Looking at a spectrogram, I noticed these weird "harmonics" near 23-24 kHz (the light U shaped waves near the top of the picture, slightly ascending)...
Usually harmonics are just the same wave form at 2, 3, 4 x the base frequency, but here they are a mirror shape of the slightly descending base sound near 12-13 kHz...
I wonder how to explain that?
Usually harmonics are just the same wave form at 2, 3, 4 x the base frequency, but here they are a mirror shape of the slightly descending base sound near 12-13 kHz...
I wonder how to explain that?
