This book reflects the state of the art in important areas of speech and audio signal processing. sufficient amount of space covered by a multi-microphone systems, specific approaches to reduce noise, and evaluation of the voice signal and speech processing systems. Multi-microphone systems include automatic calibration microphone, sound source localization and source separation procedure. In addition, a method for reducing engine noise and proposals to improve the signal / noise ratio based on partial signal reconstruction or using a noise reference are reported. Procedures to reduce audio echo signal can help to improve the clarity of speech and speech recognition rate. In addition, solutions for special applications in speech and audio signal processing are reported including, for example, increasing the audio signal reproduction in automobiles and automatic evaluation of hands-free systems and hearing aids.