| CPC F24F 13/24 (2013.01) [B32B 3/266 (2013.01); B32B 3/30 (2013.01); B32B 15/08 (2013.01); B32B 2307/102 (2013.01); B32B 2307/732 (2013.01)] | 20 Claims |

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1. A low noise climate control device comprising:
a housing;
a noise producing component within the housing; and
an acoustic metamaterial stack arranged in the housing, the acoustic metamaterial stack including:
a first perforated layer arranged over a spacer layer, the spacer layer arranged over a second perforated layer, and
the first and second perforated layers each including a plurality of perforations creating a percentage of open area (POA) in each of the first and second perforated layers,
wherein the first and second perforated layers each further include two or more sheets, each sheet including a plurality of openings,
wherein the two or more sheets for each perforated layer are arranged such that the plurality of openings in the two or more sheets for each perforated layer coordinate to create the plurality of perforations in each of the perforated layers.
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