1. A system for synthesizing speech from text using a triphone unit selection database, the system comprising: a module configured to receive input text; a module configured to select a plurality of N phoneme units from the triphone unit selection database as candidate phonemes for synthesized speech based on the input text; a module configured to apply a cost process to select a set of phonemes from the candidate phonemes; and a module configured to synthesize speech using the selected set of phonemes.