Comparison of the rectified observed FEROS spectra (blue) with the synthetic spectra computed by our N-body model (orange). Residuals are also plotted (red). They are substantial for the Hδ line (see circles), where the continuum level is uncertain (between 405.1 and 412.6 nm). Nevertheless, most line features (including splits, blends, weak lines close to the continuum) are present in both observed and synthetic spectra, resulting in reliable RVs of individual stellar components (especially Ac1, Aa1; cf. Fig. 15).