The track consists of essentially all the music that will accompany the vocal and typically includes drums and percussion, keyboards, and bass.
Live guitars or computer generated guitar sounds and additional instruments might also be included.
The only things missing are the topline – the vocal melody and the lyrics.
Source: How to Write to a Music Track: The Art of Toplining | MusicWorld | BMI.com
The post How to Write to a Music Track: The Art of Toplining first appeared on All About Songwriting.