1. A concatenation cost database stored in a computer-readable medium, the concatenation cost database generated according to a method comprising: synthesizing a body of speech; identifying acoustic unit sequential pairs generated in the body of speech and their respective concatenation costs; and storing the respective concatenation costs in a concatenation cost database.
5. The concatenation cost database of claim 1 , wherein the identified acoustic unit sequential pairs are a subset of all acoustic unit sequential pairs generated from the synthesized speech.