asking the pros: which emitter and driver to use?

So, forum,

I’ve got something new in mind; yet I don’t really know how to pursue my plans.

Let’s say I do have the following:

- 3.3-4.2V power source, NiMH (sic!)

- orange peel reflector, 21mm wide and 15mm deep

- 7mm wide opening for the emitter

- enough space for a 17mm driver (nanjg 105 series, for example)

  • romisen forward clicky (I forgot whether it is a B3 or N3, this component will be the first to break anyway… I do have plenty of spares, though)

Thinking about the new XP-G2 and XM-L2, which one would you prefer? And, at what voltage should either be driven (my build will incorporate a pill turned from solid copper)? I want to squeeze the most out of this combo - it doesn’t necessarily has to be a thrower, it doesn’t necessarily has to be a floodlight, it just has to perform to the max.

As always, runtime on high is not an issue for me. A single mode would be enough; although an additional low mode would be the cherry on top. Whether or not the cells will stand up to that kind of abuse is not a concern.

So, given the limitations of the reflector and the power source, what would be the best choice regarding the emitter and the driver?

curious greetings and thanks in advance,


that’s a tough one, how are you mounting the cells (and which cells? aa aaa c d?)

what kind of host or making your own? do you want bright? I’m assuming with that reflector your expecting more flood than throw?

Assuming you are at 3.6 - 4.2v for the modes alone I’d pick a qlite fron ios, however if you want constant current I like the ld-25 drivers available from fasttech, ios, lck led etc, choice of 2 or 2.6a but its a two group driver and sees use in my edc tube light coupled to an xm-l 4c.

xm-l2 is going to be brighter at a given current but floody, xp-g2 more throwy for a given reflector.

I actually tend to lean towards xp-g2 myself, its a bit different ftom the normal choice of an xm-l2 and I’m happy with the output, more throwy but not dim either, I do tend to drive them pretty hard though and intend to try out some of the high cri versions from illumination supply soon in an edc host coupled to a qlite and driven by an 18650. No help to your design but an indicator of where I’m coming from.

I would consider a high CRI XML no need to worry about vF problems and you get better color.

good evening all,

back home from nine stressful hours at work to answer your questions (and thanking you for your input):

1) I neither expect the light to be an excellent thrower, nor a superb flooder. Given the dimension of the reflector, it will be neither of those. I just want to push the emitter to its limits as far as possible with its…

2) … 3xAA NiMH rechargeables in series. And yes, I do know that asking for that will eventually equal cruel, inhuman, despicable torture for the poor cells.

The host has already been stripped of the XR-E R2 it originally came with.

So, if I wanted to put an XM-L2 or an XP-G2 in it, how hard could either one be driven with a NANJG 105c? How far with stacked AMC 7135s?

The light in question will be a conversation piece, mostly. To actually put it to good use, a lower mode would be fantastic (yet, not mandatory; hence my thoughts about using a NANJG driver), and the Romisen forward clicky switch is already installed. If I should ever get it done, you will be treated to a lengthy review/build thread! :slight_smile:

JFYI: For my real life needs at work, 60-100 lumens are all I need for myself; 300-900 for customers. Less brightness = easier on the eyes. I’ve spent the past four weeks getting my things done with just a LD10, 80% on low, 20% on turbo. Well, autumn will be here, soon; time to break out the SRK again.

the question really then is whats the maximum you can get at a vf of 3.6v? because that’s all you can ever give the emitter direct drive and assuming the happy place that you experience absolutely no voltage sag what so ever, that’s the most you can do.

time to hunt fown match and djozz’s test threads and check the numbers, that will tell you your maximum.