| 摘要 |
Disclosed are passive acoustic structures, portable audio devices configured for use with the passive acoustic structures and methods for enhancing the frequency output of a speaker of a portable device configured for use with a disclosed passive acoustic structure. The disclosed portable audio device may include an opening proximal a speaker cavity of the device, a shutter or door to open and close the opening so that the device interoperates with a docking station of a passive acoustic structure including a labyrinth or a transmission line system that may increase the frequency range of the system. For an end user to experience the music and multimedia features of a portable audio device, and in particular a mobile communication device, the above-described passive acoustic structure may provide a bass enhancement for the typically small loudspeaker of a portable audio device with no additional loudspeaker and therefore no additional circuitry. |
