Audioscan Verifit 2 - Manual (Page 40)

Verifit ® User's Guide Version 4.2 © June 2015
Max TM SPL setup
The Max TM SPL safety feature allows you to set a limit on the SPL, measured by the probe microphone, above
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. Right-click the mouse to raise the home menu, then left-click , then left-click [Max TM SPL].
2. Click on the current Max TM SPL setting and select the desired Max TM SPL setting from the drop-down
list.
3. Click 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 Verifit 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.
ABR nHL to eHL setup
Estimated Hearing Level (eHL): An estimate of the behavioral pure tone threshold that accounts for a
measured ABR threshold.
Normalized Hearing Level (nHL): (a) Stimulus peak-to-peak equivalent SPL (pe SPL) at ABR threshold
relative to the average stimulus pe SPL at ABR threshold of a normal-hearing jury OR (b) stimulus SPL at ABR
threshold relative to the average stimulus SPL at behavioral threshold of a normal-hearing jury for the same
stimulus. (Note that in this latter case, nHL is equivalent to eHL).
In Speechmap/DSL you have the option of entering ABR thresholds in either eHL or nHL. If eHL is selected,
the threshold is treated as if it were a behavioral pure-tone threshold. If nHL is selected, the entered data will
first be converted to eHL before SPL threshold and fitting targets are calculated. To do this, appropriate eHL to
nHL conversion factors must be applied. You can choose to apply default conversion factors or enter new ones
for each client.
This setup allows you to select the default conversion factors that are applied in Speechmap/DSL to convert
ABR nHL threshold to eHL threshold.
1. Right-click the mouse to raise the home menu, then left-click , then left-click [ABR eHL to nHL].
2. Left-click [DSL defined] or [User defined]
3. For [User defined], enter conversion factors using a mouse or a keyboard. See Assessment data entry.
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.
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