Top: characteristic time τ_eff as a function of ν_max. The dots have the same meaning as in Fig. 1. The green curve correspond to a linear scaling in while the red curve is a power law of the form with the slope p =  −0.94 obtained by fitting the power law to the theoretical values of τ_eff (filled red squares). The filled green square corresponds to the value τ_eff = 173 s found for the solar 3D model (the last model in Table 1). Bottom: τ_eff as a function of the scaling z₂ = (ν_max/ν_ref)   (ℳ_a/ℳ_a,0) where ℳ_a is supposed to scale according to Eq. (17). The symbols have the same meaning as in Fig. 1. The green line corresponds to a linear scaling in z₂, while the red curve to a power law of the form where the slope p = 0.98 is obtained by fitting the theoretical values of τ_eff (red squares). The horizontal error bars show the uncertainty in z₂ associated with a typical uncertainty of 100 K (rms) in T_eff. The blue horizontal error bar corresponds to a typical MS and the black one to a typical RG star.