Installation & Operation Manual

Wilat_Op_Man_23Oct08.doc CONFIDENTIAL
Aearo Technologies Page 4 of 21 18/07/2007
1. Introduction
Congratulations on the purchase of your new E-A-R-TONE
®
WiLAT Audiometric Earphone
System. The E-A-RTONE

WiLAT has been designed to replace the wired connection between
an audiometer and its earphones, bone conduction oscillator, and patient response button with a
wireless link. Test subjects within, or as required outside of a sound isolated room, can receive
calibrated air and bone conduction signals from an audiometer without the inconvenience and
frailty of a wired tether between the transducers and the audiometer or the sound room inside
wall. With appropriate set up and calibration, the E-A-R-TONE
®
WiLAT system will maintain the
(ANSI/IEC) specified characteristics for audiometers that require10Ω or 50Ω transducers, without
a wire connection between the test subject and the audiometer. The E-A-R-TONE
®
WiLAT
utilizes a redesigned E-A-RTONE 5A Insert Earphone as its transducer, providing all of the
clinical advantages of audiometric insert earphones in addition to remote operation capability.
Because the subject’s external canal is sealed with an E-A-R-LINK
®
foam plug, which functions
both as a sound delivery system and ambient noise attenuator, reliable threshold measurement
can be accomplished in environments unsuitable for hearing testing with a traditional supra-aural
earphone.
Direct coupling also produces greater sound separation between ears across the test frequency
range. Clinically, that means more instances where the need for masking is eliminated, or the
level necessary for effective masking is lower. Your average testing time will decrease without
sacrificing reliability. The higher inter-aural attenuation values, relative to the accepted supra-
aural values, cited in the Table 3.2 on page 13 of this manual should be applied. Basic masking
procedures are otherwise unaffected, i.e. only the crossover values in dB HL need to be adjusted.
E-A-R-LINK
®
tips are available in five sizes; three foam, and two PVC versions for infant testing.
The standard (3A) size foam eartip will comfortably fit most adult ear canals, a smaller (3B) size
is appropriate for pediatric testing, and an extra large (3C) size can be used to couple the
transducers to very large or surgically altered ear canals. To accommodate EACs too small for
the 3B tip, 3.5mm and 4.0mm PVC “Infant Eartips” are now available for your youngest patients.
E-A-RLINK tips should be disposed of after each use. Disposable plugs insure that sanitary
conditions exist for every test you perform, and the task of cleaning a headband and earphone
cushions is eliminated.
The WiLAT System can be set for either 10Ω or 50Ω impedance to match the output of most
commercially available audiometers. The E-A-RTONE
®
WiLAT is not compatible with audiometric
equipment designed for transducers with input impedance in excess of 50 ohms.
The RETSPL values and procedure for insert earphones cited in the ANSI S3.6–2004 Standard,
and reproduced in this booklet, must be used to calibrate your audiometer, before initial use, and
at least annually thereafter.
This instruction booklet is intended to provide information to allow you to perform hearing testing
with your audiometer and the E-A-RTONE
®
WiLAT System with the confidence that test results
will be comparable to, or in certain instances more reliable than, measurements performed with
supra-aural earphones. Most questions regarding the use and calibration of the WiLAT can be
answered by reviewing this booklet and/or ANSI S3.6-2004, or its subsequent revision(s). For
information regarding technical assistance or replacement items, please contact your distributor,
or E-A-R Auditory Systems Customer Service at: [e-mail]
.