>>11665616As people have said before, soundwaves are never perfect sound waves. And if you learned about fourier series, you should know that any periodic function can be represented as a series of sines/cosines. For instance, if you have a perfect square wave, there are an infinite amount of harmonics in it (although you cannot hear all of them due to the human ear having a limited range of frequencies it can hear). Although the square wave has a specific frequency, it definitely does not sound the same as a sine wave with the same frequency. Here is a video that shows the difference between different wave form sounds:
https://www.youtube.com/watch?v=v4XG_NHLWcs 
