My Running Headlamp: the Princeton Tec Eos

Last September, my old Princeton Tec Matrix’s battery compartment clip broke and the tilt adjustment wore out (would not stay up). While annoying, I hadn’t really ever used the Matrix for running. November came, and with it so did the early darkness of late fall nights. It was time to get a new headlamp. While I’d love to have a Princeton Tec Apex, it wasn’t within my price range, and is a little heavy to wear while running.

After some searching, I narrowed the field to two candidates, the Princeton Tec Remix and the Princeton Tec Eos. Both are LED based headlamps, the Remix has three low power “indicator” LEDs plus a 1W high power LED. The Eos has only the high power LED. While I would like to have the LED setup of the Remix, it has one fatal flaw. The Remix does not have a gasket seal, and thus it is not waterproof. As my previous two headlamps were waterproof, this single feature sold me on the Eos.

The Eos falls under the “professional” branch of Princeton Tec’s products. Members of the “professional series” are waterproof to IEC Level 2 (down to 1m). This means they all have a rubber o-ring, something none of the “the family” members such as the Remix have. Additionally, members of the “professional series” feature regulated output.

Unregulated lamps will be very bright when new batteries are installed, and they get dimmer as the batteries drain. Regulated lamps will hold a constant brightness until the energy left in the batteries can not sustain that brightness, then they dim until the circuitry cuts out. Typically, this is done using a switching regulator, and is something that my old Matrix had, and was something I wasn’t going to give up.

Speaking of battery life, I’ve ran with the Eos twice a week since the second week in November. Using the medium brightness setting, the included AAA batteries lasted through January. By lasted, I mean they powered the lamp so that the emitted light was useful on the sidewalk. The runs were anywhere from 45 minutes to 90 minutes, with the headlamp on the entire time. This equates to about 24 hours before being too dim.

Note that I have been running on a mix of sidewalks and trails with occasional street lights and headlights from traffic. There hasn’t been much snow, and we’ve had quite a bit of ice on the asphalt sidewalks. Both of these combined require more light to safely see what is going on. Trail running, away from street lights and traffic, with some snow cover, would only require the lowest brightness mode, which according to Princeton Tec, lasts 50 hours.

As with my previous two headlamps, Princeton Tec provides as set of Energizer batteries for the headlamp. While they both used AA batteries, the Eos uses 3 AAA batteries. Other than the batteries, the package includes the headlamp body, a head strap, usage instructions/warranty information, and a Princeton Tec sticker. No felt carrying/storage bag included, unlike my previous two lamps.

While overall I love this headlamp, the one thing that does bother me is the strap. It is a simple headband, without a over the head portion (the Apex has this, as did my previous two headlamps). This is not a problem most of the time, however I think it would provide more stability for the lamp while running. Since this winter has been quite warm, I have warn this over a hat, and without a hat. The slight difference in circumference is enough to require readjusting the band. Too tight and you get a headache, too loose and the light bounces up and down with your stride. Quite annoying if you ask me. Though, this is something you will see with all headlamps with a similar headband except for those that are much lighter.

-John Havlik

[end of transmission, stay tuned]


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3 thoughts on “My Running Headlamp: the Princeton Tec Eos

    • My old Matrix’s head strap could be a donor. Though, if I remember correctly, the way the Matrix connects to its strap is a bit different from how the Eos does it.

      -John Havlik

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