We know music is pleasurable, the question is why?
This article did not mention overtones:<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Overtone" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Overtone</a><p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Harmonic_series_(music)" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Harmonic_series_(music)</a><p>Combinations of frequencies that form simple integer ratios are naturally perceived as being consonant, no culture or upbringing needed. As the ratios begin to involve higher integers and become more complex, the intervals they produce are considered more dissonant.<p>For instance, in ancient Greece, the scales were constructed by combining intervals where the integer ratios have a prime number no higher than 3. The result is a very consonant but almost bland music. Something you could easily fall asleep to.<p>The major and minor scales from which classical music is composed are made by combining intervals with a prime no higher than 5. This adds more dissonance and makes things a bit more interesting.<p>Scales based around higher prime numbers (7,11,13,..) are outside the scope of mainstream music although jazz is said to approximate the scales that could be built off the &#x27;7-limit&#x27; intervals, which explains its more dissonant nature (heavy use of tritone which has a ratio of 7:5, and the &#x27;minor seventh&#x27; approximates the interval with a ratio of 7:4).<p>That covers consonance, but it doesn&#x27;t explain emotional affect. I think one example that is at least a part of the explanation can be seen in the distinction between the overtones and undertones.<p>The major scale (and more specifically the major chord) of today&#x27;s western music is generally considered to be happy, confident, uplifted, etc. The major chord appears naturally in the harmonic series of overtones (any 3 notes played together whose frequency ratio is 4:5:6).<p>The minor chord, on the other hand, appears naturally in the undertone series which is just an inversion of the overtones (1&#x2F;4:1&#x2F;5:1&#x2F;6). It also occurs in nature like the overtones, although less frequently.<p>I may have flubbed some details as I&#x27;m writing off the top of my head mostly but I think it covers the gist of how harmony can contribute to the perception of music. There is of course also the rhythm and the sense of expectations&#x2F;irony involved in writing as well.