Hearing a simple scale does not usually evoke unusual sensations. Even nonmusicians can wander over to a piano and play adjacent keys - creating sounds that seem utterly routine because they are the basic building blocks of Western music. This traditional system is based on an interval, the octave, in which the high note is double the frequency of the low note. To get the rest of the notes, the octave is divided into 12 equal steps, creating the basic framework for everything from a sonata to a ringtone.
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Symphony in J flat - The Boston Globe
Just when you thought you had music theory sussed, they go and change the rules! Don't worry, we don't think the ABRSM will be testing you on the scale of J flat any time soon :o)