[Review] Astrolux S43 (4x219C, 1x18650 or 1x18350, ramping side switch)

bmengineer · 2019-01-14T15:52:38.000Z

The Product

This is the Astrolux S43, a high powered quad-emitter light, and the first product sent to me from them. The light has a side switch, built in micro-USB charging, and a ramping UI. The included cell tubes mean the light can run on either an 18650 or an 18350 cell.

Astrolux S43

Astrolux has a good history making quad-emitter lights. First was the S41, a tail switch quad made from aluminum, and it’s matching S41S, which was a version made of stainless steel with a copper heat sink. This was followed by the side switch S42, which made the move to a side switch and added built in charging, but had a rather divisive UI. The S42S with the same stainless steel and copper was produced as well. Now, we have the S43, in aluminum, and the S43S, in aluminum with a copper heatsink. The unit I’m taking a look at is the S43, with four Nichia 219C emitters loaded into the front - it’s also available with higher output XP-G3 emitters, at the cost of beam tint and CRI.

Spoiler

This light manages huge output out of a single cell, and the light it makes it as great as you can expect from the 219C. I carried it a bit less than I expected to, mainly because I prefer lights this size to have a bit more reach, and I don’t like the idea of burning a hole in my pocket - but if you’re looking for huge pocketable output, you should definitely look at this one.

Physical Dimensions

The light measures 30.5 mm across at the widest point, just above the switch, and 19.9 mm in diameter along the body tube. With the 18650 tube, it measures 122.2 mm long and weights in at 89 g without a cell. Swapping in the 18350 cell tube brings the length down to 89.2 mm, and the weight to 74 g.

Build

The head of this light is the most interesting part - there are 4 Nichia 219C emitters shining into a quad optic. The plastic optic is covered with a glass window, and held in place with a slightly crenelated bezel. I would prefer a smoother bezel, as this one sticks out a bit further than necessary from the lens, but that’s a matter of personal preference. This is also something I’m sure to mention a few times - I have a liking of compact lights, and there are a few spots where this light seems to have added a bit more metal than I feel is needed. The bezel also has the brand and model etched into the anodizing.

Switch and head

Behind the bezel, one side of the light has the switch. Astrolux was thoughtful about the design here, and they did a great job. The rubber cover on the switch is domed, which makes it easy to find by touch. It’s held in place with a bronze colored metal ring. The area around the switch is milled out into the body of the light, so the switch itself is set in and difficult to press accidentally. There are red and green indicating LEDs behind the switch cover. This section of the light also has some fins cut into it to help with cooling.

Closed dust cover

Opposite the switch, a silicone cover keeps dust and debris out of the micro-USB port used for charging. The port cover seats into the port well enough, but the small toggle used to help remove it is easy to flip accidentally with a finger while using the light. I would not recommend submerging this light if it can be avoided.

Open dust cover

The body tube, whether the 18650 or 18350 is used, is smooth without any knurling or other decoration. There are grooves for the clip at both ends.

The tailcap is knurled, which is good for grip, and it has a lanyard hole as well. The tail is flat and can balance the light. The large hole in the light is for the tripod thread or spike, which are included with the light. I would rather these accessories were left out and the light shortened, as I don’t see either of them being particularly useful.

Tailcap

Inside the tailcap, the threads are square cut and anodized. Mechanical lockout is possible with a small twist. There are two nested gold-colored springs that serve as the negative contact for the light.

Tailcap innards

Inside the head of the light, the driver appears to be pressed into place. There is no spring at this end of the light - just the bare PCB for the positive contact. My light had frequent issues losing contact with unprotected flat top 18650 cells. I’m not sure if the cause of this is the bare positive contact, the length, or a poor connection, but it was noticeable and unfortunate. Button top cells would probably resolve this issue, but so would including a positive spring.

Driver and head threads

What’s Included

This light comes with a thorough kit.

Astrolux S43 (with the 18650 tube)
Lanyard
Friction-fit pocket clip
18350 cell tube
Tripod thread adapter sleeve
Stainless steel spike
O-rings
Paperwork

Ergonomics and Retention (and spikes)

This light feels good in the hand. The knurled sections of the tailcap make it slightly larger than the body, which along with the bigger head make sure it stays firmly in hand despite the smooth body. There's a hole cut into the tailcap to attach the included lanyard.

Multi-purpose tailcap hole

The pocket clip fits at a groove at either end of either of the included cell tubes. The clip loops back for a great deep carry, and won’t leave much of the light above a pocket at all. My one complaint with this clip is that it sticks out quite far from the body of the light at the point where it attaches. That usually catches on my pocket, and means I need to carefully thread the fabric into the clip if I want the deep carry.

Clip profile

The tail of this light also has a hole threaded into its base at a size compatible with most tripods. A stainless steel sleeve is included to reduce the size of the hole. The sleeve protrudes slightly from the base of the light, and makes tail standing slightly less stable when installed. It also has a groove cut into it so it can be removed with a flat screwdriver if installed too tightly.

I don’t personally see much utility in tripod threads on the tail of a light like this, and I would prefer a flat tailcap that added less length to the light and perhaps included a magnet, but I’m sure there are users that will appreciate this feature.

The light also includes a steel spike that can be threaded into this tripod attachment. The product page refers to it as a “tactical survival hammer”. I’m sure it would hurt if you hit someone with this, but I’m not about to test that theory.

Modes and Interface

This is certainly one of the major highlights of this light - the light uses NarsilM, which is a firmware that allows huge amounts of customization. You can configure basic things, such as switching from standard modes to ramping user interfaces, all the way up to setting the temperature you want the light to step down at. Narsil is complex enough that I could do a whole write up on it, but I’ll just say that it’s fantastic and I am extremely pleased to see more lights using this and similar interfaces.

I left the light in the stock ramping mode - single press for on or off, hold to ramp, double tap for turbo.

Light Quality and Beam

This light uses 4 Nichia 219C LEDs under an optic. The light is also available with 4 XP-G3 emitters instead, if you would like to give up CRI and color quality for raw output.

Looking into the optic on moonlight

Power and Runtime

This light can run off of either an 18350 cell or an 18650 cell - my tests were all performed with an unprotected flat top 30Q. In my experience, small bumps were able to break connection with the flat top cell, so a button top may work better.

The driver used in this light is a direct drive setup, which means a lot of things. First of all, almost any protected cell used in this light will not work properly - the current draw is high enough that unprotected cells are highly recommended. Secondly, this kind of driver means that testing performance is very touchy. A FET or direct drive light basically just straps the jumper cables from the batteries to the LEDs in turbo mode and hopes for the best. The good part of this is that you really get the highest possible output from the light, but the downside is that any slight change in temperature, cell, how clean the contacts are, or any other number of factors will drastically change the results.

Step downs from turbo

My runtime tests have been shortened here to show two separate starts at two different temperatures. In both cases, the light starts way up around 300% of the output once the light has been on for 30 seconds. During this time it gets extremely hot to the touch. Also in both tests, the light settles at about 15% of the output at 30 seconds, and stays there for the rest of the test. Notably, the light does not try to ramp back up after cooling down.

Charging

Charging of this light was measured at about 0.75 A at the USB port for the constant current phase of the charging. After 2.5 hours, the constant voltage portion of the charge starts. There’s a solid drop off when the charge current has dropped below 0.1 A to prevent the cell from trickle charging. Overall charge time was about 5 hours for this 3000mAh cell.

Charge curve

When the light is charging, the LED under the switch glows red. When charging is complete, it switches to green.

What about the D4?

I feel it would be unfair to finish up this review without mentioning the Emisar D4. The D4 has been out for a bit longer, and these two lights have a lot in common:

Available with 4 Nichia 219C emitters
Made of aluminum with other metals optional
Available to run 18650 or 18350 cells
Side switch running a ramping firmware
Direct drive setup for maximum output
Lots of heat and fast step downs

So what sets these two lights apart, and which of the two should you get? The Emisar is certainly a much more compact light - for me, that’s a big draw. The S43 has a lot of extra length in the cell tube and that tail cap. That being said, the D4 made a few compromises to get so short. One of the largest is that it can be very picky about the length of cells it supports, whereas the light being reviewed here today has plenty of room in the tube (maybe too much).

The goal to get the D4 as small as possible also means it loses out on a lot of extra features. Here’s what the S43 can do that the D4 can’t:

Integrated charging
Backlit switch
Lanyard loop
Tripod hole

So which is better? That’s tough to say. In the end, it depends on what feature set is more important to you. It’s also worth noting that the D4 has more options for emitters, optics, and body color.

Personally, I can do without the integrated charging and would lean towards the D4, but I have seen countless posts where people have asked for exactly this feature. I think the S43 could be improved with a shorter tailcap that had a magnet instead of a tripod thread, as both these popular lights are missing that feature.

Summary

Pros:

Huge, high CRI output
Backlit switch
Great ramping UI
Solid built in charging

Cons:

Step downs are quick and drastic
The light puts out too much heat for turbo to be usable for more than a few seconds
Light is too long for my liking and for my cells

netprince · 2019-01-21T23:20:37.000Z

Nice pictures and review… thanks

bmengineer · 2019-01-22T00:13:48.000Z

netprince:

Nice pictures and review… thanks

Thanks, glad you liked it!

DavidEF · 2019-01-22T01:27:00.000Z

Thanks for the review. I guess I don’t mind EDC lights being just a bit larger than what most people here on BLF seem to prefer. That being said, I think the S43 and S43S are ugly with the 18650 tube. I have the S43S with the 18350 tube, and I carry it clipped to my belt. The length doesn’t bother me. Sometimes I bump it on something unexpectedly and it pops off the clip and takes a tumble. That bothers me. But that happens with every light that I’ve clipped to my side. And it bothers me just as much no matter what size the light is when it happens.

bmengineer · 2019-01-22T02:49:35.000Z

DavidEF:

Thanks for the review. I guess I don’t mind EDC lights being just a bit larger than what most people here on BLF seem to prefer. That being said, I think the S43 and S43S are ugly with the 18650 tube. I have the S43S with the 18350 tube, and I carry it clipped to my belt. The length doesn’t bother me. Sometimes I bump it on something unexpectedly and it pops off the clip and takes a tumble. That bothers me. But that happens with every light that I’ve clipped to my side. And it bothers me just as much no matter what size the light is when it happens.

I just find if a light is going to be bigger, why not have some extra throw? There’s a lot of space I find to be wasted in this light.

Maybe I’m just bothered by all the dead space in the tailcap, and the fact it kept losing connection with my cells.

Macka17 · 2019-01-22T05:02:55.000Z

A lot of us like the larger torches. Just for holding and balance.
Those little square things are uncomfortable and ugly to look at.
I bought a S41 when they came out. (Copper head) came with short tube.
Which has never been out of it’s wrapper. I bought long at same time.
Why have that much power. restricted by that little power.
Sorta defeats the point I reckon.
But as a walkabout ‘spread’ beam. I’ve yet to see one much better
than the Haikelite HT08 I have. Very underrated.

xevious · 2019-01-30T15:23:23.000Z

“The light puts out too much heat for turbo to be usable for more than a few seconds”

I have the Nichia version. Ran it on turbo for over 5 minutes. By the 5th minute, it was starting to get a bit hot… still OK to handle, but if I squeezed hard on the head it was uncomfortable from the heat. Felt like it could keep going, but I wanted to do other things with it. The battery: Samsung ICR18650-26C. I don’t know what amps, but perhaps higher would draw more power and faster heat build-up. So… if you’re running too hot, use a lower amperage cell.

EDIT:
— 1st test was with weaker cell and I didn’t watch it continuously, hadn’t noticed it auto stepped down. But definitely on the weak cell it wasn’t getting too hot to handle. However…

I did another test with an LG LGABF1L1865, which is 4.875 mA. Yikes — NOW I definitely experience the same thing. It cut off at about 45 seconds and it was WAY too hot to handle. It cooled off fairly quickly, but seriously, you can’t leave your hand on that head for very long while it’s on turbo.

bmengineer · 2019-01-30T11:34:16.000Z

Running a lower performing cell or using a lower mode are both options, but I much prefer lights that manage the heat better themselves. Some people really love turbo burst, I’m just not one of them.

HorizontalHunter · 2019-01-30T12:27:54.000Z

I have the Nichia 219B version of the Manker E-14 ( same as the S41) and love the light. It is my go to light for out door activities and I have been thinking about an upgrading to a similar light that has the 219C LEDs.

Thank you for adding the D4 comparison. I’ve been debating between the two.

Bob

VrestoTaylor · 2019-01-30T12:54:51.000Z

xevious:

“The light puts out too much heat for turbo to be usable for more than a few seconds”

I have the Nichia version. Ran it on turbo for over 5 minutes. By the 5th minute, it was starting to get a bit hot… still OK to handle, but if I squeezed hard on the head it was uncomfortable from the heat. Felt like it could keep going, but I wanted to do other things with it. The battery: Samsung ICR18650-26C. I don’t know what amps, but perhaps higher would draw more power and faster heat build-up. So… if you’re running too hot, use a lower amperage cell.

turbo for 5 minutes?its not possible…maybe for 45 seconds or?

xevious · 2019-01-30T15:21:49.000Z

vresto:

xevious:

“The light puts out too much heat for turbo to be usable for more than a few seconds”

I have the Nichia version. Ran it on turbo for over 5 minutes. By the 5th minute, it was starting to get a bit hot… still OK to handle, but if I squeezed hard on the head it was uncomfortable from the heat. Felt like it could keep going, but I wanted to do other things with it. The battery: Samsung ICR18650-26C. I don’t know what amps, but perhaps higher would draw more power and faster heat build-up. So… if you’re running too hot, use a lower amperage cell.

turbo for 5 minutes?its not possible…maybe for 45 seconds or?

Sorry, I misunderstood as when it was said the light puts out too much heat, I was presuming too hot to hold and had to be manually stepped down.

What happened is that I wasn’t watching it continuously and didn’t notice the “triple flash” and that the light had automatically stepped down. On the cell I’m running with Nichia, the step down isn’t a tremendous difference, so I didn’t discern the difference having not seen the light do the step-down. But it is noticeable, as I ran the test again and yes, at just under a minute, the light flashed and then stepped down automatically.

I did another test with an LG LGABF1L1865, which is 4.875 mA. Yikes — NOW I definitely experience the same thing. It cut off at about 45 seconds and it was WAY too hot to handle. It cooled off fairly quickly, but seriously, you can’t leave your hand on that head for very long while it’s on turbo.

This is understandable. This is not a BLF GT. Just look at that tiny head and heat sync block. Not intended to be on turbo for long. So I think complaints are unfounded, asking too much from the technology. Is there a light this size on the market that can push out 2000 lumens for over 5 minutes without burning your hand?

VrestoTaylor · 2019-01-30T15:20:45.000Z

well i have s43s copper head…45 seconds or so and it goes down…stepdown,and then another stepdown…its realy not warm,its hot.and this happen in pretty cold winter here…

xevious · 2019-01-30T15:28:00.000Z

vresto:

well i have s43s copper head…45 seconds or so and it goes down…stepdown,and then another stepdown…its realy not warm,its hot.and this happen in pretty cold winter here…

It’s understandable that it will step down a couple times. That head feels molten hot. Just imagine what that emitter and PCB are going through. High heat for a long time on a frequent basis is a recipe for degrading the PCB components over time. Seriously for $27, it’s a great value for what this light is capable of. Putting massive sustained thrower expectations on it is like buying a Honda Accord and being mad that it’s not getting 35 mpg as promised, when you’re driving with full acceleration every time you leave a stop sign.

VrestoTaylor · 2019-01-30T15:30:07.000Z

yes yes i accept….the first model hasthe same turbo timer as the copper head?

xevious · 2019-01-30T17:53:04.000Z

vresto:

yes yes i accept….the first model hasthe same turbo timer as the copper head?

AFAIK, the only difference is the material of the head housing—everything else should be the same.

You can change the thermal thresholds in the NarsilM interface, but I would not recommend doing that… as you may end up damaging your light if you’re not careful.