Tritone Substitution

TBD

• Tritone substitution moves the dom7 by a tritone. This moves the root by a tritone but keeps the 3rd and the 7th the same!
  
  

• It also moves the root of the dom7 to a step above the root. If you play a 2-5-1 here, you walk down in half steps do the root for some nice chromaticism.

• Can  play alt scale over the tritone sub. For example,  if you sub in Db7 for G7, you could play G7alt. This is because Db7 is made up of Db (#11), F (b7), Ab (b9), and B (3).
  
  In a minor 2-5-1 you can sub the min7b5 on the 2. effectively produces a chromatic step down to the 5, really cool.