Acoustic Metamaterials constitute a new and promising generation of materials whose unconventional characteristics, based on "exotic" values of their acoustic index (from 0 to infinity, imaginary, even negative), open the way to many advanced applications such that wave-field spatial control (for high-resolution imaging and beamforming), ultra-absorption and cloaking (for insulation and stealth). Among all classes of metamaterials, the locally resonant metamaterials take advantage of low-frequency resonances of "small" inclusions. Thanks to those local resonators these metamaterials allow the full control of long-waves while keeping a small size (sometimes very small), giving rise to the name of "sub-wavelength" metamaterials. At that time, there is a great deal of interest for applications with those acoustic materials especially for insulation in the audible domain and for stealth in underwater acoustics. Also, but with probably a lower societal and strategic pressure, the issues for ultrasonic instrumentation and imaging are potentially significant. Nevertheless acoustic metamaterials are still mostly at the stage of conceptual objects of laboratory. The route of soft-matter techniques opens up many ways of designing and fabricating new materials thanks to their great variety of processes and to the physical/chemical properties of the involved constituents (polymers for instance). Turning to good account our recent successful developments of macro-porous resonators (polymeric foam micro-beads), which are a key-element for acoustic metamaterials, we are at the stage where we can envisage the making of many different types of metamaterial-based devices relying on a large range of index-values (now experimentally available). This proposal is a strongly multi-disciplinary project between three labs in Bordeaux, expert in wave-physics, soft-matter and microfluidics. The consortium has more than 5 years of experience in joint-research on the topic of soft-metamaterials. This long collaboration coupled to the geographical proximity and the developed complementary skills is a key-point for challenging both the material and the acoustic aspects of the project. The Material challenge is to develop a new class of acoustic coatings based on the metamaterials concept, which are easily processable and up-scalable. First the meta-matter can be a fluid-based dispersion like paint and turned afterwards into solid-but-soft coating upon polymerization over a large variety of surfaces. Second, the meta-coating can be structured by using soft-lithography and shaped by molding. In that project the possibilities for the resonators synthesis and their structuring into a metamaterial-device are quite vast. The Wave-Physics challenge concerns the design and the experimental proof of targeted functions of several demonstrators. The chosen functions, in connection with further breakthrough technologies, deals with first: sub-wavelength absorption in the context of insulation and stealth; and second: wave-field spatial control for beamforming/front-shaping and cloaking. The flow scheme of BRENNUS is the following: 1. Chemistry and synthesis of micro-resonators according to some criterions (size, shape, high calibration, surface treatment, mass production...) and formulation of the host matrix; 2. Structuring and shaping metamaterials using soft-matter techniques in order to achieve paint-like raw metamaterial, flexible coatings and molded structures; 3. Realization of three types of demonstrators: a. Sub-wavelength meta-coating for sound insulation and stealth b. Transducer caps for beamforming in ultrasonics c. Anisotropic meta-layers for cloaking structures