Active Noise Cancelling Headphone* This Active Noise Cancelling headphone sets the classroom standard when high stakes testing requires the quietest of individual settings. Califone understands the importance of blocking out external classroom noise has different implications than tuning out background sounds while on an airplane. This is why we've designed our NC500TFC to be used by itself to negate outside distractions, or when plugged into a computer or media player so students will be able to discern the subtle nuances in language learning for instance. The ability to block background noise when coupled with this innovative technology, provides the utmost in sound quality and speech clarity, and makes the NC500TFC ideal for use with computers, learning centers, and personal audio players. The secret behind the sound is a proprietary technology which alters the audio signal to make it easier to hear high frequency words or notes where clarity is often lost. The technology also increases the perception of loudness at the same time without actually increasing the volume. Previous technologies struggled to replicate the “live” experience because bass sounds masked the high tones. This made speech difficult to hear and made music sound muddled. The sound enhancement is made possible by creating high frequency harmonics that are not masked by low frequency sounds; filtering undesirable noise and reducing distortion. In the process it also provides for clearer sound and improved speech clarity even at lower volumes. This will encourage students to reduce the level of playback with the in-line volume control to a safe listening level to preserve hearing. The headphone is also the most comfortable in the award-winning line of classroom quality listening devices. Upgraded leatherette earpads and the lightweight ergonomic design help make the NC500TFC comfortable for extended periods of time.