I get constructive and deconstructive, but those are usually in the context of being the same frequency and just being out of phase. I’m talking like…you and your bud having a conversation in a restaurant, with music playing, convos around you, sound of wait staff, etc. If a waiter drops a plate, how does that sound transit through at that higher, unique frequency through all the other noise so that all can hear it?
Thank you for your time!
In: Physics
Sounds are made up from complex waveforms and for it to cancel out it has to be an identical waveform inversed. For the sounds that you mentioned there definitely *will* be some frequencies cancelling eachother out but the complexity of the waveform of the sounds you mentioned keeps them from cancelling out. A soundwave also gets broken up and dispersed all the time.
You can make an experiment, if you have decent speaker, play a simple sine wave, since it has only the fundamental frequency and no overtones, at around 100hz or some then walk around the room back and forth from the speaker. Then note how at certain places in the room you cannot hear the sound (but you will be able to feel the pressure) and other places it will sound twice as loud. Now try this with a saw and square waves (there are bunch of soundwave generators available online) and notice how this effect is less pronounced now. This is because the saw and square waves have more harmonic content, I.e. more overtones meaning a lot of extra frequencies than just the fundamental note that you can make out and gives definition to the sound.
Since soundwaves occupy physical space and decrease in physical size as frequency increases there will be different frequencies cancelled out and amplified all the time but it has to be an exact duplicate and inversed to cancel out a sound.
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