The same as in Figure 7 but for the velocity power spectra separated into compressible modes (velocity modes where ∣∇ × v∣ = 0) and solenoidal modes (velocity modes where ∣∇ · v∣ = 0). We show the compressible mode spectrum in the main panel, and the solenoidal modes are shown in the inset. The compressible mode spectrum shows a strong dichotomy between the strongly coupled (low-Pm_c) and weakly coupled (high-Pm_c) regimes, reducing power on all k when the CR fluid couples and becomes acoustically responsive. Unlike the compressible mode spectra, the solenoidal spectra remain invariant.