The lowest frequency that can be produced is called the fundamental frequency and it has the greatest amplitude. I will therefore decide which note (f) you are listening to. The next higher frequency is twice (2X) the fundamental but has a smaller amplitude. The next higher frequency has thrice (3X) the fundamental but has a smaller amplitude, the list go on depending of the type of musical instrument. Sum up all these frequencies you get a unique sound of guitar that doesn't sound like a tuning fork. The fundamental frequency is only changed in its shape of waveform but not the frequency.
