce those odd Med 14500 results.

Alkaline runtimes:
Just added some graphs, and things don't look too good for runtime efficiency on alkaline.

I don't normally do this, but I'm currently running Energizer e2 L91 lithiums, to see how they do at the various modes. I'll keep you posted!

P.S.: As I said in the review, I think it's appropriate to also compare this light to pocket throwers like the D-mini. In that regard, it's pretty impressive for 1AA ...

:wave:

 

[JCup]

Well, I have one on the way - but the review does reveal (or confirm) some issues.

Doesn't this tell us that for throw, this AA powered light is best compared to CR123 competitors, and that it is very nicely made?

I considered getting a Nightcore, but they don't seem to be available for sale, so in a way comparisons to other proto run products are less meaningful.

All in all, looks like the Fenix 1 AA solution may be the best choice (I really like my L2D CE Q5).

Thank you, Selfbuilt. Nice work!

 

[WadeF]

:
As I discovered with the R2 that came with my DBS V2, throw and output didn't exceed a Q5 (in fact, after the first few minutes on the DI circuit, it matched output and runtime of my Q4). It seems to be similar here - those expecting a big bump from Q5 are going to be disappointed, it seems.
:wave:

I don't think this is an R2 issue, but an issue with the driver powering the R2. You are comparing a R2 DI to a Q4 3SD (or whatever) which are using different drivers, etc.

A R2 should exceed the output of a Q5 if all things are equal. I have a R2 3SD and a Q5 3SD, and the R2 3SD easily out performs the Q5 3SD. My R2 DI doesn't perform as well as the R2 3SD, so the DI circuit doesn't seem to be performing that well, not the R2.

 

[LG&M]

:thumbsup: Outstanding review selfbuilt. Thanks for all the work you do for us.

 

[Steve L]

Wow selfbuilt, you really put alot of effort in your reviews!:thumbsup: Thanks. Hi Wade, that was my first thought. I have 2 3SD Q5 pills and they both outperform my 2 DI R2 pills. The only thing that makes sense is thet are not being driven as hard. I wish I would have bought a R2 3SD to compare to the DI's.

 

[Dogshund]

I hope Jetbeam offers some upgrade pills in the future once they get the med-lo sorted out. Maybe an OP reflector also.

You reading these posts Jetbeam?