Sofirn SP33 V3 Review (3500 Lumens, Multi battery compatible, Very Affordable)

The SP33 seems like it should be a good light… but wow, that runtime graph. Others have noticed the same thing, and it’s probably the least stable thermal regulation I’ve ever seen on a flashlight. Kinda wondering how that got through testing.

Ya It’s the most active I have seen with the testing method I have now.

Great review- very thorough! :+1:

I am waiting on a 5k version of this light. It is stocked out along with the k5 SD05 dive light (which I think also uses the 3V emitter?). I have the original SP33 with an XP-L2 (or it might be an XPL); got it several years ago. Its been a handy light since doing duty at the back door for checking varmints and stepping out for the occasional cigar :smiley:

Also have the V2 and that’s a good pack light with really good run time on high (steady 900 lumens if I recall). I wonder with the size available for the driver if there may be an Anduril version in the future? But with 21700 batteries around 5k (and 26650s phasing out), maybe not.

I understand the thermal “swing” can be an issue for some, but the V3 with a good turbo output is still a light I want. When out camping/hunting this light has plenty of output where I doubt I’ll notice the delta in thermal regulation- and I’ll appreciate that bright turbo when needed (usually for a short time of course).

I’ve been weighing the SP33v3 against its half-sibling, the EC01, for my next purchase.

Between two very similar lights, the poor hysteresis in the SP33’s controls is turning out to be the biggest factor in favor of the latter.

If I understand correctly, the EC01 runs fairly old firmware from the SP36. It’s not really built for use on a smaller light, and isn’t calibrated well. Its thermal regulation probably isn’t great either.

This might get fixed eventually, but isn’t yet.

Personally, if I was looking for a 26650 light similar to SP33, I’d go with a D4Sv2. It costs a bit more and doesn’t have built-in charging, but it’s otherwise a pretty solid upgrade.

I like both - the SP33 V3 and the EC01. Just got my 2nd EC01 in, this time the 5000K version. Both lights are great deals for what you are getting, but yes, not thermal regulated well at all.

Yes, my understanding is that it uses an older version of your firmware, and the regulation isn’t great, but it doesn’t vacillate as frequently as this, nor noticeably, as I’ve seen mentioned in another review.

Ironically, the older SP33v2 steamrolls them both (pun intended) in this respect, but I’m not really certain about its availability, or gamble that I’d receive the desired version.

Other factors are playing a role as well, and I wouldn’t regret either choice, but the number of checks in the other column are totaling higher, and this one is more emphatic.

Budget lights come with compromises, and working through which are more acceptable is part of the game.

I’m aware that there was a period of controversy over the existence of the 5000k version, but that it was supposedly resolved.

Even so, the end result was that the 5000k version didn’t turn out to be much different that the 6000/6500k version. Is that what you’ve found?

Yes, very disappointed. After careful side by sides, I see no difference

Do you think the EC03 is running the same sp36 version as well?

If I understand correctly, yes.

In case it helps, I’ve been trying to track these things in a product firmware map.

Regardless of the thermal regulation being a bit of a see saw, overall I like this light. I’ve got the first version too and I think that Sofirn made some nice advances through the versions. I like the UI because it’s intuitive and I think I prefer the stepped mode over the ramping, but I’ll keep switching back and forth after I use it some more. I love the double click to turbo and the long press to moonlight. More companies oughta follow this. The ramping is faster than earlier Sofirn lights but a bit more speed to match my Q8 or FW3A and others wouldn’t hurt.

The things I really like are the use of different batteries, the heft of it and how it doesn’t seem to get into the danger zone with heat like some other smaller/lighter lights with similar lumen output. I feel ok handing this to a newbie after a bit of a lesson where I wouldn’t think of doing that with my Emisar D4 or other pocket rockets. A 26650 sized light just feels good in my hand. I’ve used it a good deal walking the dogs and walking the property to see if I can spy different nocturnal critters. It’s not for pants pockets but I did find a holster that I used for a Haikelite SC26. I upgraded to one of my Shockli 5500mAh cells (although the supplied battery works fine in this light as well as the first SP33 I have). I’m sure it’ll continue to see use around here.I guess lights like this just make sense. It’s a good price, very good output, easy to use, USB with a quality rubber plug (that some will like) and it’s flexible (cells and UI).

Thanks! I may eventually take a stab at modding your software. If i could just plug it into usb to update firmware i’d be hacking away already.
I wouldn’t call my self a coder but have worked with enough to understand the basics.

I wish they would put a little effort into modding your freeware, it seems sometimes they can’t be bothered to even post a link?
I would think some intern could take it home for a few days and just keep guessing and checking to modify software would be pretty easy and cheap, but it seems there’s just a rush to plop and drop to get the next flashlight release out the door.

Just curious, are those remarks prompted by some indication you’ve received that future production will incorporate a newer version?

Nice review!

Very neat PWM and runtime graphics. :+1:

If I understand correctly, newer production runs will use newer firmware.

Basically, I found out the IF25A exists because someone asked me why its thermal regulation wasn’t working. Also within a few days of that, I discovered that the SP36 was using a really old version of Anduril, and discovered the EC01 and EC03 are made by sofirn. So I contacted sofirn to get the firmware updated and get the license violations resolved. With any luck, maybe the smaller lights can get their own firmware too, instead of using something calibrated for a much larger light.

I don’t have the details though.

Good to know. Thank you for sharing that information.

I used zak wilson’s ‘ceilingbounce’ Android app and “ceiling bounce” the flashlight (almost fully-charged batteries, not particularly high-drain batteries used, since the flashlights were not cooled and was in a small enclosed room with no airflow, and ambient temperature is quite hot in our country all year long.)

(I didn’t do runtime until low-battery, but instead stopped manually when I notice the output was already very low and doesn’t seem to be moving much)

SP36 BLF Anduril runtime (first several minutes only)

Astrolux EC03 (uses Anduril) runtime (first several minutes only)

Yeah, that’s definitely old firmware which wasn’t intended for production use. I fixed it a few months after that for the FW3A release, and the thermal code has been rewritten twice since then. The current code isn’t perfect, but it’s a lot better than it was.

Pulling back from the stats & the charts, are you folks seeing these “swings” in thermal ramping with your naked eyes? I am having a hard time making out an appreciable swing up/down as captured in these charts.

I also have a hard time seeing lumen changes with my eyes. I suppose it’s a blessing for me. I’m really enjoying this light. My wife pretty much claimed it as hers and she is quick to grab it when walking the dogs. I get to use it mainly when investigating bumps in the night (dang raccoons!).