Listen the hidden sounds
What if I tell you there are hidden sounds that you can simply listen and records. Disclaimer : it may be disapointing.
I love the idea of a terra incognita, the fact that you can easily reveal something hidden, something present but we can't see or hear it. As humans, we can hear sounds from 20hz to 20khz, witch is more than enough for doing human stuff. Some people can hear below and above, but still in that 10 octaves range. Sadly nobody can here 12 or more octaves. Even worse, I for instance, got great difficulty to hear above 10khz, I can hear but the sound must be louder, I feel the sounds rather than clerly hear it. 10khz! That's half of the spectrum! Actualy no, it's just the last octave (more on that maybe another time). Of course it depends of the nature of the sounds, and remember that's a sounds is rarely just one frequence. And that's what this article is about : a sound (eg. a voice, a singing bird, a motor, an instrument, etc...) is a complex variety of a great number of sound waves mixing together that makes it unique. This is why a guitar and piano playing the same note don't sound the same, each is a sum of different set of sound waves. And those set of sound waves (a sound) don't necessarily begin at 20hz or stop at 20khz, just for us to hear it, but often get way higher, above 20khz. And this is where the magic happen. We often hear the sounds of something in part, some objects continue to make sounds above -or below- our hearing ability. And the great news, it's that even a cheap recorder (like my trusty Zoom H1n) records sounds above 20khz. All this information that's we can't have acces is here, on a wave file, hidden and waiting to be discover. So what's the magic trick ? Simple, let's assume there is a sound around 30khz, recorded on your wave file. You just need to slow down by 4 (less or even more) times, and the sound that was originaly around 30khz is now around 7500hz. And voilà, your stupid human hears can get acces to it. Ok, now you might hate me or just figure it out by yourself a long time ago. But anyway, I really believe in the poetic charm of a sound discovered or rediscovered by this simple trick, the idea that there is more to be listen within the sounds we already know. Let's here some examples