ok so i have a major confusion and its really getting to me. So from what i understand of harmonics, the length of the medium is always fixed and only the frequency changes. Is this right? Then why, on organ pipes for example.Assume open open configuration. Say I play a middle tone note C, wouldnt the fundamental frequency length be half the length of the wave. The 2nd harmonic would be 2 times that and the third harmonic would be 3 times the fundamental frequency wave length and so on? so why is it changing? shouldn't the length be the same and only the frequency change? im so confused pls help!