Patent 8660289 was granted and assigned to Apple (company) on February, 2014 by the United States Patent and Trademark Office.
An earphone housing has a sound output port to be inserted into an ear. Multiple drivers are located in the housing. Each driver has a respective motor and a respective diaphragm. The diaphragm of one of the drivers is vented but that another is not. Other embodiments are also described and claimed.