Patent ID: 8379899

Claim:
An electro-acoustical transducer comprising a transducer housing, having one or more side walls and an inner space, the transducer comprising: a deflectable diaphragm responsive to received sound or adapted to generate sound, the diaphragm dividing the inner space of the housing into a first and a second, separate chambers; a sound port adapted to convey sound between the first chamber and the surroundings; and a channel extending between a first opening toward one of the first and second chambers and a second opening to the surroundings, the channel being adapted to facilitate gas flow there through between the first or second chamber and the surroundings, the channel having dimensions providing a transfer function between a sound pressure in the first or second chamber and a sound pressure at the second opening of the channel, the transfer function comprising a low pass filter having a cut-off frequency, measured under free field conditions, of less than 100 Hz, wherein at least a first part of the channel extends within one of the one or more side walls of the housing and along a plane of the one of the one or more side walls.