Tone Colour

 Tone colour, also known as timbre, is a term that describes the quality of sound in music. Timbre is what makes a particular musical sound different from another, even when they have the same pitch and loudness. For instance, it is the difference between a guitar and a piano playing the same note at the same loudness. Both pieces have string instruments, (cellos, violins and a bass) but Gershwin's Overture has a full orchestra with wind and brass instruments, which gives it a different tone colour. There are more instruments in Gershwin's piece, while Piazzolla's is just a trio. Therefore, Gershwin's piece has a thicker and richer tone than Piazzolla's.