The patent also describes adjusting the audio to single mode or multi-user mode. For example, when a single user is listening to music they would hear through a stereo sound mode. On the other hand, when two people are listening through both earphones, separate mono signals would be used. Apple's patent also details a way two users would be able to listen to completely different songs at the same time.
An electronic device may be coupled to an accessory such as a pair of earphones. The earphones may have multi-user sensor structures that determine whether or not the earphones are being shared by multiple users. The multi-user sensor structures may include an angle sensor configured to measure an angle at the Y-junction of a cable associated with the pair of headphones. When the first and second speakers are both located in the ears of a single user, the electronic device may perform functions such as playing audio content. When one of the speakers is located in an ear of a first user while the other of the speakers is located in an ear of a second user, the electronic device can automatically take actions such as switching from stereo to mono playback, playing a different type of audio content to each earphone, or other suitable action.
The patent discusses the use of a variety of different sensors to determine when multiple users were sharing the earphones. One 'angle sensor' would measure the angle at the Y-junction of the cables to determine how many people were using the earphones. The wider the angle, the more likely the earphones were being shared.
As always, Apple patents usually never see their way in actually products, but it is still very interesting to see the different research Apple is doing to improve the user experience.