Compensated velocity power spectra for decaying turbulence simulations at time t = 5 × 10^-3 using different timestep limits. The black solid line corresponds to the ideal 512³ run and the black dashed line to the ideal 1024³ run. The vertical dotted lines show the mean ambipolar diffusion scale, ⟨ k_AD ⟩, the numerical dissipation scales, k_m,512 and k_m,1024 of the two resolutions and the sonic scale, k_s (k_s and k_m,1024 are practically the same). Run B0, used as reference in the main body of the paper, uses a timestep limit dt = 0.05t_a, where t_a the Alfvén crossing time of a cell.