ER•4 Background
Etymotic Was First
Etymotic Research
introduced the ER•4B and ER•4S earphones in 1991. The ER•4 series earphones are
in-the-ear, high-fidelity transducers developed specifically to combine flat
frequency response with isolation from external noise. The isolation of outside
sound makes it possible to listen at reduced levels, which prevents ear overload
distortion and hearing damage from excessive volume levels.
ER Is Still The Leader
Other in-ear earphone designs have tried to match the ER•4 MicroPro earphones,
but not one is comparable to the high fidelity, reference-quality sound or
the isolation of the ER•4. The word "Etymotic" means "true-to-the-ear," and
ER•4 MicroPro earphones produce the highest sound quality of any earphone
available.