Question

Find the frequency of the 6th note of a Major scale starting with a root frequency of 100.0Hz, assuming an equal temperament scale.

Answer 1

The basis of audio fractional octave bands is a frequency of 1000Hz. There are two ISO and ANSI approved ways in which the exact centre frequencies may be defined. One scheme is the base2 method where the ratio between 2 exact centre frequencies is given by 2^(1/N) with N as 3 for 1/3 octaves and so on. The other method is the base 10 method where the ratio is given by 10^(3/[10N]). This ratio may also be written as 2^(3/[10Nlog2]).

upper = centre * 2^1/6

=112.5Hz