https://www.daniel-reed.co.uk/typefaces/dr-ivory/

Ivory started as an experiment by using musical intervals to determine the heights and widths of each letter. I did this by creating a grid that was split into intervals comprised of 2nds, 4ths, 5ths and 8ths. The idea came after reading a section of Robert Bringhurst’s Elements of Typographic Style where he used musical scales to make page widths and grids. Using these grid points created a condensed typeface with a unique style and irregular structure. The typeface was finished off by adding a subtle rounded edge with the same dimensions as a piano keys edge.