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.
I love La Havas because she plays intricate yet simple guitar parts that have helped me become a better player. Her music spans genres and shows how diverse music is nowadays — she’s a gorgeous mixture of neo-soul, rock, jazz, pop, and soul, wrapped into one.