MODEL- ER-4S               VENDOR- ETYMOTIC RESEARCH
    
FEATURES- ER 4P microPro Noise Isolating Earphones- White Box package
       Portable earphones can be used with portable CD, MP3, DVD and other 
        players without requiring an additional amplifier. The higher 
        sensitivity and enhanced bass of the ER-4P have made it the most 
        popular earphone for most uses. 
       The ER-4 MicroPro earphones are the next best thing to live music, 
        with noise isolation far surpassing that of active noise-canceling 
        earphones. The ER-4s require NO batteries, and can be plugged into 
        any audio source. Their external noise exclusion -- 35 dB with
        3-flange eartips, 42 dB with foam eartips -- allows you to hear the 
        full dynamic range of recordings without having to play them at 
        unnaturally high and unsafe levels.
         - Transparent, reference-quality sound
         - For audiophiles, performing musicians and recording engineers
         - For mixing, monitoring and critical listening
         - Accurate real-ear response
         - Unsurpassed isolation from outside sound 
    Includes ER-4 MicroPro earphones, 5 ft. cord with 3.5 mm stereo phone 
      plug, 1/4" stereo phone adapter plug, Six 3-flange eartips, 10 foam 
      eartips, Filter changing tool, 4 replacement filters, Shirt clip,
      Pouch and Storage box.
* Response Accuracy 
   ER-4 MicroPro Earphones are designed to match the acoustic response of 
   the open ear. Music is naturally bright, but not harsh. The lack of 
   coloration results in smooth treble, full bass, clear and natural piano, 
   percussion and orchestral music. 
* Noise Reduction 
   ER-4 MicroPro Earphones provide the highest isolation of any earphone: 
   35~42 dB (two to three times that of active noise-canceling earphones). 
   ER~4 MicroPro earphones reduce sound naturally, without the added 
   weight, bulk, or external power supply required for active noise-
   canceling. 
    - 3-flange eartips: 35 dB external noise isolation (NRR = 22dB)
    - Black foam eartips: 42 dB external noise isolation (NRR = 32dB) 
     
  -- SPECIFICATIONs ----------------------------------
FREQUENCY RESPONSE- 20 Hz to 16 kHz +/- 4 dB
TRANSDUCER TYPE   - dynamic
1 kHz SENSITIVITY - 108 dB SPL for a .25v input
IMPEDANCE         - 27 Ohms nominal
MAXIMUM OUTPUT    - 122 dB SPL
CONTINUOUS INPUT  - Maximum .75 Vrms
WEIGHT            - less than 1 oz. 
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