swapping emitter

I know we cant just post a link to promote a product, but i was wondering if anyone had this headlamp from Kai,

https://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2330

If you do can you have a look and see if the larger/single led is on an easily replaceable star. Would love to see this thing with a new Q2 or Q5(assuming you could sink the heat)!!

Also, if an LED states a typical driving voltage at 3.7v, what effect would direct driving 4aa (~6v on primaries) do?? I still dont understand the concept and repurcussions of overdriving. I know increased heat (and therefore reduced life expectancy) is a byproduct but does this generally also mean increased brightness?

Robert

(pls remove if belongs in another section)

there are several "global" things I'd like to point out:

1. when changing to a better emitter, heat generated is less, so this problem gets smaller by emitter swap
2. usually these lights feature a regulation circuit, no direct drive. Changing to other Voltage does not have that overdrive effect but will most likely fry the circuit
3. when the led is direct drive (direct connetion from batts to emitter) and You add one cell, the Led will immediately die from too much current
4. this light seems to use some kind of luxeon like emitter and most likely will have a star incorporated. Without opening it, there is no way to be sure
5. I would not use such a light and try one with ONLY the emitter and already a multistage circuit. Think of a PT Eos, f.e.
6. if changing to higher output (= more heat) only with metal body and direct connetion of sink to body

Yellow, congratulations, you qualify for my questions a many. I have a Black Diamond headlamp http://www.bdel.com/gear/zenix_iq.php that I am going to mod with either a Seoul Star or Cree on a star. Any advice?
I did take the headlamp appart and the lux lamp is on the star.
Any help would be appreciated.

just started with Seouls and have read in here, that they are better suited to luxeon focusing devices (but need to have them elevated just very slightly).

Cree will definitly not work nice with those (my impression).

then the usual advice: check the Star if the emitter is mounted thight.
There have been ones with an air gap between slug and star (I also got one of these)

I've got one of last years Zenix IQ's, which has the optic instead of the reflector. I soldered in a Seoul star, basically the easiest mod ever, and the result was outstanding. It did change the beam from a spot to more of a flood, but that was an improvement for my needs. Lot's of uniform light, and a huge increase in brightness. It's pretty much the only headlamp I use now.

This years Zenix IQ's have a reflector, and I don't know how well it would work with those.