Apple Patent: Headphones That Also Function as Speakers

Apple has filed a patent application for “dual mode headphones,” Patently Apple reported Thursday. The patent application describes headphones that can operate both at low volume levels for traditional listening and at high volume levels when removed from a user’s ears, replicating the experience of a desktop speaker.

The patent application, first filed in May 2, 2011 by then Apple employee Edward C. Hyatt, describes how such a headphone design could be convenient for users:

Portable electronic devices have become common place in our society. Users typically listen to content on their portable devices using headphones, although there are speakers available that can be connected to the portable devices to enable multiple users to listen in at the same time. This approach, however, may require a user to carry both a headphone and speakers, or may require the user to rely on speakers built into the device, which may not be as powerful or have as high a sound quality as external speakers.

This inconvenience can be solved by including an amplifier in the headphones that is only used to boost the audio volume when the headphones are configured for “speaker mode:”

Because the headphones may need to provide a louder output in a speaker mode, the headphones can include an amplifier that may be used to amplify audio signals in the speaker mode. The amplifier can be bypassed or turned off in an in-ear mode. The user can enable the speaker mode, and thus make use of the amplifier, using different approaches. For example, a user can press an appropriate button. As another example, the headphones can detect that the body has been positioned in the speaker position, and automatically change to the speaker mode.

To ensure that a user does not damage their hearing by inadvertently using the headphones with the amplifier turned on, the patent suggests that a variety of sensors, including proximity and impedance sensors, be used to determine when the headphones are configured for speaker mode and when they are on a user’s ears.

Beyond the technical descriptions of how the headphones would operate, Apple describes a number of different designs for its proposed dual mode headphones, including both in-ear and over-the-ear configurations.

As with all Apple patent applications, it is unclear if Apple is actively pursuing this dual mode headphone design. It is also not known if this design, when reduced to practical implementation, is useful. With speaker drivers small enough to fit comfortably in headphones, particularly in-ear headphones, it is difficult to imagine any amount of engineering and amplification that could combine to provide adequate sound quality.

Teaser graphic via Shutterstock.