4Sevens Preon ReVO 1xAAA (XP-E R2) Review: RUNTIMES, BEAMSHOTS, and more!

[selfbuilt]

Warning: pic heavy, as usual.

Specifications:

• LED: CREE XP-E R2 Emitter
• Six modes of output
• Low: 1.5 lumens, 2.8 days
• Medium: 19.8 lumens, 5.7 hours
• High: 82 lumens, 0.9 hours
• Strobe: 2.5 hours
• S.O.S.: 2 hours
• Beacon: 48 hours
• Dimensions: Length: 2.8 in, Diameter: 0.5 in, Weight: 0.46 oz
• Power: One AAA battery (included)
• Operating Voltage Range: 0.9V~1.5V
• Material: Type III, hard-anodized aircraft-grade aluminum
• Lens: Optical grade glass lens with anti-reflective coating
• Estimated MSRP ~$44

The 4Sevens ReVO is a new member of the Preon family of AAA-based lights.

The light comes in fairly typical 4Sevens packaging. Inside the thin cardboard case with plastic insert is the light, spare o-ring, small split-ring, Duracell AAA battery, manual and warranty card.

From left to right: Duracell alkaline AAA, Tiablo E3A, 4GREER WS1, 4Sevens ReVo, Preon 1, Titanium Innovations LuminaTi, Lumapower Avenger GX, Eagletac PN20α, LiteFlux LF2XT, Maratac AAA, JetBeam Jet-u.

4GREER WS1: Weight: 25.2g , Length 79.3mm x Width 16.2mm (bezel)
4Sevens Preon 1: Weight 15.3g (with keychain clip), Length 75.6mm x Width 14.0mm (bezel)
4Sevens Preon ReVo:: Weight: 11.3g , Length 72.7mm (battery installed) x Width 12.9mm
ITP EOS A3 Upgraded: Weight: 11.6g (no clip), Length: 69.7 x Width 14.1mm (bezel)
ITP H01: Weight: 22.7g, Length 53.7mm x Width 37.2 (max body) or 15.4mm (bezel)
EagleTac PN20α: Weight 22.9g (with pocket clip), Length 80.1mm x Width 16.0mm (bezel), 18.6mm (max, around base)
LiteFlux LF2XT: Weight: 21.2g (with pocket clip). Length 81.2mm x Width 14.9mm (bezel widest portion)
Lumapower Avenger GX: Weight: 22.9g (with Clicky switch), 22.0g (with twisty switch), Length 93.8mm (with clicky switch) or 86.7mm (with twisty switch) x Width 15.2mm (bezel widest portion)
Maratac 1xAAA: Weight: 10.9g , Length: 67.5mm x Width: 14.1mm (bezel)
Tiablo E3A: Weight: 18.3g, Length 87.5mm x Width 14.8mm (bezel)
Titanium Innovations IlluminaTi: Weight 23.5g (with keychain clip), Length 68.8mm x Width 14.0mm (bezel)
VersaTi: Weight: 23.2g (no clip), Length: 67.1mm, Width: 14.6mm

The ReVO is one of the smallest 1xAAA lights I've seen. oo: Style is reminiscent of the old JetBeam Jet-u.

In keeping with its twisty status, screw threads are anodized for lock-out (i.e. tighten to turn on).

Light can tailstand (barely ).

Lettering is sharp and clear, in a muted gray-white against the black matte finish (type III hard anodizing). No chips or flaws on my sample. There is some reasonably good knurling on the body, and some fluted ridges on the head, to help with grip. Light can be operated one-handed.

4Sevens went with the XP-E emitter (R2 output bin) for this light, in a fairly deep OP reflector. I think this was a good call (scroll down to the end for a discussion)

And now for the requisite white wall hunting . All lights are on Hi on Sanyo Eneloop AAA, about ~0.5 meter from a white wall.

Sorry for the quality of the white wall beamshots – I've recently moved, and haven't had a chance to set up a proper beamshot closet yet. What you are looking at below is recently primed drywall.

As you can see, the ReVO has a more "typical" beam profile for a 1xAAA light (i.e. not as wide a spillbeam as the Preon 1). The hotspot is broad and diffuse, with a smooth transition from spot to spill.

User Interface

Turn on the ReVO by fully tightening the bezel. The light is off when the bezel is loosened.

Light comes on in Lo output to start. To select a different level, turn the ReVO off and then back on again within 1 second. This will advance to the next level of constant output in the following sequence: Lo -> Med -> Hi.

If the light is left off for ~2 secs or longer, it will revert back to Lo.

Like the others in the Preon series, the ReVO has 3 special output modes (Strobe, SOS, and Beacon). To access these modes, ensure the ReVO has been off for at least 2 seconds, then quickly switch through two full 'cycles' of the regular outputs. The two full cycles must be completed within 2 seconds, as follows:

Low -> Medium -> High -> Low -> Medium -> High -> Special Outputs

Once in the Special Outputs, you cycle through them with the regular twist off-on in the following sequence:

Strobe -> S.O.S. -> Beacon

After Beacon mode, the output automatically reverts back to regular Lo. You would need to the 7-twist switching to get back to Strobe.

Note that the SOS and Beacon modes are a little unusual. The SOS keeps the light on in Lo at all times, and "jumps" up in output to Max for the flashes. The Beacon mode flashes 5 times in increasing output, then stays in constant output on Lo with a single flash every 10 secs.

Note also that the ReVO has a "smart" Hi mode that steps down ~20% in output after a few minutes (to extend runtime).

PWM and Strobe

I couldn't detect any signs of PWM on the Lo/Med modes.

Strobe freq measured at 8.8 Hz.

Testing Method: All my output numbers are relative for my home-made light box setup, a la Quickbeam's flashlightreviews.com method. You can directly compare all my relative output values from different reviews - i.e. an output value of "10" in one graph is the same as "10" in another. All runtimes are done under a cooling fan, except for the extended run Lo/Min modes (i.e. >12 hours) which are done without cooling.

Throw values are the square-root of lux measurements taken at 1 meter from the lens, using a light meter.

Throw/Output Summary Chart:

Output/Runtime Comparison:

Note the step-down that occur ~3mins into the Hi runs.

Potential Issues

Head twist designs always have the potential to be "battery crushers." However, the ReVO seems to have some sort of flexible negative terminal pole. Not sure how it works, but I note that it rattles if you don't have a battery installed.

The time allowed for entering the Special modes is bit short (i.e. 2 secs for 7 On twists). Also, if you miss the mode you want, you have to start all over again, as you automatically exit back to regular modes after Beacon mode.

The SOS and beacon modes are unusual, with constant Lo output instead of shutting off between flashes.

Light cannot take 10440 Li-ion.

There is ~20% step-down in output that occurs ~3 mins into the Hi mode runs, as 4Sevens reports for this light.

Tailstanding is a bit iffy (i.e. wobbles easily).

Preliminary Observations

It seems clear to me that emitter output bin alone is a poor predictor of performance in the 1xAA class of lights – both for max output, and output/runtime efficiency. I've seen a number of XP-G R5-equipped lights that are no brighter than their earlier XR-E Q4/Q5 counterparts, and runtime efficiencies that are all over the map. Clearly, circuit design is pivotal in this class of flashlight – although I suspect other characteristics of the emitter (e.g. Vf) may also be critical.

The ReVO opts to use a XP-E with a R2 output bin – yet produces among the highest output and best overall output-runtime efficiency for this class of light. Well done!
The ReVO seems optimized for runtime performance – note the initial drop from Max output to ~80% after 3 mins. The light definitely seems to be current-controlled, given its excellent runtime performance and the lack of PWM. :thumbsup:

The build is excellent for this type of light – one of the smallest multi-mode 1xAAA light I've seen (just a hair under my old Jet-u in length and width). Mode switching is smooth, and I was able to do it one-handed (something I always found tricky with the regular Preons). And I like the look of the brass heatsink.

I also like the simple Lo – Med – Hi interface in regular mode (my preferred sequence). "Special" modes are well hidden. Actually, maybe a little too well hidden – I found it hard to consistently access Strobe. You need to do exactly 7 twists On in under 2 secs. :sweat: Miss your shot either way, over or under, and you have to start over (i.e. you can't cycle back to it in Special Output modes). That's a minor nitpick, since I can't see myself really using these too often, but I would think giving folks 3 or 4 secs would be better.

All said and done, this seems to be an excellent package for those looking for a miniscule 1xAAA for keychain carry.

----

ReVO was supplied by 4Sevens.com for review.

 

[regulator]

Great review as always. I was waiting for you to review this light. I think the Revo is an outstanding AAA light with top level efficiency but still plenty of features.

This is a light with a lot of inovation that is easy to overlook. It kinda sneeks by the radar as yet anothere AAA light. But its performance and construction are in a class of its own. Definately a light to get for the person who likes tiny AAA lights. I love the SS version. I might have to get another if they are offered again since I would hate it if I ever lost mine.

On the other hand, an aluminum version with a lithium Energizer has got to be so light and easy to carry - might need to get one of those.

 

[bodhran]

I've been looking foreward to your review on this light. A great job as always. Use mine all the time and with the Energizer Ultimate that was recomended, I'm still on the original battery.

 

[madmook]

Man I love those flat runtime lines... but I'll hold out for (hopefully) another SS run.

 

[GoneTomorrow]

First let me say hello to everyone. Secondly, I just picked up one of these and love it for a keychain light.

 

[lilbuj]

Great review. I am holding out for a Ti version to come out.

 

[alanjeep]

This might be some of your issues getting into the special modes. I was having the same problems.
The reply to the quote below is from 4sevens. this is from this thread https://www.candlepowerforums.com/threads/293115

Quote:
Originally Posted by paulr

Nice review, looks like an improvement over the original Preon and Quark Mini. Would be great if they just got rid of those blinky modes altogether

.

Without the blinky modes, a significant number of customers would not buy them. We did our homework

You forget the special modes are hidden away. In fact whats special about the Prevo is that once you stay on one of the three levels for 5 seconds or so, you'll never be able to get into the blinky modes without turning it off for 5 seconds. This further hides away the special modes used for special purposes. I've been around the flashlight market for a while and I have to say this UI is my favorite given it's versatility. Not to mention being proud of it since it was cooked up by our company
__________________

 

[Bass]

Excellent review Selfbuilt. Thanks for all hard work :thumbsup:

I have a SS ReVo and am delighted with it. A 4Sevens classic IMO.

 

[Toohotruk]

Great review! :thumbsup:

 

[selfbuilt]

I see there is a lot of interest on this one (compared to the other 3 1xAAA reviews I posted today ). Thanks for support everyone.

It kinda sneeks by the radar as yet anothere AAA light. But its performance and construction are in a class of its own. Definately a light to get for the person who likes tiny AAA lights.

Yes, when I saw it, it definitely brought to mind my old Jet-u. In fact, I just had to dust it off to include in the "usual suspects" mug shot. As you can see, that light did a lot of duty on my keychain - I'm a fan of this thin form-factor for 1xAAA. The ReVo is even a touch thinner, which is impressive.

This might be some of your issues getting into the special modes. I was having the same problems.

Yes, the intent clearly seems to be to make it harder to get into the special modes, and easier to exit.

 

[Minjin]

Looks like a great circuit with good output/runtime performance, but I wonder why he didn't go with an XPG which should improve both? Perhaps he's holding off for a special upgrade version. I like the idea to drop the high down after 5 minutes. However, I definitely don't like how difficult it is to get to the special modes and why the special modes themselves seem to be so non-standard. Innovation and being different is great but not to the point that it kills usability.

I don't care for the lack of real tail standing. He seems to borrow a lot of ideas from his business partner Fenix (nothing wrong with that) and I wish he would have borrowed the E01 tail design. Only other thing I see that worries me is the weight. To get that weight with a brass heatsink means that that battery tube is barely there. You can also see how shallow the knurling is. I hope it holds up. The Arc AAA always seemed like it had a fragile battery tube but it ended up being fairly durable.

Looks like a great keychain light though I still think the iTP EOS A3 is the bang/buck leader at less than half the price. :nana:

Great review as always.

 

[Mr Floppy]

I see there is a lot of interest on this one (compared to the other 3 1xAAA reviews I posted today ).

Yeah, those flat green lines are great. It's a winner for me with the alkaline regulation. I would like to see how the circuit performs with an XP-G. Preferably I would want a XP-G in this but it's not a big deciding factor. Tailstanding would be nice. A little disappointed that they couldn't do something better with that. Again sequence for modes is overly complicated so it makes it hard for me to get this as a light for non-flashaholics.

I too am a bit worried about weight. It's a bit lighter than the ITP upgrade. I have the single mode ITP and the tube was damaged after falling from my pocket when I was on my bike so I hope this one has some strength to it.

 

[hello_frank]

Good keychain light

 

[bltkmt]

Great review, as always...much appreciated! I have the SS version in my pocket daily...great little light that I know will run for a long time.

 

[selfbuilt]

Looks like a great circuit with good output/runtime performance, but I wonder why he didn't go with an XPG which should improve both?

I would like to see how the circuit performs with an XP-G. Preferably I would want a XP-G in this but it's not a big deciding factor.

According to 4Sevens's comparison chart for this light vs the regular Preon 1, the reason for the XP-E in the ReVO is the smaller reflector. :shrug:

But I'm beginning to wonder if other characteristics of the XP-Es (e.g. typical Vfs?) aren't better for suited for these sorts of lights. :thinking: Hard to know since the circuit is also quite different (i.e. fully current-controlled now). I suppose an industrious soul could try modding a ReVO light to directly compare XP-E vs XP-G ... but that won't be me. I've hung up my soldering iron - just no time (and I was never that good at it anyway). :nana:

However, I definitely don't like how difficult it is to get to the special modes and why the special modes themselves seem to be so non-standard. Innovation and being different is great but not to the point that it kills usability.

Again sequence for modes is overly complicated so it makes it hard for me to get this as a light for non-flashaholics.

True, but I doubt most non-flashaholics would care for the special modes anyway. :shrug:

I admit, I find it kind of odd that they've done it this way ... but I can't seriously see myself using these modes on a 1xAAA light anyway.

I don't care for the lack of real tail standing.

With you there - basically, all the light needs is a little extra something built up on one side, in a "T" shape (i.e. something more tripod-like). The Jet-u and Versa-TI both had something like that.

 

[rayman]

Got my SS one yesterday and I have to say that I really like it. It's just such a nice small light. Like the UI and the size and output is amazing. Likely I got a SS version.

rayman

 

[shigeru]

I have had my SS Revo for several weeks now on my keychain. It is a great little light. Aweome review!

 

[Prow]

Another great review, thanks selfbuilt. :thumbsup:

I've been looking for an upgrade to my Fenix E01 and briefly considered the iTP A3, but I don't like the rather low PWM (though I think I read there is an updated version now).

Anyway, along comes the ReVO and so I held off on the purchase to decide if I should spend a little more on a nicer light. This is the review I have been waiting for and those graphs speak for themselves as this light has great performance on all modes and types of batteries.

I know the SS ReVO has been getting a lot of love but I really like the look of the black ReVO and I'm quite sure it will be my first 4Sevens light.

 

[Photon]

I love this light.

Never heard of the Preon, let alone Preon ReVO, until I saw one at a show this afternoon.

Wasn't going to buy another flashlight since I already have have dozens (what flashaholic doesn't?), but when I saw it and tried it, well... flashaholics will understand.

They had a Fenix LD01 which I tried first. I am not a big fan of PWM (although I really don't know why), so every flashlight I test, I put it into low mode, hold my gaze steady at some arbitrary spot, then move the flashlight rapidly back and forth. Some lights have a very noticeable on/off pattern when tested this way. The Fenix has a much higher PWM frequency, but it too showed the telltale on/off pattern, although much closer together than any of the other lights.

So I tried the Preon ReVO light on low. No detectable PWM at all. Excellent.

The low is a nice low-low, perfect for dark-adapted eyes. The medium is pretty much the same as the Arc AAA, my EDC for many years, but with an even white light (no bluish tint). The high is outstanding for a AAA light.

Many think brighter is better; understandable. Personally, the Arc AAA is actually too bright to dark-adapted eyes. For this reason I have also been carrying a Mako Ti AAA because it has a nice low output. (Although it occurred to me later that I can always throttle the output of the Arc AAA with a finger over it.)

Now we have something for everyone in one package. This thing is a winner.

Bonus question: Does anyone know the etymology (word origin) of "4Sevens"? Just curious.

There. I feel better now. Thanks for listening.

 

[Crenshaw]

OOOoooo...

i like VERY much that its almost the same size as the Jet-U

I love the size of the jet-u, just never really liked the beamtype or the modes.

Now to find some money for this....

Crenshaw