Based on the orthogonal fam functions a complex, orthogonal filterbank is produced to realize a running complex orthogonal auditory transform (COAT). COAT produces time- Bark distributions of the signals under analysis and gives analytic signal at the output of every critical band (Bark-channel). These signals can be further processed to make a detailed harmonic analysis. The harmonic structure can be utilized in its turn for estimation of the fundamental frequency (F0).