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). 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. Deep house music rarely reaches a climax, but lingers on as a comfortable, relaxing sound. Though many of these traits have still carried through to modern Deep House, the genre has become much "techier" when compared to its roots.