We show how resonant (near-field) coupling affects wave transport in disordered media through ultrasonic experiments in concentrated suspensions. The samples consist of resonant emulsions in which oil droplets are suspended in a liquid gel. By varying the volume fraction of droplets $\varphi$ up to 40%, the limits of the independent scattering approximation are experimentally demonstrated as soon as $\varphi >10\%$. For these concentrated samples, the proximity of resonant scatterers induces a renormalization of the surrounding medium, leading to a reduction in scattering strength. Hence, maximum scattering is reached at an intermediate droplet concentration $(20\%<\varphi <30\%)$ where subdiffusive wave transport is observed. These results are very relevant for designing materials for the study of wave transport phenomena such as Anderson localization.

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• Acoustic measurements
• Ballistic transport
• Diffusion
• Transport phenomena
• Emulsions
• Random & disordered media
• Ultrasound techniques