Best-fit modelling of the TNG/VHR-R spectrum of NGC 4156, as a representative example of our first fit with PPXF. Data are shown as solid black line along with the full best-fit model (red) and the separate models for each spectral component (different colours, see the legend). A first-degree polynomial or a broken power law (dashed black line) is used to reproduce the AGN contribution to the continuum emission.