Acebeam EC65 review (21700, 4x XHP35 HI, cool white)

I'm a little late to the the party, but this review is so good, I had to give you a shout out. Thanks, maukka. Love all the technical data, especially runtime charts and color rendition info.

I am impressed by the flat output levels once this flashlight steps down to about 800 lumens. Predictable, flat output is the main reason I prefer boost (and boost/buck) drivers over linear and buck.

The high-CRI Nichia version must be fun!

Buck drivers are actually great, and are actually better if you have a higher voltage source, as that means the contacts don’t need to be as thick to carry as much amperage than at lower voltages.

You just need 2x 21700 instead.

It looks like we will have some aftermarket boost drivers to play with soon. 3A@12v and 6A@6v. :+1: :smiley:

Yeah, I get that. And I know buck drivers can be more efficient. They don’t fight the battery as the voltage wanes.

Nevertheless, I like the perfect staircase-like runtime charts produced by buck/boost drivers such as the ones ZebraLight used in its older lights (old, ha, ha, like 2 years ago). If a mode activates at all, then I know I’m getting its rated lumen output. (That is, so long as thermal regulation hasn’t kicked in.)

I think the new 2018 EU headlight regulations for Class-3 e-bikes require this kind of flat output. Slow fading is illegal. Obviously, that’s good for rider safety in bicycle lights, but I like it in handhelds, too.

Just my bias.

Huh? Slow fading?

Why would that be illegal?

I’m guessing there is a legal minimum brightness.

In California, they are called Class 3 E-bikes. In the EU, "speed-pedelecs." These fun e-bikes have motors that provide "assistance" up to 45 km/hr (about 28 mph). The new regulations are designed to treat them more like scooters/motor bikes, so, yeah, light output must be consistent. No gradual dimming allowed.

Regular "pedelecs," which top out at 25 km/hr in the EU, are governed by less stringent regulations. In most jurisdictions, they are treated the same as regular bicycles.

I don't know much about these rules, except what I have read in passing. As I write, it occurs to me that I may be wrong in attributing them to the EU. They may be limited to Germany.

Great review OP . One of the most thorough I have read , most of it over my head but that is good to learn from.

Took some beamshots for the Fireflies ROT66 review and included the EC65. OP updated with comparisons to other TIR optic lights.

Very pity they consider their customers a sh!t.
I contacted them via their offsite email and asked about difference. How to spot the new batch from the first batch, which had problem of using high drain batts. Asked some other questions about charging etc. They answered that the light goes with their acebeam battery in package. Said not a word beside that.
Now, a rhytorical question.
Why to bother having deal with such morons.
They do not even respect the time of person who is contacting them.

Amazing review Maukka. Thank you for all the hard work you put into it… :slight_smile: :beer:

For reference, I measured the EC65 219C version at 1,910 lumens turbo with both 30T and VTC6A

The XHP-35HIs will be throwier than the other LEDs you mentioned using the same optics/lens but the alternative would actually XPL-HI to the throwier aspect. Bypass didn’t work well and I had to remove it. The Turbo was too powerful and tripped the battery I think (more amps out the battery after bypass but might work on a Molicel P42A :smiley: ). Less power is better in this case, so I think they went with that LOL. Not the most efficient design but it works and is compact with C charging at least. :stuck_out_tongue:

The voltage to the driver would go up and so would the power coming out of the battery which will trip it (according to my bypass attempt; had to remove the bypass)…

This light should definitely not use a protected cell.

I don’t remember what leds I mentioned.

What might work really well with this style of light is the newer SST-40. They are 3v and can do about 1800lm.

The SST-40 is an XM footprint emitter that can do over 2300 lumens, as a Luminus emitter it is power hungry and can consume over 8A… even 9A. Much different emitter than the XP footprint 12V XHP-35.

Should work well with a new mcpcb wired in series :+1:

Better yet, if we could find a 21700 host like the EC65 we could build something awesome for cheap.

Amperage is way too low to run 4S SST-40’s, the 12V XHP-35 maxes out at 2.5A, that’s barely getting started for the larger 40’s.

Yeah, not enough amperage. I wonder how the SST-70 at 12v would fair? It’s also a bigger footprint, but to really push it, it would need 3A-3.5A.