Interpolation errors presented as a function of τ_scaled (bottom x-axis) and ρ_c (top x-axis) that resulted from the application of the full interpolation algorithm (cubic splines along tracks and linear across tracks) across the complete grid. Results are shown for all ν_1, 11 mode frequencies, when ρ_c is considered as the age proxy for interpolation. The transition mass, between radiative and convective cores in the MS, is 1.175 M_⊙ for this choice of f_ov. The bottom subplot zooms on the results for interpolation presented in the top subplot for δν_1, 11 between −1.2 and 1.4 μHz.