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Princeton Tec Quad LED Headlamp REVIEW

Waterproof, four-LED headlamp with a wide, regulated beam.

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by Rick Dreher | 2006-12-05 03:00:00-07

Princeton Tec Quad LED Headlamp REVIEW - 1


Following its justly popular EOS, Princeton Tec offers the four-LED Quad in a very similar package. The Quad’s wide beam is very useful in camp and still supports nighttime travel. The Quad is light, affordable, waterproof and has an easy-to-use power switch. The Quad’s current regulation offers extended periods of steady output in the low and medium modes, but not in high mode.

What’s Good

  • Bright, wide beam that’s the best of any 5 mm headlamp we’ve tested
  • Waterproof to 1 meter
  • Easy-to-use power switch
  • Low battery indicator
  • Tilting lamphead
  • Light and compact
  • Solid build and materials
  • Affordable
  • Lifetime warranty

What’s Not So Good

  • Current regulation not effective on high
  • Beam exhibits the familiar purple artifacts typical of white 5 mm LEDs
  • Loose tilt ratchet on our sample



Princeton Tec


2006 Quad


Four, 5 mm LED headlamp with integrated battery pack


Measured: 3.4 oz (96 g) with alkaline batteries
Manufacturer’s specification: 96 g with alkaline batteries

  Batteries/Operating Voltage

Three AAA alkaline, lithium or NiMH/4.5 V




Yes (1 m)




High, medium, low, flash


Tilting lamp housing, low battery indicator

  Manufacturer’s Battery Life Claims

50 / 70 / 100 hours usage in hi/med/low modes

  Manufacturer’s Beam Distance Claims

29 / 18 / 12 m (95 / 59 /39 ft) beam range with fresh batteries in hi/med/low modes


Lifetime US, 10-year international




The Princeton Tec Quad demonstrates the continued viability of multi-5 mm headlamps in a marketplace being quickly dominated by high-output 1-, 3- and even 5-watt Luxeon LED headlamps. The Quad is surprisingly bright for a small, four-LED headlamp and casts a relatively wide and even beam. This is good news for those who don’t care for blazingly bright pencil beams that illuminate a trail 100 feet ahead but aren’t so nice on the eyes in camp. The Quad is small, light, waterproof, frugal and features regulation for extended stretches of steady output.

Compared To

The Quad is a close cousin to the 1-watt Luxeon EOS, a light we’ve extolled at Backpacking Light for its stellar performance, light weight and affordability. We’ve also been fans of the Princeton Tec Aurora in the past, but it’s astonishing how superior the Quad is to the Aurora for small increases in weight and cost. Several recently upgraded Petzl 5 mm LED headlamps compete with the Quad, including the Tactikka that features a night-vision preserving flip-down red lens. None of the Petzl lights match the Quad’s regulation and waterproofness rating. Black Diamond’s Cosmo is their closest equivalent, and it also lacks regulation and immersibility.

Princeton Tec Quad LED Headlamp REVIEW - 2
The Princeton Tec Quad houses its four-LED array behind a protective lens.

Design and Construction

Controls and Operation

The lone combination power-mode button is located atop the Quad’s lamphead. This large button is operable wearing heavy gloves and mittens, and is the best we’ve yet used. Controls follow the typical high, medium, low, flash, off operating sequence. No mode memory on power-up means the Quad always starts on high, a trend we’d like to see eliminated on all flashlights (either start on low or the last mode used). A 1.5-second pause in any mode means the next push turns the light off, eliminating the need to roll through all the modes.

Princeton Tec Quad LED Headlamp REVIEW - 3
One easy-to-use button atop the Quad controls power and mode, and can be operated even wearing mittens.


The Quad’s LEDs are arrayed four-across behind a protective lens. The lamphead’s eyebrow shape reduces glare and backscatter. Its angle adjusts from straight ahead to a downward tilt of ninety degrees. Upward tilt from horizontal isn’t possible, but as with any single-band headlamp, invert the Quad if an upward tilt is needed. Our sample has a rather loose ratchet, meaning the angle can be knocked from the set position. (This could be sample variation, as store copies I’ve checked have stiffer and more reliable ratcheting, but potential buyers have no way to check out a packaged sample in the store beforehand.)

Battery Power Meter

When the batteries are nearly dead, a red LED battery indicator a little below the LED array blinks when the light’s off. Also, the main LEDs will blink upon switching on a Quad with very worn batteries.

Battery Compartment

The hinged battery compartment is integrated to the Quad’s lamphead. It’s o-ring-sealed and held closed by a captive, slotted and knurled thumbscrew. The headband buckle serves as a screwdriver for opening and tightening. Batteries access is easy and correct battery alignment is obvious - a safety feature for the headlamp itself. Batteries are secured tightly enough that they’re unlikely to fall out inadvertently. Princeton Tec claims IPX7 water resistance for the Quad - immersible to 1 meter for 30 minutes. Our dunk test confirms this spec.

Princeton Tec Quad LED Headlamp REVIEW - 4
The Quad’s easy-access battery compartment.

Princeton Tec Quad LED Headlamp REVIEW - 5
Slotted strap guides allow easy removal and replacement.


The simple 1-inch wide headband is soft and comfortable. It’s long enough to fit a climbing helmet and the strap guides are notched for easy removal and replacement, making it easy to wash the strap if so desired.


I measured beam intensity and width at all output levels from our standard 2-foot distance. Effective beam control tames the four white LEDs into a wide and even beam with a good amount of beam “spill” for peripheral lighting. The beam center has the familiar purple tint generated by seemingly all white 5 mm LEDs, but not so pronounced and annoying as with many earlier lights. The LEDs are a big improvement over their predecessors, both in brightness and color quality, and likely represent the latest evolutionary wave from the electronics wizards. It’s not possible to ascertain whether the Quad’s reflector-like bezel has a positive effect on the beam pattern, although I suspect it’s likely.

Beam Center1 ft off-axis
In Lux, with fresh batteries, measured from 2 Feet

With fresh batteries the Quad is very bright for a four x 5 mm LED headlamp. As a point of comparison, our test Princeton Tec Corona isn’t as bright with eight LEDs. The Quad’s initial high mode output was 630 lux. There’s an ovoid center spot - purplish in hue - that averages about 8 inches in diameter at 2 feet distance. Rather than a sharp cutoff at the bright spot’s edge there’s a gradual transition to a much larger and somewhat whiter area, perhaps 18 inches in diameter. In sum, the Quad provides a very wide and useful beam pattern.

Our experience is that low and medium are satisfactory for all camping and a certain portion of trail activities, and high supports nighttime navigation of fairly sketchy trails. The relatively wide and even beam illuminates a wider swath of the trail than a typical Luxeon light. This is sometimes preferable, for example, if you’re following a path and looking for blazes.

I performed run-time tests on the Quad in high and medium modes. Review of the graph reveals my biggest Quad qualm: there’s not much evidence of effective regulation in high mode. Intensity dropped by about a third in the first fifteen minutes, then by half from that point over the next four hours. It reached the initial medium equivalent at about four hours and initial low equivalent at nine.

Medium, by contrast, shows effective regulation - providing very steady output for almost eight hours, then a gradual decline for several hours more. Medium crossed the initial low equivalent at about twelve hours, and eventually matched the high output curve at about twenty-four hours.

Princeton Tec Quad LED Headlamp REVIEW - 6
Tests run at room temperature (68 deg F) with alkaline batteries from a single batch.
Click graph to enlarge.

Princeton Tec advises that the battery power meter activates when batteries are near the end of their functional life. Our tests seemed to verify this, as the signal first appeared near the end of each battery run at roughly 30 lux (about 5% of maximum brightness). The miniscule red LED blinks only when the light’s switched off, and seems primarily aimed at the grab-and-run crowd who wouldn’t bother to check their flashlight before taking off with it. Additionally, the Quad switched on with nearly dead batteries blinks the main lights several times to alert the user of their status (in case the very dim output isn’t evidence enough). This occurred well after the red signal first activated in our tests.

In the Field

The Quad proved effective and comfortable in varied nighttime situations. In camp it’s an ideal headlamp - the bright, wide, smooth beam is great for setting up, cooking, organizing, or hanging a bear line. Most of the time, the low setting serves up enough light. As a trail light the Quad might even be better than a brighter pencil beam on easy trails by lighting up more of the border and reducing the need for head swiveling. Even with the wider beam spread it’s still effective for sketchier paths. Of course, sometimes there’s no substitute for “horsepower” and focused 1 and 3-watt Luxeon lights are simply better, but perhaps my biggest surprise with the Quad was that those times are less common than I’d expected. I suspect this is mostly due to the Quad’s being far brighter than other 5 mm lights I’ve used, combined with its well controlled beam pattern and more neutral color.

The lamphead extends far enough to reduce glare off of glasses. The strap is comfortable and holds without cinching it tight, so it can be worn for hours if necessary. The angle ratchet doesn’t hold as well as I’d like and as noted earlier, might be defective on ours. While not a balanced designed with batteries in back, the Quad is sufficiently light that it doesn’t seem front-heavy. Of course, no batteries in back make it great for reading while lying on one’s back.

Batteries, and Realistic Run Times

Three AAA alkaline batteries provide good life at 35 grams per set, while a 23-gram set of lithiums will last longer and significantly boost cold-weather performance. It’s certainly the case that with prudent use, the Quad can provide many, many nights of service on a single set. Use our runtime chart as a rough guide for projecting your likely use. Even when the batteries are all but dead they’ll continue for hours, perhaps days longer at a very low level. At a measly 10 lux there’s enough light to dig items out of a pack or even cook, but not enough light for nighttime travel, at least for those of us not blessed with owl eyes.


The Quad almost single-handedly reinvigorates the multi-5 mm LED headlamp marketplace, giving those who don’t like 1-watt Luxeon headlamps a legitimate 5 mm alternative for technical nighttime travel. Most similar headlamps are, generally speaking, suited only for walking on clearly delineated trails; however they, like the Quad, are superior to most Luxeon-only headlamps for camp chores and reading.

Clearly based on the EOS, the Quad’s general design and construction are also simple, robust and now proven. In fact, the Quad power switch is better than that on the EOS. Like the EOS, the Quad is compact and lightweight, making it a pleasure to carry and wear. Since a single battery set can last a good many trail days, most users will be freed from carrying spares.


At $30 the Quad is a very good value. It’s aggressively priced in a very competitive market segment, while providing a unique feature set and packing Princeton Tec’s reputation and lifetime warranty.

What’s Unique

Very bright for a 5 mm headlamp. Effective regulation on medium and low. Great switch. Immersible.

Recommendations for Improvement

Effective regulation in high mode would improve the Quad, even if it came at the cost of lowering initial output some (there’s little benefit to gaudy output that lasts five minutes). Reverse the mode sequence to begin on low or provide mode memory. Incorporating an always on “find me” feature to the power meter, similar to Black Diamond’s Zenix IQ, would extend its value, as would a two-stage power warning (e.g., stage 1 at 50%, stage 2 at 10%). We’re presuming our sample’s loose ratchet is an anomaly, and not representative of most Quads.


"Princeton Tec Quad LED Headlamp REVIEW," by Rick Dreher. (ISSN 1537-0364)., 2006-12-05 03:00:00-07.


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Princeton Tec Quad LED Headlamp REVIEW
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Benjamin Smith
(bugbomb) - F - M

Locale: South Texas
Princeton Tec Quad LED Headlamp REVIEW on 12/05/2006 20:47:55 MST Print View

Companion forum thread to:

Princeton Tec Quad LED Headlamp REVIEW

paul johnson
(pj) - F

Locale: LazyBoy in my Den - miss the forest
Re: Princeton Tec Quad LED Headlamp REVIEW on 12/06/2006 05:54:45 MST Print View

IMHO, this is really an excellent headlamp, just as Rick's Review states.

I'd like to see a "shootout" b/t the Quad vs. '06 (or newer) ZipkaPlus, using the upgraded 80% brighter LEDs (or substitute '06 TikkaPlus or '06 TacTikkaPlus for the ZipkaPlus).

Let's see [5min or 15min]PLOTTED periodic LUX meter readings for both headlamps on HI, MED, and LO output so that we can see if there is any real benefit to current regulation. To ease the "pain", so to speak, on the Tester, maybe only every 30min or 60min data points for the LO output mode "run"/test, as this will be a long test.

One picture/plot is worth a thousand words.

Also, some indication to see if the quantitative numbers result in a perceivable difference. Summarize periodic qualitative visual observations of brightness, observed at the same time as the lux meter readings, using a Data Table with three indications, e.g.,
NPD=no perceivable diff in brightness when this datapoint taken,
SPD=slight perceivable diff, and
DPD=definitely a perceivable diff

A simple Data Table would suffice to summarize this info which would necessitate a SIDExSIDE comparison test.

I prefer the Petzl ZipkaPlus however for two reasons:

1) my '06 ZipkaPlus (w/the upgraded 80% brighter LEDs) is just a tad brighter (perceived, NOT meas. w/a lux meter) than my PTQuad using fresh batts in both and all batts having starting voltages w/i 0.01 volts of each other.

Side by side, the difference is small, but perceptible.

Admittedly, this may be JUST MY TWO PARTICULAR UNITS. I'm NOT sure how well PT and/or Petzl try to select for brightness and match their 5mm LEDs. Another two units, one from each Mfr, could possibly have the exact opposite comparative brightness.

2) I'm really hooked on the Zipka "form factor". It's just so easy to carry one in my pocket even to work. I'd like to see a Quad with a somewhat similar "headband" which doesn't violate any current Petzl Patents. Since the housing might have room in it, or possibly could with slight modifications accomodate a retractable "reel" type of headband similar to the Zipka; or, perhaps better yet, leave the hinged bracket; make it slightly thicker; and place the retractable reel mechanism in it. The back of the two-piece bracket would be the portion that is placed behind the head with the cord-headband being reeled out from and into the thicker two-piece bracket. This would retain the tilt adjustablility feature lacking in (and sometimes complained about by others - though my bald head has no problem accomodating different position for the Zipka) the Zipka/ZipkaPlus headlamps. Who knows, just might work???

I'd also like to see (if it makes sense from a performance standpoint, b/c it doesn't work from a cost standpoint, IINM [if i'm not mistaken]), a 2xCR123 PTQuad "Pro" (similar to the new PTApex Pro).

Two CR123 cells in series have, IINM, nearly the stored energy of 3 AAA cells, but have a higher starting voltage. This should(???) enable current regulation mode to last longer in the Quad which might be preferable for some users. Two axially aligned CR123 batts have a nice form factor (take a look at the Streamlight Argo HP headlamp) that would fit nicely under a Quad, or perhaps they can be "shoe-horned" inside of a slightly redesigned current Quad case (similar to the older eGear 1W Luxeon headlamp using 2xCR123 batts, not similar to the newer eGear 3xAA 1W luxeon headlmap, or newer eGear 3xAAA 1W luxeon headlamp).

Weight of this proposed Quad "Pro" (w/o the "zip" retractable reel headcord arrangment) would prob. be just a little heavier due to batt weights, depending upon whether alkaline or Li AAA batts were used.

3xAAA Li batts = ~0.81oz
2xCR123 Li batts = ~1.18oz
3xAAA alkaline batts = ~1.20oz

Due to the lower current draw (even on HI output) of the proposed Quad "Pro" vs. the Apex Pro, the use of CR123 batts, might produce longer regulated times in a Quad Pro than they do in the new Apex Pro (no cp. b/t stored energy in 4xAA batts vs. 2xCR123 batts and the 4xAA batts also start nominally at 6VDC). In most regulator designs i've encountered over the years, constant current regulation depends upon the supply voltage to the regulator remaining above a certain level in order to adequately power the regulator. So, this would make 2xCR123 batts at a nominal 6v rating possibly produce a real benefit when used instead of 3xAAA batts at a nominal 4.5v rating. Since the stored energy in both is somewhat similar, depending upon regulator design, this might really work - at the greater expense of CR123 batts. BTW, i've found them for 12 for $18.95 and 12 for $21.95. Also, i've started using rechargeable Li CR123 cells in some headlamps. They work well, but when they run down, the LED very suddenly (nearly in an instant) stops produces anything but a dull glow (i've tried this in an Apex Pro).

Just another thought.

Edited by pj on 12/06/2006 06:27:37 MST.

Mike Clelland
(mikeclelland) - MLife

Locale: The Tetons (via Idaho)
Princeton Tec Quad LED Headlamp on 12/06/2006 11:23:56 MST Print View


I've used lithium batteries in the winter (in my Petzl TIKKA-plus), and they seem to perform better - and it's lighter. But, Petzl claims that LITHIUM batteries can damage their headlamps.

Is there any recommendation by princeton NOT to use LITHIUM batteries?

If Princeton say it's okay to use LITHIUM batteries, that would be a huge advantage, and it would make their product very desirable to me. Is it okay?

Rick Dreher
(halfturbo) - MLife

Locale: Northernish California
Re: Princeton Tec on lithium cells on 12/06/2006 11:45:19 MST Print View

Hi Mike,

PT is very direct on the use of Li cells:

"Weight conscious users will love the Quad's sophisticated circuitry that allows the use of lithium AAA batteries."

Regulation performs at least two functions: it compensates for decreasing battery output AND it attenuates high battery output, which can occur with fresh Li cells. Voltage spikes can damage LEDs, which I'm guessing is what's happened with the Petzl lights.

Rick Dreher
(halfturbo) - MLife

Locale: Northernish California
Re: Princeton Tec Quad LED Headlamp REVIEW on 12/06/2006 11:51:16 MST Print View

Thanks for your comments Paul. I'm hoping to get my hands on a four-LED Petzl light so as to make the comparison, because I too am interested in how they match up. But for now, the Quad snags the title in the class.

I see a lot of potential in compact CR123-powered lights, and wonder whether the Apex Pro experiment is a test of the waters by PT. I think a major limitation of the form is that cheap cells aren't available in stores, just on line.

More test reports to come in the new year, including one you've been patiently awaiting ;-)

paul johnson
(pj) - F

Locale: LazyBoy in my Den - miss the forest
Re: Re: Princeton Tec Quad LED Headlamp REVIEW on 12/07/2006 03:55:16 MST Print View

Rick, PM me please. I think you can figure out why. It's for the same purpose as the last time.

Also, Rick, i was away for awhile. Did i miss an Apex review from you? I was hoping to get burntime plots and an output table on the Apex.