Spark ST6-500CW Headlamp

The first headlamp to arrive at Layman’s Lights is definitely a momentous occasion. Spark flashlights’ newest and brightest model is my inaugural edition in a new, widened field of reviews.

Spark ST6-500CW

Spark ST6-500CW

Meat and Potatoes

While in my opinion, a headlamp is inherently a fashion faux-pas in any form, little can be denied about their usefulness. Hands-free illumination is the ultimate in convenience when more arduous tasks must be performed after dark. The ST6 definitely falls into this useful category. The fully adjustable straps make for a very secure fit, with no sloppiness to distract you during use. The actual attachment that holds the removable light on the straps is made from durable rubber and is snug enough to hold the light in position wherever you set it, but yet still allow for adjustment to angle the light to suit your specific needs at any time.

As far as headlamps go, though I’m not up on the entirety of available models, the ST6 appears to be no slouch. A top end 500 lumens of power with extended runtime available at the 320 lumen level. Spark has chosen to use a single 18650 cell to power this light driving the current best-in-class LED, the Cree XM-L. For you bin code junkies, I believe this to use a T6 Bin. Nestled in a lightly textured reflector that is on the shallower end of the spectrum, the XM-L provides quite a useful floody beam of light that is very adequate for the short range tasks that generally accompany a headlamp. If that isn’t enough however, Spark Technology has offered the option of swapping out the “ultra-clear” glass for a frosted diffuser option. This takes an already smooth beam, with a wide transitional corona and transforms it into a beautiful hotspot-free veritable wall of light. In my opinion this is the ideal option for a headlamp. I don’t want to induce a tunnel-vision handicap when I am using technology to remove a dark induced one.

Frosted Lens

Frosted Lens

One of the biggest curiosities about the ST6 is that Spark informs the user that battery polarity is omnidirectional. You are able to insert the cell into the light either direction without fear of repercussion. How exactly this unique feat is accomplished I have absolutely no idea, but I am most certainly a fan of the concept. Since the head of the lamp is facing 90° from the power yielding body, it could be very difficult to remember in a dark, potentially tense situation whether you needed to insert the cell + or – first. Also, because of this concept, it inherently allows people looking for the highest capacity cells available to use their favorite flat topped 18650’s without having to worry about using spacers to simulate a button top cell.

Spark has offered the user a nicely spaced compliment of 4 output levels that are very adequate to meet your needs. From a soft glow (though not a “moon mode”) on low to blistering output on high, the ST6 covers a very wide range of illumination needs. The UI is a fairly uncomplicated one involving pressing and holding the switch while the light cycles through from low to high. Modes are memorized but the ramping always starts with low first, even if you enter mode selection from medium 1 or 2. This makes for a very useful UI, especially when combined with a light touch electronic switch like this one. The blistering 500 lumen “Super” mode is available instantly by a quick double click, though it is time limited to 5 minutes presumably to protect the LED from overheating at this high current.

Spark ST6-500CW

Spark ST6-500CW

Constructive Criticism

One of my biggest points with any light has always been quality of construction. There are lights I have reviewed that I just can’t seem to put down because of the precision machinework, or amazing durability, or simply attention to detail. The Spark ST6 however doesn’t appear to fall into any of these categories. The aesthetics are fantastic, showing a capacity for design, but the body of the lamp just seems like it is lacking something. There is a thin, roughness to the metal of this light that just feels as though it would not quite stand up to rigorous abuse as some lights would. Being a headlamp, this might not be entirely problematic, but I do dearly wish it was better.

I just today ran across something that I am very curious about. After having this light sit for a few days unused with originally a freshly charged 2400 mAh 18650 in it, I today was greeted by a completely dead cell that would not power the light at all. My biggest concern here is parasitic drain emptying the cell, but that doesn’t seem like it could have possibly been the case in such a short period of time. Alternatively, (and more likely) it could be simply that the soft contact electronic switch managed to be activated while the headlamp was being stored in a bag. Either way it appears that I will have to strongly recommend locking out the lamp when not in use. I will have to look further into this to determine the actual cause, though the end results for the user are identical.

Thin metal cap

Thin metal cap


An incredibly useful headlamp sporting a true plethora of lumens and an enviable beam (when properly equipped). Its seemingly lower build quality calls into question durability, but on the whole it appears capable.

Provided for review by the kind folks at Spark.

Bookmark the permalink.


  1. Dave, anything more on the possible parasitic drain on this light?

  2. Well, my multimeter was giving me some rather odd readings when I tried using that so I really didn’t trust it. Real world testing however has continued to support my theory of accidental activation being the culprit. It’s been sitting with some use on the same cell for longer periods of time now and still has plenty of juice to light up high and even Super.

    If I can ever get consistent readings off my multimeter I’ll be sure to post them here, but it really looks like you just need to watch yourself with that switch.

  3. That’s good. Recently ordered a 460nw and was hoping this wasn’t a problem in the ST6 line.

  4. This is a while after the review, but you never know someone might be looking, the 500CW is still a current model…

    As regards durability and ‘thin metal’ endcaps etc…..believe me, the ST6 is highly durable. I’ve used it as my main caving light for several years now and it’s been through some VERY hard usage (think semi-submerged in grit/mud/water porridge for hours on end). Even the electronic switch, which I thought would be most likely to go, continues to work flawlessly without problems.

    As regards drain, if you unscrew the battery endcap by half a turn or so it ‘disconnects’ the circuit, et voila, no parasitic drain. This is so easy and I’ve come to really appreciate it – it takes half a second to disable the lamp…and half a second to re-enable it. Cinch.

    Do not underestimate the build quality, which perfectly I find absolutely fine. This lamp can go through hell and high water, and back again.

    Having said that, I dropped a Fenix LD1 down a 40m shaft and it lay submerged in a streambed for 2 weeks before I went back down the cave and found it. It still works, too!

Leave a Reply

Your email address will not be published. Required fields are marked *