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TABLE OF CONTENTS
About Etymotic Research, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
About ER-4 Earphones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
System Includes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Eartips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Insertion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Changing Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Proper Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Noise Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Response Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
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ABOUT ETYMOTIC RESEARCH, INC.
Etymotic Research,Inc.(ER) is a research,development and manufacturing
company that designs products to measure,improve and protect hearing.
ER has developed some of the most innovative hearing technology available
today. Etymotic means “true to the ear.”
Other ETYMOTIC RESEARCH products:
ER-6 Isolator
™
insert earphones
Musicians Earplugs (custom hearing protection)
ER-20 High Fidelity earplugs
ETY-COM
™
cellphone headset
2
WARRANTY
Etymotic Research,Inc.warrants this product against defects in material
or workmanship for a period of 1 year from the date of original purchase
from an authorized Etymotic distributor or reseller. Proof of purchase is
required. The warranty can be extended for 1 additional year if Etymotic
receives a warranty card with proof of purchase any time within the first
year. ER will repair or replace the defective product at its option if returned
within the warranty period to our service facility. This warranty is in lieu
of all other warranties, expressed or implied, including,but not limited to,
any implied warranty of merchantability or fitness for a particular purpose.
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ABOUT ETYMOTIC RESEARCH
3
ABOUT ER-4 EARPHONES
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.
In-the-ear, high fidelity transducers combine flat frequency response
with isolation from external noise.
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.
ER-4 MicroPro earphones are ideal for a variety of consumer uses
such as personal CD and DVD players,MP3 players,and computers.
Professional uses include mixing and stage monitoring in the studio
and during live performance.
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ABOUT ETYMOTIC RESEARCH
4
DESCRIPTIONS
ER-4P (Portable) earphones have enhanced bass and higher sensitivity.
ER-4Ps can be used with portable CD,MP3,DVD and other players without
requiring an additional amplifier. The ER-4P has 10 dB greater sensitivity
at high frequencies and 13 dB more at low frequencies than the ER-4S.
The higher sensitivity and enhanced bass of the ER-4P have made it the
most popular earphone for most uses.
ER-4S (Stereo) earphones have the most accurate frequency response for
reproducing CD and MP3 recordings. The sensitivity is comparable to home
and professional earphones. ER-4S earphones are ideal for home stereo use
and computer use. ER-4S earphones can be used with a headphone amplifier
when using low power portable devices. ER-4S is the earphone preferred
by musicians and audiophiles.
ER-4B (Binaural) earphones are for the binaural recording enthusiast.
The ER-4B is the reference earphone for use with material that has not been
equalized for loudspeaker playback.
ER-4B
ER-4S ER-4P
•••
Lightweight and portable
•••
High accuracy
•••
Noise isolation (20-25 dB)
•
Enhanced bass response