Princeton Tec Apex+++ (AKA Apex with XM-L)


Newly Enlightened
Feb 10, 2007
North Vancouver, BC, Canada
I bought a PT Apex a few years ago, with the luxeon LED. I later upgraded the LED to an SSC P4. Loved that. I named that the Apex+. Then in 2010 I made it the Apex++ by sticking in an XP-G warm white Q5. Today, it has become the Apex+++, containing a cool white XM-L T6.

- my XP-G had too tight a beam, but it could be because I burnt the dome slightly with my soldering iron, or the LED's height wasn't correct

- the XM-L produces a much broader beam than the XP-G; not sure if it's broader than the SSC P4 or stock Luxeon III but I think so

- my XP-G beam was ringy; the XM-L beam is too, but much farther out towards the periphery so I don't notice it at all in use. The main beam (can I call it a spot even if it uses a collimator, not a reflector?) is much bigger and more useful, like a headlamp should be.

- the XM-L tint is quite green

- because the XR-E's max current is 1A, I would assume that the SSC P4s max. current is also 1A, so I would assume that the driver is pushing 1A or less. At 1A or less, Ive read some peoples opinions that the XM-L should not produce much more output than an XP-G. I think I'm getting more output, but possibly because my XP-G is a warm-white Q5, and possibly because I burnt a spot on the XP-G's dome.

- because of the rings, I'm still not getting as much brightness as I should be. Some light is essentially lost to those rings.

- I used aviation snips to trim the star down to an approximate shape, then filed it to get it to fit into the plastic holder

- it wasnt easy to center the LED—youd have to file it symmetrically, which I didn't, so my beam is a little bit lopsided, but it's not noticeable at all in use.

- I filed the star just enough so that it was a tight fit inside the black plastic LED holder

- solder the LED before you put it on the heatsink, or the heatsink will make it tough to heat up the pads

- working with a regular-sized star was much easier to work with than the 10mm XP-G board, because the pads are way bigger and farther from the LED (see comment above about burning the dome!)

- I used my recently purchased desktop vise, and it helped a lot

- total mod time = 1.5 hrs, including some trial error. If I did it again, it would take an hour

- outdoors: wow, this thing lights up everything now. I don't remember what the Apex or Apex+ were like, but I do remember that their beams were quite wide and even, which I really liked. The Apex++ I didn't like much because of the narrowness of the beam and of course the ringiness. I had to move my head around too much. I think the Apex+++ has the widest beam of all, and it's excellent. It lights up the whole yard, and lights it up very evenly. It makes the Apex a great headlamp again.

Pics: (note: the wall is not white, so the colours aren't accurate, but the relative difference is a good indicator)

The Apex++ with XP-G warm white LED:

Apex+++ with XM-L cool white LED:


the vise I bought:


the LED after cutting and filing down the board: