earphones for apple iPod
Apple Wo rl dw i d e
Deve l o pers Co n fe re n ce
June 28-July 2, 2 0 0 4
I n - t h e - e a r
Earphones
• Noise isolating
• High accura cy
ER-4P (portable)
• Enhanced bass and higher sensitivity.
• For use with portable players.
The ER-4P has 10 dB greater
sensitivity at high frequencies and
13 dB more at low frequencies than
the ER-4S.
ER-4S (stereo)
• The same frequency response as the
ER-4P (except for the bass boost), but
less sensitive overall. To compensate
for reduced sensitivity, the ER-4S can
be used with a headphone amplifier
when using low-power portable
devices.
• Preferred by musicians.
ER-4B (binaural)
• For use with material that has not
been equalized for loudspeaker
playback.
• For the binaural recording enthusiast.
The Next Best Thing to Live Music
• For audiophiles, performing musicians and recording engineers
• Use for mixing, monitoring and critical listening
• Lightweight, compact, fits in your pocket; no battery required
Response Accuracy
ER-4 MicroPro earphones produce transparent, reference-quality sound. The lack of coloration results in smooth treble, full
bass and clear, natural reproduction of piano, percussion and orchestral music. ER-4 MicroPro earphones were designed to
match the acoustic response of the open ear.
Noise Isolation
ER-4 MicroPro earphones provide 35-40 dB of sound isolation. ER-4 MicroPro earphones reduce sound naturally, without the
internal noise of electronic noise cancellation.
ER-4 Measured Noise Isolation
ER-4 MicroPro
Earphones
(foam)
ER-4 MicroPro
Earphones
(3-flange)
EARCAL Laboratories, Indianapolis, IN
Response of ER-4 Earphones (referenced to open ear)
Frequency Response Note:
There are two different ways of
presenting frequency response data.
1. The responses shown at the left
have been normalized by the target
response of the open ear to live
performances (CD equalization).
2. The frequency responses shown
on the next page are measured on
the KEMAR manikin. These are
equivalent to probe-microphone
responses measured