Power spectrum of the self-generated B, calculated in a region of 5000 c/ω_p upstream of the shock (M = 10, run E), for three different obliquities as in the legend. The dashed line corresponds to wavenumber k ≈ 1/r_L(E_sh), and symbols correspond to F(k)∝k⁻¹. Configurations at = 0° and 45° are quite similar to each other and agree nicely with DSA prediction, while the magnetic energy for the quasi-perpendicular shock is significantly smaller.