Systems, apparatus, and methods for hearing protection

A method for protecting hearing of a listener in an environment, the method comprising:

• inserting at least a portion of a device in a human ear canal, the device having an outer shape defining a first opening for receiving incident acoustic energy from the environment and a second opening positioned opposite to the first opening for transmitting filtered acoustic energy into the ear canal, the device having a longitudinal axis extending from the first opening to the second opening;
• receiving incident acoustic energy from the environment via the first opening in the device, a first conduit extending inward from the first opening;
• selectively amplifying and/or dampening the acoustic energy via a cavity in fluid communication with the first conduit based on a resonance frequency of the cavity, the cavity further comprising a mesh element disposed in a plane substantially normal to the longitudinal axis, the mesh element dividing the cavity into a proximal compartment for receiving the acoustic energy from the first conduit and a distal compartment;
• selectively attenuating, based on a sound pressure level of acoustic energy in the cavity, acoustic energy from the cavity via liquid disposed in the distal compartment and a second conduit in fluid communication with the distal compartment and extending outward to the second opening, the liquid displaceable relative to the device in a direction substantially aligned with the longitudinal axis, the second conduit being tapered towards the second opening and receiving a portion of the displaced liquid in response to a sound pressure level of the acoustic energy, an extent of displacement of the liquid into the second conduit based on the sound pressure level of the acoustic energy, wherein no significant amount of the liquid is present in the proximal compartment, and wherein the second conduit selectively attenuates the acoustic energy based on the extend of displacement of the liquid into the second conduit;
• and
• transmitting the filtered acoustic energy via the second opening of the second conduit positioned opposite to the first opening along the longitudinal axis.

An apparatus for filtering acoustic energy in an environment, the apparatus comprising:

• a first conduit substantially aligned with a longitudinal axis, the first conduit defining a first opening for receiving incident acoustic energy from the environment;
• a cavity in fluid communication with the first conduit, the cavity for selectively amplifying and/or dampening the acoustic energy based on a resonance frequency of the cavity, the cavity comprising a moving element disposed in a distal compartment of the cavity and not being present in a proximal compartment of the cavity, the moving element displaceable relative to the apparatus in a direction substantially aligned with the longitudinal axis;
• and
• a second conduit substantially aligned with the longitudinal axis and in fluid communication with the cavity, the second conduit being tapered towards a second opening and for receiving a portion of the displaced moving element in response to a sound pressure level of the acoustic energy, an extent of displacement of the moving element into the second conduit based on the sound pressure level of the acoustic energy, the second conduit further for selectively attenuating acoustic energy from the cavity based on the extent of displacement of the moving element into the second conduit, the second opening positioned opposite to the first opening along the longitudinal axis for transmitting filtered acoustic energy.

A method for filtering acoustic energy in an environment, the method comprising:

• receiving incident acoustic energy from the environment via the first opening of a first conduit substantially aligned with a longitudinal axis;
• selectively amplifying and/or dampening the acoustic energy via a cavity in fluid communication with the first conduit based on a resonance frequency of the cavity, the cavity comprising a moving element disposed in a distal compartment of the cavity and not being present in a proximal compartment of the cavity, the moving element displaceable in a direction substantially aligned with the longitudinal axis;
• selectively attenuating acoustic energy from the cavity via a second conduit substantially aligned with the longitudinal axis and in fluid communication with the cavity, the second conduit being tapered towards a second opening and for receiving a portion of the displaced moving element in response to a sound pressure level of the acoustic energy, an extent of displacement of the moving element into the second conduit based on the sound pressure level of the acoustic energy, wherein the second conduit selectively attenuates the acoustic energy based on the extend of displacement of the liquid into the second conduit;
• and
• transmitting filtered acoustic energy via a second opening defined by the second conduit and positioned opposite to the first opening along the longitudinal axis.