This is a spectrogram of the open E string on a Fender Stratocaster. The white lines of energy, are the many frequencies that combine in varying amplitudes to create the E note. I have been extracting these frequencies manually from Izotope RX and then converting them to sinusoids.
I am interested in the internal tonality of a single note, taking inspiration from Gérard Grisey's classic spectral piece 'Partials' (1975) which is based on the specrogram of E2 on a Trombone.
Using spectral frequency information, means that you can explore the internal relationships of a sound;