Professional jazz harmony is rarely played exactly as written on a lead sheet.
: Replacing a dominant 7th chord with another 7th chord a tritone away (e.g., Db7 instead of G7). It works because they share the same guide tones. 3. The Modal Pivot An Approach to Jazz Harmony
At its heart, jazz harmony evolved from the Western tonal system but added "extensions" to every chord. Professional jazz harmony is rarely played exactly as
: Instead of thinking "this is a C Major chord," think "this is a C Ionian sound." The scale and the chord become one entity. An Approach to Jazz Harmony
: In jazz, a "C major" triad is rarely enough. The basic unit is the 7th chord (maj7, m7, 7, m7b5).