Alex is a multi-instrumentalist, composer and producer from Sydney, Australia. He founded the post-rock band sleepmakeswaves, with which he has toured Asia, America, Europe and Australia. In his spare time he writes music for short films, produces bands and subsists on altogether too much coffee. Alex is the instructor of the free Soundfly course, Live Clicks and Backing Tracks.
In 12-TET, you don’t define your intervals by tidy ratios of whole numbers. Instead, you divide up the octave into twelve equally-sized semitones (the interval between two adjacent piano keys or guitar frets). You then add semitones together to make all the other intervals. To go up a semitone from any note, you multiply its frequency by the 12th root of two. To go down a semitone from any note, you divide its frequency by the 12th root of two. If you go up by an octave (12 semitones), you’re multiplying your frequency by the 12th root of two 12 times, which works out to two.