Deep house is known for complex melody, use of unrelated chromatic chords underlying most sequences, and a soul, ambient, or lounge vibe to the vocals (if any). It is a style of house music that blends elements of Chicago house, 80s soul, jazz-funk and Detroit techno. Deep house commonly appeared as a genre in the early 90s with more melodic sounds gathering influences from soul, jazz and African beats. In the early compositions (1988–89), influences of jazz music were most frequently brought out by using more complex chords than simple triads (7ths, 9ths, 13ths, suspensions, alterations) which are held for many bars and give compositions a slightly dissonant feel. The use of vocals became more common in deep house than in many other forms of house music. Sonic qualities include soulful vocals (if vocals are included), slow and concentrated dissonant melodies, and a smooth, stylish, and chic demeanor.

Stephen L Thorne1972