Passive noise cancellation (PNC) is a traditional method of reducing unwanted noise without the use of microphones or amplifiers. It relies on physical barriers, such as closed-back ear cups or snug in-ear buds, to block out external sounds. This approach is also known as passive noise isolation or reduction. While it doesn't actively block out noise, it can help reduce the amount of environmental noise that is heard, making it a more affordable option compared to active noise cancellation (ANC) technology
. Passive noise cancellation is achieved through the use of well-designed ear cups and earbud seals, creating a physical barrier between the ears and external sounds. On the other hand, active noise cancellation involves the use of microphones to pick up external noise and generate phase-inverted sound to cancel it out. While active noise cancellation can provide a more comprehensive reduction of ambient noise, passive noise cancellation can still be effective in reducing the amount of noise that is heard, especially in environments with consistent background noise
. In summary, passive noise cancellation is a traditional, non-electronic method of reducing unwanted noise, relying on physical barriers to block out external sounds, while active noise cancellation uses microphones and electronic processing to neutralize ambient noise. The choice between the two depends on individual preferences and the specific noise-cancelling needs
