Anyone else hear a high pitched whine from their fenix uc35 v2?

I just picked up a fenix uc35 v2 recently... great, BRIGHT little light. But on any of the medium three dimming levels, it emits a very high pitched whine like the old CRT TVs used to do, around 16KHz. I can hear it across the room, and it's pretty obnoxious. I emailed support and they said it wasn't normal and sent me a replacement, but the replacement does the same thing.

Seems unlikely that I'd get two bad units in a row, so I just wanted to see if anyone else owned one and if it makes the same noise?

I think it's called inductor whine. It's one of the components on the circuit board if I remember correctly. It's not uncommon in a variety of lights.

I've only heard it from one of my lights: a 4sevens Quark. It's annoying, but I don't think it causes any problems. My hearing isn't that great, though, so perhaps it's more common than I think (just higher in frequency).

I feel like I've had that before on lights, but so infrequently that I can't remember which one. And not loud like you are talking about. I think I thought I heard something once holding one up to my ear. But I definitely have experienced this with other electronics. I remember this with old CRT TVs. When I was younger I thought I had a superpower because I could hear that and my Dad couldn't haha.

On your UC35 V2 does this only happen on a certain mode? I have to say the new Fenix lights with brass buttons look so nice. Stinks to hear if inductor whine is a thing on certain lights. We'll have to see.

martinaee said:

On your UC35 V2 does this only happen on a certain mode?

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Yeah it's most noticeable in the middle 3 modes (out of 5). I wouldn't mind it so much if it was only when I hold it to my ear, but it's actually pretty loud.

I guess it's good to know my hearing is still good...

nbp said:

I think it's called inductor whine....

Click to expand...

Yep, or "coil noise" or "coil whine" or electromagnetically excited acoustic noise and vibration

Interesting, thanks. I'm vaguely familiar with the concept in other electronic devices but I own a bunch of Fenix lights and have had the issue before... :shrug:


I wish it didn't bother me so much. I love the light otherwise. Does anyone have any recommendations for similar lights from other brands that don't whine? Specifically something usb rechargeable and 1000+ lumen.

Does that light by chance use PWM on any modes? I wonder if that's at all related to the whine at all if so?

Potted electronics are less likely to "whine" and, yes, PWM can drive whine.

I have that exact light, but I haven't heard that from mine.

just ordered one i will let you know

My old Fenix TK 20 wines is so loud I can use it as a locator beacon. Some of my old HDS do this as well

I had a black and decker 4aa spotlight I bought at Wal-Mart years ago that whined like that. I did it in one mode but not the other, I can't remember if it was the high or low. Did it for the 5 or so years I had it with eneloops and I used it often until I gave it away.

So 'potted' electronics are less likely to -whine- huh, ok I'll bite-there wouldn't be a maker of led flashlights that pots their electronics would there?