speedlite 550ex

[pavel p]

I just received my 550EX and I think there is a problem. The flash

makes an intermittent hissing (high pitched) sound. It last barely a

second. Disappears. Reappears in a few seconds. After a flash, you can

hear it stronger and it fades away. I guess you can say its charging,

but:<br>

1)is it supposed to sound like that?<br>

2)why does the sound appear when its idle?

[rickvandenberg]

Flashes use a high-frequency oscillator to charge the flash capacitor - that's probably what you're hearing. All capacitors bleed off their charge (some faster than others) - it's called leakage. I can imagine that in your case the intermittent whine is simply the unit keeping the capacitor charged. I can't comment as to how loud it should be, but my Vivitar 285's are much louder than the 580ex I have.

[pete w]

Pavel, The sound is normal not to worry.

[jimstrutz]

People have been complaining about the sound of the 550EX from the day it was introduced. Same with the 540EZ before it. It's an awful noise. Not at all like the smooth squeel that most other flashes produce.

[gary_jean1]

I didn't know they were still selling 550EXs. Is it new?

 

What kind of batteries are you using? If you're using alkalines, the flash will be noisy as it struggles to charge and quickly kills the batteries.

 

Use NiMH or lithium batteries and the flash will be less noisy.

 

If you're already doing that, I don't know what to tell you. Both my 550EXs are very quiet, as compared to some older non-Canon units I have.