Kinetic (solid lines) and magnetic (dashed lines) energy spectra as a function of the wave number k obtained in an horizontal slice of the convective box at y = 1.5. All spectra are averaged over the time interval 20 < t/τ_conv < 40 and are rescaled by b^2/3. The three panels show the results for different numbers of grid cells (from top to bottom: 64 × 32 × 64, 128 × 64 × 128, 192 × 96 × 192). The dotted black lines are the Kolmogorov (k^−5/3) and Kazantsev (k^3/2) scalings.