Sofirn LT1S Pro short review - the disappointment of the year

I want to warn you right away and apologize for the fact that this is not really a in-depth review, just a user-experience review as a consumer. Without measurements, graphs and photos (photos can be taken from here - ➤ Sofirn LT1S review (1*21700, 2700-6500K, Type-C) I think we have a winnner, the appearance doesn’t differ at all, except for the addition of “Pro” in the name). Although if you need, I can take a photo on my phone, I just don’t see the point. Let’s finish the introduction and move on to the review.

Briefly about the flashlight. As it is clear from the name, it is a copy of LT1S from here - ➤ Sofirn LT1S review (1*21700, 2700-6500K, Type-C) I think we have a winnner with improvements. Namely, the firmware is Anduril 2 and the LEDs are Nichia 519A 2700k + 5000k.

Why I bought it.
For the lanterns I had only Fenix CL26R, and in general it suits everything, except for the cold main light, and not very high quality and bright warm light. A lot of people also don’t like the stupid stepdown. In theory I don’t like it either, but in practice it has never strained me. Oh, and it shines too much in the eyes, not on the table for example, because of its shape (tapers to the top).
That’s why I always wanted to buy either LT1 or LT1S, but somehow had no reason to buy it. But here we were going camping, and a discount unexpectedly came up, though on LT1S pro. Looked that there nicia and anduril 2. And although for a camping lantern I think the simpler the better (a lot of people should be able to use it), I decided to take a chance, especially with a coupon it was sold cheaper than the non-pro version.

Pros:

  • light is divine. To the eye - no greenness, no violet - nothing. Very pleasant in the whole spectrum from 2700k to 5000k. Before that I considered my Lumintop FW3a on SST-20 to be the benchmark, but this one is even nicer, although I can’t say why.
  • Anduril 2. At first I thought it would be a disadvantage, but in simple mode everything, you know, is quite simple, and if necessary, you can customize everything in complex mode. Turn on, turn off - with a click. 2 clicks from any mode - turbo, change brightness by holding. This is from what is as clear and intuitive as possible. Changing the tint is a bit more complicated, but about it later, in the “Control” section.
  • Cool modes. Unlike LT1S, you can make the red like for one lumen, for example. And there is also a mode with red changing to warm, changing to cold (as brightness increases), there is a mode of auto tint adjustment depending on brightness (from warm to cold), there is a mode with red to white mixture on the whole range (and adjusting the percentage of this mixture). Of the really interesting - red-warm-cold and auto-temperature adjustment. In addition, I left pure red and manual temperature adjustment, the mode with admixture of red on the whole range was turned off. Modes are changed by 3C, temperature is regulated (where it is) by 3H.
  • All the pros from the LT1S - the shape of the flashlight which helps to shine down rather than in the eyes, 21700, charging on board, powerbank, etc.

Cons:

  • A conditional disadvantage is the controls. Although I liked the simple mode, and liked the possibility of customization in the main mode, I had to torture myself still. For some reason from the factory there was a manual memory on the timer. That is, you turn off in some mode (for example, 2700k at half brightness) - a minute later turn on in same mode as well. And after half an hour - it’s turn on in a mixture of red and white (wtf??). To fix it, in the main mode you need to make 10H (10 clicks with holding the last one) and after the first flash you release, and when it starts flickering - press once. Then auto-memory will turn on and everything will work as it should. But for my wife, even with actual manual, it will be pretty much impossible to fix. So no matter how simple the simple mode is, the need for initial customization may arise.
  • Manual. It’s not incomplete, it’s just wrong. I had to google, go to reddits, read the text manual from the toykeeper and figure out what exactly is relevant to this lantern. Since the complete and accurate instructions for THIS flashlight, as I realized, does not exist in nature. For example, the manual says that in the main mode 3C (3 clicks) from the on state will switch us from smooth ramp to step ramp and back again. In reality, the 3C from on will change light modes (red, auto temperature control, auto with red, etc), and to change from step to smooth ramp, you have to make 6C. Or, nowhere does it say that 3C in the simple mode will also change the light mode, and 3H from off will turn on the strobes (very convenient, and then the manual these modes only available in the advanced mode. Also no one will tell you how to control the light modes (turning off unnecessary) and the type of tint control. In general, there are a lot of possibilities, and everything is realized quite well. You can read the full manual here - http://toykeeper.net/torches/fsm/anduril2/anduril-manual.txt.
    And many features of the flashlight are discussed here - Reddit - Dive into anything
  • PWM. It has a visible PWM at near-moonlight brightness. Very visible. And, most unpleasantly, audible PWM. At a brightness of about 50% to 95%. Maybe not so loud, but in complete silence from a 3-6ft away it’s easily distinguishable. To me, there should be no PWM in flashlights of this price category.
  • The moonlite level is too low from the factory. I didn’t think I would ever say such a thing, but realistically - you can barely see it in total darkness, while it illuminates nothing. Coupled with PWM at that level of almost 100 herz and 100% (by eye), this option is better not to exist at all. It’s THAT terrible Good thing it’s an Anduril, so I limited the moonlight to level 5 (out of 150). PWM is still visible, but not so terrible, and the flashlight at least illuminates something around itself within a few inches.
  • Whether it’s a bug, defect, or a feature, I don’t know. But the point is that the flashlight, without being particularly bright (it’s less bright than the tiny CL26R in maximum mode) resets “turbo” (funny to say) in a few seconds almost to 50% brightness. Coupled with the fact that at this brightness it starts to make noise, it is doubly unpleasant.

Controls.
I’ve already gone over it above, but nevertheless. If you want to fine tune it, I recommend to focus on these 2 links:
https://www.reddit.com/r/flashlight/comments/136fi05/sofirn_lt1s_pro_modestint_ramps_ui/
http://toykeeper.net/torches/fsm/anduril2/anduril-manual.txt
But as far as simple mode is concerned, it’s very simple indeed
1C - on-off
1H - moonlite while off.
2C - turbo from any
2H - turbo with smooth fall from off, just decrease of brightness while on.
3C while on - change color modes
3H while on - temperature change if applicable to current mode.
3H while off - strobes from on, 2C to change strobe mode, 1H to change brightness. From what is not in the manual (paper) - cool mode with flashing white and red, it is between Thunderstorm and Candle.
5H while on is the sunset mode. By default the flashlight will turn off after 5 minutes, if you keep holding the button there will be blinks, each blink adds 5 minutes.
This is all in a simple user interface.

The modes are described in the Pros. And if 5 modes are too much for you, and you want to disable some of them, you should do it this way. In the simple mode while off - 10C will switch to the advanced mode. Then, while on - 9H will take us to mode control. The lantern will start blinking, will do it 5 times. For example, we want to disable the red-white mode like I did. Then we need to wait for the 5th blink, and after it, when the flashlight starts to flicker, do not press anything. This mode will turn off. If we need to turn it back on, then during the flicker after the 5th blink, we need to press 1 time.
If the memory will be timed from the factory, then from the advanced mode you can enable auto-memory after 10H while on. The button should be released after the first blink and you should press the button 1 time during the flicker.
If you want to correct too low muntight for simple mode (there is no sense to keep the flashlight in complex mode at all, as even strobes and Sunset were moved to simple mode), from off state you should make 10H, release it after the first blink, and during flicker click as many times as you need brightness level on muntight. I don’t see the point of setting it below 5, for the reasons described earlier.

By the way, all this is difficult only on paper, in practice counting even 9-10 clicks is not difficult.

IN SUMMARY
The flashlight is, to put it lightly, a bit of a contradiction. If we assume that the immediate step-down from the already dim turbo mode is a defect specific to my unit, then the overall performance wouldn’t seem that bad, and the flashlight wouldn’t quite be a letdown. However, the visible PWM at low brightness and the audible PWM at medium-to-high brightness are considerable drawbacks, preventing me from deeming this flashlight a total success. Furthermore, the factory setting for a low, aggressively pulsating moonlight mode is perplexing — who exactly is it intended for? Thankfully, rectifying this seems straightforward.

On the other hand, despite these shortcomings (barring the confusion around the turbo), I’m leaning towards the pro version due to its intriguing modes, superior light quality, the option for red moonlight, and extensive customization possibilities. However, I would only recommend opting for the pro version if it’s priced lower than the standard version. Otherwise, the non-pro version would be my choice.

5 Thanks

that too bad

I wonder if there is a firmware update that solves those problems?

I haven’t had any visual issues with mine but there is definitely a small whine at certain ramp labels, have to be pretty close the light to hear mine

My extremely simple solution to this one -

I cannot hear it - not on any brightness level, not at any distance from my ear.

Ones mileage, of course, may vary…

Haven’t noticed any flicker on mine…

My teenager can hear the whine, I cannot. This is great because it ensures nobody’s gonna use my lantern!

Unbelieveable. Are you sure? Could you check please? Go to dark (bath)room, turn it on in moonlight mode and wave it around fast with your hand.

1 Thank

And also, does anyone have same issue with turbo stepping down real fast?

Having gone into this one from pre-release and following along with the 3-channel updates to Anduril 2, it wasn’t quite as bad an ordeal for me…

That said - you’re right about the essentially heartless lack of adequate instructions for the lantern. Anduril 2 is always daunting for the uninitiated and keeping up with changes doesn’t always let it get easier.

But, with time & practice - it’s pretty sweet. The updated UI is better, imo, than the previous versions. Combined with the really nice output from this lantern, I’m quite happy.

And, thankfully, I cannot hear the whine and see no flicker!

Man if I really wang my arms around I can pick it up faintly but I’m tiring myself out trying lol

I unpleasantly “discovered” my LED version of a circular fluorescent light flickers by just slinging my shirt over the shower-curtain bar, and saw the strobing effect.

Especially in an all-dark room with just the lantern providing light, take an almost-spent tube of paper towels, and wave it back’n’forth with the light behind you but still lighting the tube.

Sofirn sent me new light for free. It works fine, no step down from turbo

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Picked up an LT1S pro this week and I wish I had read this review before and got the non pro version. The audible PWM noise is damn annoying. The light output is great and I haven’t played with it too much but that whine/hum is disappointing.

Barry or Sofirn never did send me pone to review, but i been hearing is basically a cheaped-out, lower run-time, cheaper-quality attempt to build a smaller version of the very sucessful BLF LT1 a team of us developed & had them build a few years back. The LT1 dont have any PWM. - Den / DBSARlight

2 Thanks

The LT1 is entirely based on PWM.

The LT1S Pro uses the same 7135 regulators and the driver is very similar. The addition of the red channel made it necessary to reduce the PWM frequency because its regulator doesn’t support the short on-time. In the current state Anduril cannot drive multiple channels with different frequency.

Overall build quality and features are very similar between the LT1 and LT1S Pro. In my opinion the latter is just a smaller variant with some improvements. Nothing wrong with it.

(If you drop the red channel or accept a weird red ramp, it is easily possible to increase the frequency to remove the noise.)

2 Thanks

Wtf?

Why use a linear regulator for a lanter that is supposed to run as efficient as possible?!

I was going to buy a LT1 but after knowing it uses 7135 not buck driver, I won’t touch it with a 10 foot barge.

On the other hand, the old LT1S seems like a good deal.

In fact I am buying a diffuser for my Convoy S21F and use it as a lantern for now. Let me see, dual channel 519A tint ramping with Buck driver which also does 2000 lumens as a flashlight. Yep, it ticks all the boxes and more.

I meant to say no VISIBLE PWM.

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My eyes are particularly sensitive to visible PWM. I can barely detect it on my LT1 on lowest modes (depending upon tint), low enough that I’m not bothered. I don’t see any visible PWM in mid to turbo.

Some brands had rather visible PWM in low and even mid modes for years until they finally listened to the community and cleaned things up. The baseline has been good thus far. I’ve seen very little mention of visible PWM in reviews these days (and it’s usually about what can be seen in video). To go backwards and release a light that has visible PWM… is a serious blunder IMHO.

It doesn’t have visible PWM, because it uses PWM on 7135s - IIRC it’s the same basic driver design principle as the original LT1, just scaled down, and TK said that the PWM noise could be eliminated but it would make the ramp less smooth. Both the LT1 and LT1S Pro use PWM on a stack of 7135s. I helped TK get the newer refactor of anduril ported to the LT1. Anduril uses PWM on an output pin in every case on every single light, but that doesn’t mean that the actual driver circuit has visible PWM, in fact, the vast majority don’t other than a few cheap FET-only drivers.

AFAIK, actual energy efficiency isn’t that much different, it just has a smaller battery capacity. I have both an LT1S Pro and an LT1, and the LT1 gets a fair amounr of user when I need brighter, tabletop type lighting, but I use the LT1S Pro a lot up close on my desk etc, where battery capacity matters iess as there’s always power, and I want to put it in a small space that’s convenient, so I don’t care that much about runtime past a few hours on medium.

They both use linear drivers. The LT1 just has a larger battery capacity (4x18650 vs 1x21700). Neither one is ultra-efficient, but since the LEDs aren’t being driven hard then they still have fairly decent runtimes.

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The LT1s non-pro. I think it uses buck driver, no?

Oh, I misread and thought you said the LT1. I have no idea for the LT1S, I only have the anduril ones.