The concepts and design aspects of all-digital openloop audio power amplifiers, based on multilevel power converters, are presented. Innovative modulation techniques to reduce harmonic distortion of this type of amplifiers are also presented. A prototype of a digital multilevel audio power amplifier has been developed, implemented, and tested. THD plus noise performance comparisons between some class A, AB, and D amplifiers are presented. Results show that the proposed digital audio power amplifier can be a promising solution for a high-quality digital audio power amplifier.