whats this sound?

[tygger]

i have two LS seconds and i love them both. i just noticed that when i turn either of them on after a few seconds i can hear a very slight hissing/bubbling sound like air is being forced out from where the head connects to the body. it only lasts about 5 seconds or so. the lights work perfectly and i'm sure it's natural but i'm just curious as to what this sound is. is it because of the heat produced by the luxeon in the head forces colder air out? just curious.

 

[Gransee]

Since it is seconds instead of minutes before you hear the sound, it is probally not the LED or battery causing it. It is probally the air being compressed by screwing the two pieces together being forced out around the lens.

Peter

 

[tygger]

oh, that makes sense. thanks.

 

[d'mo]

Hmmm, I wouldn't think there would be enough air in the battery compartment to result in pressurization. We're only talking about a fraction of an inch of travel on the head threads.

I'd try it myself, but I'm waiting for my Arc-LSs to be delivered. Is there an o-ring that can be removed to test the 'pressurized air" theory? If it's removed, the hissing should be gone.

 

[The_LED_Museum]

I tried it with both of mine, and there's no hissing, bubbling, gurgling, flushing, or any other sound when they're tightened.

 

[txwest]

Put it in some water & see where the bubbles are comming from. TX

 

[Footlight]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Gransee:
Since it is seconds instead of minutes before you hear the sound...<HR></BLOCKQUOTE>This is why they are called LS Seconds. The ones with the longer lasting hiss are sold as LS Minutes

(sorry Peter, could not resist)

 

[flashfan]

Horrible, Footlight, horrible...but LOL, I love it!

 

[tygger]

god, if anyone saw me they'd think i had really lost it. not only have i been shining my LS at the wall all night for beam comparisons, now i'm LISTENING to them! "hello, hello, is anyone there?" anyway, peter was right, the sound is a result of pressurization, air being forced out where the lens connects to the head. it only happens when i remove the battery pack and then screw it back on. next thing you know i'll start doing scent comparisons.

 

[d'mo]

Tygger,

I just got my Arc-LSs and when installing some virtually dead 123 batteries, I hear the hissing, popping sound too. I've heard similar sounds examining cold-cathode fluorescent step-up transformers. I suspect something similar is happening when the charge-pump circuit has to work a little harder.