Using 2865 Hz sound to clear water from a phone Speaker

[sam.in.a.box]

I came across something interesting recently, people using a 2865 Hz tone to help push water out of their phone's speaker after it gets wet. The idea is that the sound frequency vibrates the diaphragm enough to force droplets out, kind of like how some smartwatches have a built in water eject feature.

From a circuits/audio perspective, is there anything special about 2865 Hz that makes it particularly effective, because personally I dont see the science or would a range of frequencies do the same thing?

 

[snookyy5]

Well there's nothing inherently special about 2865 Hz, it just happens to sit in a range where many phone speakers can produce enough vibration to move water without distorting too badly. In reality, a range of frequencies could work since its about shaking the droplets loose, not a magic number. Some devices even sweep through frequencies to maximize the effect, so its more about what the speaker can handle than one exact tone.

 

[francsxz39]

I came across something interesting recently, people using a 2865 Hz tone to help push water out of their phone's speaker after it gets wet. The idea is that the sound frequency vibrates the diaphragm enough to force droplets out, kind of like how some smartwatches have a built in water eject feature.

From a circuits/audio perspective, is there anything special about 2865 Hz that makes it particularly effective, because personally I dont see the science or would a range of frequencies do the same thing?

Hey, cool observation! @snookyy5 is right, 2865 Hz figure isn't some magic number from an audio or circuits perspective. The core principle is to make the speaker's diaphragm vibrate with enough amplitude to physically shake the water droplets loose. The frequency used is likely close to the mechanical resonant frequency of the specific speaker being used. So while a range of frequencies would technically work, a tone close to the speaker's resonant frequency, like 2865 Hz for some models, would be most effective!

 

[jetHrow]

A steady, loud sound between 1 and 4 kHz will get that speaker cone moving and shake off those water drops. It's about keeping the volume up, not finding some secret frequency.