- Receiving Noise
- Transmitting Noise
Passive Noise Reduction: Good for Reducing all Noise Including Voices
Any stereo headset or headphone will provide some level of passive noise reduction, in fact any device that provides a physical barrier to your ear canal will reduce the audio level that you can hear.
Foam and leatherette ear cushions provide comfort plus create and acoustic seal to your ear. Earbuds sit inside your ear and provide greater isolation from external sounds
ACTIVE NOISE CANCELING (ANC): GOOD FOR REDUCING LOW FREQUENCY NOISE
Poly ANC technology uses microphones, one on the back of each speaker that respond well to bass frequencies. The microphones pick up the audio that the user would hear (noise + intended audio) this is fed into the ANC circuitry and inverted then played into the same audio path. This happens very quickly <500 milli seconds which is not perceptible. The result is the noise combined with the inverted noise cancel each other leaving just the intended audio.
Active noise canceling is very good at removing low frequency noise typically 80 to 700 Hz. Which is why you need both good passive headset design combined with ANC to achieve optimal noise canceling performance.
