The ER-4P earphones were designed to match the response of the ear, creating nearly perfect sound reproduction. They reduce external sound naturally by sealing your ear canals, without the added weight, bulk, or external power supply required for active noise-canceling.

Their external noise exclusion (up to 33 dB using the supplied 3-flange eartips and 41 dB with foam eartips) lets you hear the full dynamic range of recordings without your having to play them at unnaturally high and unsafe levels.

Noise reduction with ER-4 MicroPro earphones occurs naturally from the inserts. Other earphones with active noise-cancelling add circuit noise and require bulky batteries.

The white 3-flange eartips provide 35 dB average external noise isolation. Foam eartips provide 41 dB average external noise isolation.

Lowering surrounding noise allows the listener to hear the full dynamic range of recordings at lower reproduction levels

* Noise isolation: 35-42 dB

* Maximum output: 122 dB SPL

* Weight: less than 1 oz.

* Response accuracy: 86%

* Frequency response: 50-10 kHz ± 2 dB; 20-16 kHz ±4 dB