Patent ID: 8755553

Claim:
An apparatus comprising: a transducer configured to generate sound; and a housing defining a first cavity and a second cavity, the first cavity and the second cavity being connected to the transducer; wherein the first cavity comprises a first sound outlet at a first surface of the housing; wherein the second cavity comprises a second sound outlet at the first surface of the housing and a third sound outlet at a second surface of the housing wherein at least one of the first and second cavities and/or at least one of the first and second sound outlets are configured to limit a sound pressure level of the generated sound at one or more frequencies and the third sound outlet is connecting at least one of the first and second cavities to the exterior of the apparatus, wherein at least one of the first and second cavities and at least one or more of the outlets is configured to limit the sound pressure level at one or more frequencies, wherein the third sound outlet is larger than the first and/or second sound outlets, wherein the third sound outlet is located on the housing and sized such that the third sound outlet is configured to be blocked, and wherein the first and second cavities and at least the second outlet is configured to limit the sound pressure level at the one or more frequencies while the third sound outlet is blocked.