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We deal with the point-interaction approximations for the acoustic wavefields generated by a cluster of highly contrasted bubbles for a wide range ofdensities and bulk moduli contrasts. We derive the equivalent fields when thecluster of bubbles is appropriately distributed (but not necessarilyperiodically) in a bounded domain $\Omega$ of $\mathbb{R}^3$. We handle twosituations.  1. In the first one, we distribute the bubbles to occupy a $3$ dimensionaldomain. For this case, we show that the equivalent speed of propagation changessign when the medium is excited with frequencies smaller or larger than (butnot necessarily close to) the Minnaert resonance. As a consequence, this mediumbehaves as a reflective or absorbing depending on whether the used frequency issmaller or larger than this resonance. In addition, if the used frequency isextremely close to this resonance, for a cluster of bubbles with density abovea certain threshold, then the medium behaves as a 'wall', i.e. allowing noincident sound to penetrate.  2. In the second one, we distribute the bubbles to occupy a $2$ dimensional(open or closed) surface, not necessarily flat. For this case, we show that theequivalent medium is modeled by a Dirac potential supported on that surface.The sign of the surface potential changes for frequencies smaller or largerthan the Minnaert resonance, i.e. it behaves as a smart metasurface reducing oramplifying the transmitted sound across it. As in the $3$D case, if the usedfrequency is extremely close to this resonance, for a cluster of bubbles withdensity above an appropriate threshold, then the surface allows no incidentsound to be transmitted across the surface, i.e. it behaves as a white screen.

The equivalent media generated by bubbles of high contrasts: Volumetric metamaterials and metasurfaces