Strange pulsing sound .

[Rusty2]

Howdy .
I was recording the dawn chorus in the forest yesterday at 4:45am . While recording and after about 20 minutes this pulsing noise appeared .
The strange thing about it was that it got stronger and stronger and then suddenly stopped . It really started resonating in my ears and for a very brief moment I thought I was going to lose my balance . Then it just stopped .

Here's the audio file .

Pulsing.mp3

[Dion]

Interesting sound, I am sure the recording doesn't do it justice. I dont have any explanation but I do have a few theories.

[Rusty2]

Hi Dion . The recording sounds a lot higher in pitch (like a wonga pigeon) but if you hear it with headphones there's a more dominating lower frequency .
The file says it was coming more from the left but I couldn't tell where it was coming from .

I dont have any explanation but I do have a few theories.

I've heard the theories too but never heard anyone mention or record an associated noise , just the feelings of disorientation etc .

[P. Fields]

The recorded tone sounds a bit like a 'singing bowl' to me. Would've been a very strange thing to hear in the bush at dawn, especially if it was loud enough to mess with your sense of balance. The wavering/oscillating quality of the sound at a high volume would be pretty unsettling i imagine. A bit like loud microphone feedback at a concert. Very interesting!