There's a reason most cheap in-ear headphones sound the way they do – they only use one driver in each ear, which limits the audio range. To get more life, more spaciousness, and more oomph out of your favorite tracks, dual-driver earbuds are the answer and Apple has offered In-Ear headphones with dual-drives for some time. A dual-driver design is also especially good for listening to high-quality audio from lossless rips, to HD videos and other high-bitrate sources. In a new patent application published today by USPTO we see Apple describing possible changes to the internal audio design as well as talk about a three-way driver for the first time. According to Apple, their new invention relates to earphones or earbuds that have multiple speaker drivers and a cross-over network.