Question

What is the difference between an overtone and a harmonic?

Answer 1

Hint: Overtones and harmonics are generally studied in relationship to sound (Vibrations and Waves). These two terms are often confusing with each other. It is possible for harmonics to be overtones and for overtones to be harmonics. It is also possible to have those harmonics that are not overtones, and also those overtones which are not harmonics.

Complete step-by-step solution:
1. Overtone is a term implemented to any high order frequency standing wave, while the term harmonic is used for those cases in which the frequencies of the overtones are integral multiples of the fundamental frequency.
2. First Harmonic is the natural frequency of vibration while first overtone is the next higher frequency of vibration.
3. Harmonics are simply integral multiples of fundamental frequency while Overtone is not necessarily integral multiple of fundamental frequency.
4. All harmonic may or may not present in vibration while all overtones are always present in vibration.
5. Overtones include harmonics, but harmonics do not include overtones.
6. First overtone is not the fundamental but the second harmonic is the first overtone.
7. In stretched strings in first mode of vibration we get fundamental frequency of the vibration , in second mode of vibration we get first overtone and second harmonic while are \[{{n}^{th}}\]modes of vibration we get \[{{n}^{th}}\] harmonic and \[{{(n-1)}^{th}}\]overtone.
8. An overtone is then given to any resonant frequency above the fundamental frequency or fundamental tone while harmonic frequencies are whole number multiples of the fundamental frequency, or the lowest frequency of vibration.
9. The list of successive overtones for an object is called the overtone series while the list of successive harmonics is called harmonic series.
10. Overtones are any frequency at which resonance occurs above the fundamental frequency .These may happen at harmonics only or at specific harmonics only or at other values entirely.
11. In standing sound waves in an open pipe harmonics and overtones are the same. While in a closed organ pipe, overtones only occur at odd harmonics.

Note: When two sets of progressive waves of same type either longitudinal or transverse having same amplitude and same time period / frequency and travelling with same speed along same straight line in opposite directions superimpose then a new set of waves are formed .These new waves are called standing waves or stationary waves.