My L2 tailcap is buzzing faintly on low output!

I recently broke down and bought a SureFire L2, and while I like this light more than I thought I would, there is one small issue I've got with it: when low output is activated, the tailcap makes a faint buzzing sound. This only occurs for low output; with high output the tailcap is silent.

I vaguely remember reading about this sort of thing before... so could someone tell me why this is happening, if it is normal behavior, and if not, how to correct it?
/ubbthreads/images/graemlins/confused.gif

Also, while we're talking about the tailcap, is the L2 tailcap the same as the one on the L1 and A2 lights, or somehow different?

Mine does that too, and I think most buzz on low. I don't know the answer to your second question.

Yup, that's normal. The buzzing is very faint, though. I myself can only hear it when I place the tailcap right beside my ear. Then again, I might be older than you (i.e. worse hearing...)

Sorry, can't help you with the A2 tailcap.

its normal

i think all L2 does that

the buzzing actually bothered me a little bit, cause i usually held my flashlight in the palm and use the thumb for switch, so the flashlight is near/around my ear all the times

but anyway, don't worry, its normal /ubbthreads/images/graemlins/smile.gif

I think the humming is kind of cool. To my knowledge, the L2 tailcap is the same as the A2. I believe the humming is not coming from the tailcap, but from the circuitry in the "coffin" near the bezel. Unofficially, I think the humming also lets you know that the low mode is still in regulation. /ubbthreads/images/graemlins/cool.gif

leukos, you're correct! I always assumed it was the tailcap, since everyone just talked about it, but the humming is definitely louder at the head. Interesting...

My U2 does it as well as my L2.

Re: My L2 tailcap is buzzing faintly on low output

Take the bezel off the L2 and press the switch (both levels) and listen to the bezel-end of the body...

Al /ubbthreads/images/graemlins/smile.gif

P.S.
I wonder how long it'll take to drain the batteries without the bezel installed, and whether it'd be faster on low or high constant-on??

Re: My L2 tailcap is buzzing faintly on low output

what would that happen? /ubbthreads/images/graemlins/grin.gif

Re: My L2 tailcap is buzzing faintly on low output

Probably some kind of radiation leak... /ubbthreads/images/graemlins/eek.gif /ubbthreads/images/graemlins/eek.gif Nothng to worry about... /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

Re: My L2 tailcap is buzzing faintly on low output

probably the lithium batts leakin an fryin the internals but nothin to worry bout "if it breaks we fix it"

Re: My L2 tailcap is buzzing faintly on low output

At certain low levels, you can hear the inductors 'sing'. I think it happens to most of them, my U2 has it on level 1, and some of my BB sandwiches had it too when the batteries were low. It's normal.

Re: My L2 tailcap is buzzing faintly on low output

[ QUOTE ]
Size15's said:
Take the bezel off the L2 and press the switch (both levels) and listen to the bezel-end of the body...

Al /ubbthreads/images/graemlins/smile.gif



[/ QUOTE ]

interesting. i've always thought that it was from the tailcap to~
my U2 doesnt buz at all on any level. i guess i got a good pick~ /ubbthreads/images/graemlins/grin.gif

Re: My L2 tailcap is buzzing faintly on low output

My A2 sometimes buzzes when the batteries are full.
I have made a headband to use the A2 as a headlight and the first time I used it that way, I noticed it. A faint sound, but not irritating or annoing me.
the U2 never buzzes.

a bit of topic perhaps, but a red filter on the U2 seems to cut the amount of lumens about half.
My A2 with red leds gives the same amount of light as the U2 with red filter on the 3th setting.
Is this normal?

Re: My L2 tailcap is buzzing faintly on low output

[ QUOTE ]
AlecGold said:
a bit of topic perhaps, but a red filter on the U2 seems to cut the amount of lumens about half.
My A2 with red leds gives the same amount of light as the U2 with red filter on the 3th setting.
Is this normal?

[/ QUOTE ]
I think it's normal. Luxeons generally emit less light in the red portion of the spectrum. link to spectrum graph

Re: My L2 tailcap is buzzing faintly on low output

About buzzing...

I have two L2s, and both buzzes at low level. I come to the conclusion that both the tailcap AND the bezel makes that buzzing sound at low level. I suspect that in the tail cap there is an inductor. The noise is square-wave 800 Hz.

Now, the L1. Never buzzes, normally. Try to put in a 3.7 V Li-Ion 123: at low level it makes the light which intensity I just love, but at high level... it makes a so strong buzzing sound, but so intense and sinistrous that I terminated all tests with the L1...

Now, the Inova 24/7. White LED low setting, same problem...

The U2 seems to be very discrete at all levels.

Other lights, as Al suggested, may produce some other sounds, if used as seashells... without the bezel, and very close to the ear...

Anthony