The Malkoff Front Porch

[ilikeguns40]

This Kosen 2700k M31LL is fantastic. Running a single AA seems just as bright as a 2xAA setup.

 

[dc38]

This Kosen 2700k M31LL is fantastic. Running a single AA seems just as bright as a 2xAA setup. View attachment 94737

that should last a little over 10hours at that brightness followed by a taper?

 

[ilikeguns40]

Based on Kosens specs it says 2xAA NiMH is 8 hours, which is awesome. One NiMH is around 30 lumens, but brightness to my eye looks about the same, not sure on runtime with a single.

 

[Schokokeks]

Based on Kosens specs it says 2xAA NiMH is 8 hours, which is awesome. One NiMH is around 30 lumens, but brightness to my eye looks about the same, not sure on runtime with a single.

Yeah, that whole thing about how light and sound are essentially a logarithmic scale is always a mind-bender. Double the lumens is almost imperceptible of a difference, but then "twice as bright" is measured at four times the brightness.

I put mine side-by-side as a single NiMH, and then 2xNiMH, and it was the faintest difference. Doing the comparison, I at least convinced myself I could see "something" different, but if you did a blind test on me, I don't think I'd score much better than chance.

Which is kind of cool, because it doesn't really matter what configuration I use this in, it's about the same.

The really weird one is that my M31W on a single AA looks just about as bright, too. I thought that was supposed to be about 90 lumens. Then again, 65 vs 90 is essentially the same to our eyes.

This reality will never stop entertaining me.

 

[ilikeguns40]

M31W I believe is 200 lumens

 

[GMT2330]

At 1.5v M31W is probably 90 lumens vs M31WLL at 3.0v 65 lumens.
That’s how I read it anyway.

M31W requires 1.8v for full output.

 

[Schokokeks]

Yeah, the M31 series is interesting in that you can get like half output if you run them on a single NiMH battery. That's why this M31LL was really neat; it's pretty consistent across its voltage range.

 

[md17]

Yeah, that whole thing about how light and sound are essentially a logarithmic scale is always a mind-bender. Double the lumens is almost imperceptible of a difference, but then "twice as bright" is measured at four times the brightness.

I put mine side-by-side as a single NiMH, and then 2xNiMH, and it was the faintest difference. Doing the comparison, I at least convinced myself I could see "something" different, but if you did a blind test on me, I don't think I'd score much better than chance.

Which is kind of cool, because it doesn't really matter what configuration I use this in, it's about the same.

The really weird one is that my M31W on a single AA looks just about as bright, too. I thought that was supposed to be about 90 lumens. Then again, 65 vs 90 is essentially the same to our eyes.

This reality will never stop entertaining me.

Any idea how long the m31w last on a single AA?

 

[Schokokeks]

Any idea how long the m31w last on a single AA?

From the INFRNL thread:

 

[md17]

From the INFRNL thread:
View attachment 94768

Thanks! As tempted as I am for the new drop in, I have to hold off. I have too many similar options and I recently bought the updated e2xtlv3 ezp. Nice to see that a couple hours of output is possible with the m31w!

 

[Schokokeks]

Thanks! As tempted as I am for the new drop in, I have to hold off. I have too many similar options and I recently bought the updated e2xtlv3 ezp. Nice to see that a couple hours of output is possible with the m31w!

The Kosen M31WLL is different, though. It's 2700K with a 519A. It's rated at 65 lumens at 0.3A draw at 3V, which the page says is 8 hours on x2 NiMH:

Malkoff M31WLL Light Engine (HCRI 519A 2700K, 2-3V)

Short Specs (full specs below): - Emitter: Nichia 519A LED - Optic style: McR-series textured reflector - CCT: 2700K - Power source: 2-3V - Output: 65 lumens - User Interface: single high output only - Runtime: 0.3A at 3V (typical 4.5 hours on CR123A, 8 hours on 2xAA NiMH) - Malkoff Devices...

www.kosen.one

It might be the last LL M31 made. Illumn isn't going to restock them, and that was about the only source of any of these, and apparently LLL or LLLL is now a no-go.

 

[md17]

The Kosen M31WLL is different, though. It's 2700K with a 519A. It's rated at 65 lumens at 0.3A draw at 3V, which the page says is 8 hours on x2 NiMH:

Malkoff M31WLL Light Engine (HCRI 519A 2700K, 2-3V)

Short Specs (full specs below): - Emitter: Nichia 519A LED - Optic style: McR-series textured reflector - CCT: 2700K - Power source: 2-3V - Output: 65 lumens - User Interface: single high output only - Runtime: 0.3A at 3V (typical 4.5 hours on CR123A, 8 hours on 2xAA NiMH) - Malkoff Devices...

www.kosen.one

It might be the last LL M31 made. Illumn isn't going to restock them, and that was about the only source of any of these, and apparently LLL or LLLL is now a no-go.

Ooookkkkkk fine. I bought one.

 

[flashlightinterested]

The really weird one is that my M31W on a single AA looks just about as bright, too. I thought that was supposed to be about 90 lumens. Then again, 65 vs 90 is essentially the same to our eyes.

I just tested my M31W with an Eneloop. It is ~50 lumens. It's possible a fresh alkaline or L91 would be higher since the voltage is a bit higher. (Edit: I tried a not-fresh-but-not-bad L91 and it's ~65 lumens. So it would vary based on what battery you tried. Even a fresh-off-the-charger Eneloop might be brighter for several seconds.)

I've done a runtime of the M31L 219b on an Eneloop, and it isn't good. You get 3 hours of ~100 lumens from 2 NiMH AA's, and you get an hour and a half of ~50 lumens from one NiMH AA. So one fourth of the lumen-hours from one half of the batteries. In a pinch, sure it works, but it doesn't seem very compelling (to me).

 

[dc38]

I just tested my M31W with an Eneloop. It is ~50 lumens. It's possible a fresh alkaline or L91 would be higher since the voltage is a bit higher.

I've done a runtime of the M31L 219b on an Eneloop, and it isn't good. You get 3 hours of ~100 lumens from 2 NiMH AA's, and you get an hour and a half of ~50 lumens from one NiMH AA. So one fourth of the lumen-hours from one half of the batteries. In a pinch, sure it works, but it doesn't seem very compelling (to me).

That's the single gripe I have about malkoffs...the runtime seems to indicate about 35-50% less efficiency than even electronically based lights...I suppose that durability and simplicity may come at the cost of less regulation?

For reference, I believe the Emisar d3aa and kr1aa each have around 250-300 lumenhours on a single 2500mAh NiMH AA, and roughly double that on a 5.55Wh 14500.

 

[md17]

Maybe I missed it, but what’s the expected runtime for the new M31wll on 1-AA?

 

[dc38]

Maybe I missed it, but what’s the expected runtime for the new M31wll on 1-AA?

That, my friend, is for you to discover and document for us! lol...however, probably less than half due to the boost circuit, lack of regulation, and higher draw to compensate the lower voltage. People did mention that it seems basically just as bright on either 1AA or 2AA config. But Kosen says it hits about 30 lumens on a single AA, and the 519A is pretty linear for the first Amp or so of draw...

My brain hurts, man. If it's at the lower 30 lumens, I'm just gonna estimate 6 hours accounting conversion losses. If it's around the same brightness, then I'd estimate around 2.5 to 3 hours because of boost inefficiencies and higher draw from one cell.

**disclaimer, i don't own one.

 

[md17]

That, my friend, is for you to discover and document for us! lol...however, probably less than half due to the boost circuit, lack of regulation, and higher draw to compensate the lower voltage. People did mention that it seems basically just as bright on either 1AA or 2AA config. But Kosen says it hits about 30 lumens on a single AA, and the 519A is pretty linear for the first Amp or so of draw...

My brain hurts, man. If it's at the lower 30 lumens, I'm just gonna estimate 6 hours accounting conversion losses. If it's around the same brightness, then I'd estimate around 2.5 to 3 hours because of boost inefficiencies and higher draw from one cell.

**disclaimer, i don't own one.

Ok. My goal is to try to get a non scientific run time for a single AA and the Keeppower 3v.

Currently I have the m31w in an older md3 (which is perfect for AA and cr123 size because most protected 18500 are too wide for this body) and I’ll swap it out with the m31w when I get it.

 

[Schokokeks]

I just tested my M31W with an Eneloop. It is ~50 lumens. It's possible a fresh alkaline or L91 would be higher since the voltage is a bit higher. (Edit: I tried a not-fresh-but-not-bad L91 and it's ~65 lumens. So it would vary based on what battery you tried. Even a fresh-off-the-charger Eneloop might be brighter for several seconds.)

I've done a runtime of the M31L 219b on an Eneloop, and it isn't good. You get 3 hours of ~100 lumens from 2 NiMH AA's, and you get an hour and a half of ~50 lumens from one NiMH AA. So one fourth of the lumen-hours from one half of the batteries. In a pinch, sure it works, but it doesn't seem very compelling (to me).

Yeah, the single cell output and runtime is never great, but the cool part is that it's possible. I'm currently trying to get Mark at Lumens Factory to make some lower draw drop-ins, and he said his voltage range would be pretty wide (NiMH through Li-ion), and with the lower draw, it might be a bit better.

That's kind of why the LL-LLLL M31 modules are neat; the lower overall output keeps things more even across single and double cell configurations, with run times that, while not record setting by any stretch, are fully acceptable.

I have a FiveMega MD1.5 I run a single Eneloop in with M31 drop-ins, and it's just a really handy package. It's one of my chunkiest AA lights, but that means it fits in my hand well. I currently have my new M31WLL in my LF 3PP body with their A19 extension (and a spacer for the cell to with), and it's essentially an 18650 body size, but runs my beloved Eneloops.

If you really like a single mode light, and just want something basic to run on an AA, these are cool.

The real advantage is, for a light I use to verify which color shirt I'm grabbing for work for a few moments, I only have to change the battery every once in a very blue moon, and since it's almost free to recharge an Eneloop, the disadvantage of runtime is essentially of no consequence.

The only time I every care about runtime is for my headlamps, and when setting up a light for emergency usage. Everything else? It's the first thing I'll sacrifice, hahah.

That's the single gripe I have about malkoffs...the runtime seems to indicate about 35-50% less efficiency than even electronically based lights...I suppose that durability and simplicity may come at the cost of less regulation?

For reference, I believe the Emisar d3aa and kr1aa each have around 250-300 lumenhours on a single 2500mAh NiMH AA, and roughly double that on a 5.55Wh 14500.

It's mostly because his lights are designed around CR123A batteries, which are pretty expensive on a per unit cost, so they are designed to keep running with a reduced output, chasing the drops in voltage along the way.

In comparison, most other lights are built around either NiMH or Li-ion chemistry, where you want to aim for ONLY having output within a certain range, then cutting off to protect the cells from over discharging. The other advantage to that is that you can design a more targeted regulation circuit, because there is a specific voltage band you DO want output, and then a voltage band you want NO output.

CR123A based lights want output until every last electron comes out of that little cell, haha.

The M31 is kind of the most extreme of this disadvantage, since it's a single cell...in a chemistry with a pretty bad discharge voltage curve.

 

[md17]

The M31 is kind of the most extreme of this disadvantage, since it's a single cell...in a chemistry with a pretty bad discharge voltage curve.

So does this explain why I keep setting off the protection circuit with the 3v Keeppower rcr123a? It has a max discharge of 1.5a

 

[Schokokeks]

So does this explain why I keep setting off the protection circuit with the 3v Keeppower rcr123a? It has a max discharge of 1.5a

Oh, that's interesting. The M31 probably doesn't have much of a draw. I wonder if your new M31WLL will still do that.

I think a lot of us have had mixed results with those buck circuit cells. I have one of those 2.4V Olight cells, and it just...constantly trips. A lot of these buck circuit cells will drop the voltage as they run to "signal" to devices they're nearing a certain threshold of capacity. While that is likely useful for something with a battery indicator, for lights, they tend to shut them off, haha.