ER•4P (Portable)earphones can be used with
portable CD, MP3, DVD and other players without requiring
an additional amplifier. As compared to the ER•4S, the
ER•4P has 10 dB greater output at high frequencies and 13
dB greater output at low frequencies. The higher
sensitivity and enhanced bass of the ER•4P have made it the
most popular earphone for most uses.
ER•4S (Stereo)earphones were designed to compensate for
the high frequency emphasis in all CD recordings, in order
to provide accurate sound reproduction. Performing
musicians often use them as in-ear monitors because the
response of the ER•4S matches the response of most typical
monitor loudspeakers. The high accuracy and exceptional
sound isolation of the ER•4S have made these earphones
popular with musicians, recording engineers and
audiophiles. ER•4S earphones can be used with a headphone
amplifier when using low power portable devices.
ER•4B (Binaural)earphones are for the
binaural recording enthusiast. The ER•4B is an ideal
earphone for use with material that has not been equalized
for loudspeaker playback. It was developed from the ER-1
earphone that is referenced to a flat diffuse field and
used primarily for speech reception research, where the
goal is to produce the same frequency response at the
eardrum as would be produced in the live situation.