We study a new method to evaluate the technical level of a musical performer, by considering only the evolutions of the spectral parameters during one tone. The proposed protocol may be considered as front end for music pedagogy related softwares that intend to provide feedback to the performer. Although this study only considers alto saxophone recordings, the evaluation protocol intends to be as generic as possible and may surely be considered for wider range of classical instruments from winds to bowed strings.

The image illustrates the kind of analysis that can be performed. Considering a "crescendo-descrescendo" note, one observe the evolution of the amplitude of the recorded sound. On top, very smooth evolution indicate a high level of control. At the bottom, typical defaults can be observed, like over blowing at the beginning and exhaustion at the end.