a) Frequency residuals vs. frequency for two solar models in comparison with solar observations for a low-degree mode with l = 0. The differences are retrieved by . Shown are the 3D corrected model (black solid line), the standard 1D solar model (dashed lines) and a 1D model expanded with the turbulent elevation (dotted lines; see Eq. (7)). The height of zero differences is indicated (horizontal solid line). b) We also show the residuals for different modes scaled with Q_nl resulting from a solar model corrected with 3D model (GGM: gas gamma model) published by (Rosenthal et al. 1999; black symbols) in comparison with our result for l = 0 (red solid line).