Sofirn HS20 Headlamp Review

Sofirn has released the HS20, a dual-emitter headlamp offering both throw and flood. There’s USB-C charging, and indicating switches, too!

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Official Specs and Features

Here’s a link to the official product page.

Versions

Only one body version is available, but it’s available with different emitter options. Seen here is the Cree XHP50.2 (for throw) and Samsung LH351d (for flood).  There’s a new version now, though, which offers SFT40 in place of the Cree XHP50.2.

Price

The Sofirn HS20 headlamp is going for a very reasonable $41.99 now, and that does include the 18650 cell.  If you really, really don’t need a cell, you can save $2 by ordering without.

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Short Review

This seems to me to be a ridiculously solid headlamp and offers quite a robust feature set at a fairly reasonable price.  While I’m not sure about the logic of using a Cree XHP50.2 emitter for throw, the specifications are met so there’s no real issue there.  The user interface is good enough, and USB-C charging works well, too.  All in all this is a great headlamp!

Long Review

The Big Table

Sofirn HS20 Headlamps
Emitter:	Both
Price in USD at publication time:	$41.99
Cell:	1×18650
Turbo Runtime Graph	High Runtime Graph
LVP?	Yes
Switch Type:	E-Switch
Quiescent Current (mA):	0.03
On-Board Charging?	Yes
Charge Port Type:	USB-C
Charge Graph
Power off Charge Port	With cell: all modes Without cell: all modes Without tailcaps: all modes
Claimed Lumens (lm)	2700
Measured Lumens (at 30s)	2610 (96.7% of claim)^
Candela per Lumen	3.1
Claimed Throw (m)	136
Candela (Calculated) in cd (at 30s)	1172lux @ 2.287m = 6130cd
Throw (Calculated) (m)	156.6 (115.1% of claim)^
Claimed CCT	(mix)
Measured CCT Range (K)	5100-5500 Kelvin
Item provided for review by:	Sofirn
All my Sofirn reviews!

Sofirn HS20 Headlamps
Emitter:	Samsung LH351d (5000K, 90CRI)
Price in USD at publication time:	$41.99
Cell:	1×18650
Turbo Runtime Graph	High Runtime Graph
LVP?	Yes
Switch Type:	E-Switch
Quiescent Current (mA):	0.03
On-Board Charging?	Yes
Charge Port Type:	USB-C
Charge Graph
Power off Charge Port	With cell: all modes Without cell: all modes Without tailcaps: all modes
Claimed Lumens (lm)	1000
Measured Lumens (at 30s)	944 (94.4% of claim)^
Candela per Lumen	2.2
Claimed Throw (m)	136
Candela (Calculated) in cd (at 30s)	273lux @ 2.609m = 1858cd
Throw (Calculated) (m)	86.2 (63.4% of claim)^
Claimed CCT	5000K
Measured CCT Range (K)	4600-5000 Kelvin
Item provided for review by:	Sofirn
All my Sofirn reviews!

Sofirn HS20 Headlamps
Emitter:	Cree XHP50.2 (6000-6500K, 70CRI)
Price in USD at publication time:	$41.99
Cell:	1×18650
Turbo Runtime Graph	High Runtime Graph
LVP?	Yes
Switch Type:	E-Switch
Quiescent Current (mA):	0.03
On-Board Charging?	Yes
Charge Port Type:	USB-C
Power off Charge Port	With cell: all modes Without cell: all modes Without tailcaps: all modes
Claimed Lumens (lm)	2300
Measured Lumens (at 30s)	2495 (108.5% of claim)^
Candela per Lumen	6
Claimed Throw (m)	136
Candela (Calculated) in cd (at 30s)	789lux @ 3.032m = 7253cd
Throw (Calculated) (m)	170.3 (125.2% of claim)^
Claimed CCT	6000-6500K
Measured CCT Range (K)	5500-5700 Kelvin
Item provided for review by:	Sofirn
All my Sofirn reviews!

^ Measurement disclaimer:  Testing flashlights is my hobby. I use hobbyist-level equipment for testing, including some I made myself. Try not to get buried in the details of manufacturer specifications versus measurements recorded here; A certain amount of difference (say, 10 or 15%) is perfectly reasonable.

What’s Included

• Sofirn HS20 headlamp
• Sofirn 3000mAh 18650
• Headband
• Charging cable (USB to USB-C)
• Spare o-rings (2)
• Manual

Package and Manual

Note that this manual isn’t exactly right for the light shown here…. the user interface sort of indicates this is a single-switch light.  I’ll cover the UI as I see it in the User Interface section, and I imagine Sofirn will update the manual in time.

Build Quality and Disassembly

Something I found peculiar is that the two tailcaps do not have the same threads.  I can’t think of a good reason for this, except that one has all the CE type information and one has the USB-C charging icon.  Seems like it’d have been better to make the threads the same (so that the tailcaps were “reversible”) and marked the body with this information.  But it’s fine; rare is the case where you’ll need to have both off at the same time anyway.

Size and Comps

Sofirn doesn’t actually give measurements on the Sofirn HS20 headlamp on their webpage, except to say that it weighs 2.8oz.

Here are my measurements:

Length: 86.17mm
Diameter (tailcap): 26.02mm
Diameter (narrowest body) 23.02mm
Diameter (across body and emitter area, ie the “height”): 45.67mm

The website does give dimensions, though:  83.5mm x 48mm x 26mm, and 79g.

If the flashlight will headstand, I’ll show it here (usually the third photo).  If the flashlight will tailstand, I’ll show that here, too (usually the fourth photo).

Here’s the test light with the venerable Convoy S2+.  Mine’s a custom “baked” edition Nichia 219b triple.  A very nice 18650 light.

And here’s the light beside my custom engraved TorchLAB BOSS 35, an 18350 light.  I reviewed the aluminum version of that light in both 35 and 70 formats.

Retention and Carry

The Sofirn HS20 is primarily a headlamp. As such, the main way to carry it will be on the included headband.

This headband has a silicone holder into which you must push the HS20.  It’s not hard, but you may have to really stretch these rings to make it happen.  Once in place, the HS20 stays put nicely, but can be rotated.

The over-the-top section of the headband can’t be taken off temporarily.

Below you can see the part that touches your head when wearing this headlamp.

Here’s why that top band isn’t temporarily removable.  The loop is sewn on.  You could probably take it off ‘the long way’ (by unthreading everything and all that) but it’s not a quick solution.

There’s no other way to carry the Sofirn HS20 headlamp.  I was surprised to note that neither tailcap has a magnet. Maybe that wouldn’t add any usefulness, but I seemed to find myself wanting that feature frequently with this light. (But that’s a “during testing” wish, not a “during usage” wish.  To be fair.)

Power and Runtime

The Sofirn HS20 headlamp operates on a single lithium-ion cell.  I have a package that had a cell included.  It’s a 3000mAh button top and is a completely standard cell.

The cell goes into the light in what feels like the “usual way” (which is to say that the positive terminal of the cell goes into the light).  There’s a little silk-screened logo on the front of the body to help with orientation, too.

Here are a number of runtime tests.

 

Charging

The Sofirn HS20 headlamp also has built-in charging, by way of a USB-C port on one end.  The charge port cover is a screw-on cap, which provides great protection for the USB-C port.

An appropriate cable is included.  USB to USB-C.

Both USB to USB-C and C to C charging work, and the profiles look about the same. Charging is fairly quick, at around 2h 20 m.

Powerbank

I’m a little surprised that a powerbank feature isn’t built-in, but I tried and it did not seem to work as a powerbank.

Modes and Currents

Both:

Mode	Mode Claimed Output (lm)	Claimed Runtime	Measured Lumens	Tailcap Amps
Turbo	2700	1.6h	2610	13.12
High	1000	2h	1122	4.52
Medium	350	8h	318	0.87
Low	100	26.3h	92	0.31
Eco	12	150h	11.6	36.7mA

Note that the “Both” section above (and in all the sections below) is just a bit arbitrary.  That’s because any mode from the spotlight can be used with any mode of the floodlight, so mixing them such that I advance each through their respective modes to match is just a random choice.

Throw:

Mode	Mode Claimed Output (lm)	Claimed Runtime	Measured Lumens	Tailcap Amps
Turbo	2300	2.9h	2495	10.50
High	900	3.5h	1052	3.25
Medium	300	10h	276	0.64
Low	60	38.3h	83	0.19
Eco	10	312h	8.8	23.3mA

Flood:

Mode	Mode Claimed Output (lm)	Claimed Runtime	Measured Lumens	Tailcap Amps
Turbo	1000	2.9h	944	6.35
High	400	4h	454	2.16
Medium	150	14h	139	0.50
Low	40	45.3h	37.1	0.15
Eco	5	312h	4.2	19.5mA

Pulse Width Modulation

Flood:

Spot:

Both (at the same level in each mode):

For reference, here’s a baseline shot, with all the room lights off and almost nothing hitting the sensor.  Also, here’s the light with the worst PWM I could find.  I’m adding multiple timescales, so it’ll be easier to compare to the test light.  Unfortunately, the PWM on this light is so bad that it doesn’t even work with my normal scale, which is 50 microseconds (50us). 10ms.  5ms.  2ms.  1ms.  0.5ms.  0.2ms.  In a display faster than 0.2ms or so, the on/off cycle is more than one screen, so it’d just (very incorrectly) look like a flat line.  I wrote more about this Ultrafire WF-602C flashlight and explained a little about PWM too.

User Interface and Operation

There are two switches on the top of the Sofirn HS20 headlamp.  These switches correspond to the emitter below and essentially they make this HS20 two separate flashlights in one.  The user interface is the same for each switch (as far as I can tell, more on that later) and the lights can be operated independently.

They also, as you can see above, have an indication feature. I don’t see in the manual where these switches actually indicate anything, though.

Here’s a UI table!  Again, the switches seem to have the same action for their respective emitter, and no action on the opposite emitter (except in one instance). So again, the HS20 can be seen as two lights with the same UI.  I’ll describe it as such, and not differentiate between the two.

State	Action	Result
Off	Click	On (Mode memory)
On (Except Turbo)	Click	Off
Any	Double Click	Turbo
Turbo	Click	If Turbo was accessed from Off: Off If Turbo was accessed from On (any on state): Previous mode (except Eco!)
On	Hold	Mode advance (LMH only)
Off	Click Either Switch 3x	Lockout (for both emitters!)
Lockout	Click Either Switch 3x	Unlock to high on whichever switch was used to unlock
Off	Hold	Eco mode

As far as I can tell, there isn’t a strobe group on the Sofirn HS20 headlamp.

LED and Beam

Two emitters are used in the HS20. At left below is a “6000-6500K” Cree XHP50.2, which is the “throw” emitter. At right is a Samsung LH351d emitter in 5000K CCT, which is the “flood” emitter.

Using a Cree XHP50.2 for throw might seem a bit strange, but the light does hit the specification for throw. However, Sofirn has updated this light with a new version and the throw emitter is a much more suitable SFT40, and probably throws much farther.

LED Color Report (CRI and CCT)

Flood:

Spot:

Both (at the same level in each mode):

Beamshots

These beamshots are always with the following settings:  f8, ISO100, 0.3s shutter, and manual 5000K exposure.

Tint vs BLF-348 (KillzoneFlashlights.com 219b version) (affiliate link)

I keep the test flashlight on the left, and the BLF-348 reference flashlight on the right.

I compare everything to the KillzoneFlashlights.com 219b BLF-348 because it’s inexpensive and has the best tint!

Conclusion

What I like

• Fairly low cost
• Simple user interface
• It’s like wearing two headlamps in one
• Lights can be operated completely independently, allowing user to achieve whatever level of flood/throw mix is needed
• USB-C charging works well
• USB-C port is well covered
• Very good build quality
• Throw emitter is warmer than the 6500K claim

What I don’t like

• Cree XHP50.2 is a strange choice for throw (but throwy emitter is now available anyway)
• Tailcap threads don’t match – tailcaps aren’t swappable

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Notes

• This content originally appeared at zeroair.org.  Please visit there for the best experience!
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