Hi Hans-Christoph, > [vasp buf( -> [vasp.sqr] -> [vasp.?] -> [mean] -> [sqrt] -> RMS value oh yes, that's functional as well (although there's a huge list message produced by [vasp.?]....) As an aside, it would be interesting to create a spectrally weighted average (loudness)... vasp should provide all means to do that.... best greetings, Thomas