Audioscan Axiom - Manual (Page 59)

Axiom ® User's Guide Version 1.8  May 2015
which a test terminates. The MAX TM SPL limit is shown on all on-ear measurement screens. The default limit
is 120 dB.
To choose a different Max TM SPL setting:
1. Click on then click on [Max TM SPL] in the Setup menu.
2. Click on the Max TM SPL pull-down menu.
3. Click on the desired Max TM SPL setting from the drop-down list.
4. Click on to exit Setup.
This Max TM SPL setting will be in effect until you change it.
If the limit is exceeded during an on-ear test, the Axiom will terminate the test and display the message 'MAX
TM SPL EXCEEDED'. You must then decide to either reduce the maximum output limit of the hearing
instrument or increase the Max TM SPL setting following the steps above.
If the MAX TM SPL limit has been disabled, a notice will appear on each real-ear screen. Also, a message
reminding you that the MAX TM SPL limit has been disabled will appear when you select an on-ear test.
Positioning the client
Sound reflections from nearby surfaces (including the operator) can cause large measurement errors, especially
if the client moves between REUR and REAR measurements. Room noise can increase test time, cause errors
and alter the operation of the hearing instrument being evaluated.
1. Choose a quiet location and position the client and the sound-field speaker at least 1.5 m (5 feet) away from
any hard surfaces.
2. Position the client directly in front of, and facing, the sound-field speaker at a distance of 45 to 90 cm (18 to
36 in.) from the center of the head.
Positioning the probe tube
1. Use an otoscope to ensure there is no ear canal obstruction (e.g. cerumen) and to get a sense of ear canal
length.
2. Install a new probe tube on the probe module. Set the black marker ring approximately 28 mm from end of
probe tube for adult females, approximately 30 mm from end of probe tube for adult males and
approximately 20-25 mm from end of probe tube for children. These positions may be modified based on the
otoscopic examination. (Tip - the probe module body is 28 mm long.)
3. Hang the probe module on the ear, as shown. The reference microphone should face outwards.
4. Adjust the blue cord until the probe module is snug against the head, directly below the earlobe (cheek
level). To facilitate this, clip the probe module cable to clothing on the side opposite the test ear and draw
the cable snug.
5. Hold the front blue cord so that it passes behind the ear canal entrance and pass the end of the probe tube in
front of the blue cord and into the ear canal.
6. Carefully slide the probe tube into the ear canal until the marker ring approaches the intertragal notch. Then
let the front blue cord move forward to hold the probe tube in place. Use an otoscope to verify that the tube
is 2 to 5 mm from the eardrum.
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