Bose has introduced its new QuietComfort 15 Acoustic Noise Cancelling headphones, a replacement for the company’s aging QuietComfort 2 headphones. The QC 15s feature a newly-developed, more sophisticated approach to active noise reduction than their predecessors, placing microphones both inside and outside the earcup to better sense ambient sounds and produce an appropriate cancellation signal. Other features include new proprietary ear cushions for additional passive isolation, an around-the-ear design, the ability to run for roughly 35 hours on a single AAA battery, and the company’s TriPort acoustic headphone structure for stronger bass. The Bose QuietComfort 15 will be available in silver starting August 20th for $300.