Audioscan Verifit - Manual (Page 104)

Verifit ® User's Guide Version 3.12  May 2015
Fitting to targets for loud sounds
4. Select Test 2 & set stimulus to [MPO]. In test box mode, 90 dB tone bursts are presented at 1/3 octave
frequencies in a repeating sequence. In on-ear mode, a single sequence of 85 dB tone bursts is presented
when you press .
5. In test box mode, adjust high-level gain and/or output limiting (e.g.,MPO, PC) so the curve matches the +
REAR90 targets (DSL) or approaches but doesn’t exceed the RESR targets (NAL-NL1, NAL-NL2) at all
frequencies. Press to record the MPO curve. In on-ear mode, advise the client to point to the
screen if a sound becomes too loud during the test (see Max TM SPL setup). Press to run and
record a single sweep. Adjust the gain and output for loud sounds as for test box measures, factoring in client
response. Repeat as necessary.
Running a new test may automatically hide the speech envelope of the previous test, depending on the option
chosen in Setup (see Speechmap - Speechmap Setup). To redisplay, highlight and Hide/Show, then
highlight and the envelope display (right column) button for the test.
Fitting to targets for mid-level speech
6. Select Test 3 and set stimulus to [Speech-ISTS], [Speech-std(1)] or [Speech-std(2)] and level to 70.
Elongated + symbols show the target range for 70 dB speech LTASS.
7. Adjust gain for mid-level sounds so that the middle curve (the LTASS) falls within the target range. Press
to run the complete passage. Repeat as necessary. Achieving this goal may require adjusting
gain for soft speech, which will reduce its audibility. This may be a necessary compromise with some
hearing instruments and for clients with a very narrow dynamic range.
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