The CN-H1 stellarator is a HELIAC, and re-build with partly renewed coils at the University of South China. We calculate a set of equilibria varying the helical current and compute their Alfvén and sound excitation spectrum. With a plot of the density of frequencies, we provide a proxy for the continuum damping and for the visibility of excitations in the diagnostics. Furthermore, we explore the importance of magnetic islands for the excitation spectrum of the device. Thereby we expand a numerical tool to include the modifications due to islands along with the so called slow-sound approximation. We find that the frequency of the geodesic acoustic mode vs. radius changes considerably even for a moderate island size which may have consequences for the zonal flow dynamics.