I recorded the same piece of music from different instruments and I want to compare their timbre by means of feature extraction. As you can see from the image, the recording is composed of different sections with very different amplitude values. Furthermore, the recordings present a slightly different RMS energy.
I am going to divide the recording into short frames and extract the features from each frame. I want the instruments to be comparable. For this reason I performed a RMS normalization on the whole recording before windowing and feature extraction, in such a way that each recording has a RMS value equal to 1. Am I right, or is there a better approach?