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Chapter 5: Notes on using the Speech Screen's Master Hearing Aid
Estimating the Required 2cc-Coupler SSPL 90
1. With the Hearing Aid Simulator set to “Off,” obtain an estimate of the patient’s Un-
comfortable Level (UCL) for speech.
2. Add 15 dB to the obtained speech UCL to estimate the required SSPL 90.
5.2 Complete Instructions for Using the Hearing Aid Simulator
There are many methods for fitting hearing aids. The choice of method is up to the individ-
ual professional. The instructions below are merely suggestions on how to use the Hearing
Aid Simulator; they are given as a guide to selecting gain, frequency response, and maximum
output. The suggested procedures can give the operator a starting point toward a final hear-
ing aid selection.
5.2.1 Selecting Gain and Frequency Response
Coarse MCL Estimate
The first step is to make a coarse estimate of the patient’s Most Comfortable Level (MCL) for
speech.
• Set the channel Input for “Mic” if you are going to use Live Voice, or select a recorded
speech channel as desired.
• Set the channel Output for “Phone.”
• Adjust the level control so that speech will be presented at 0 VU.
• Use the “Off” setting of the Hearing Aid Simulator.*
• While presenting speech materials or monitored live voice (as close as possible to
0 VU), raise and lower the “Hearing Level” dial until the patient indicates that the
speech is at a comfortable hearing level, not too loud, not too soft. There may be a
range of levels that satisfy this requirement. Choose the lowest level that is comfort-
able for the patient to listen to without straining.
Choosing a Slope and Final MCL
(Note: For “ski-slope” losses, use the separate procedure, below.)
Once you have established a “coarse MCL” setting, try changing the Hearing Aid Simulator
setting to other slopes, while asking the patient to judge the sound quality and intelligibility.
The goal here is to find the setting with the best balance between “clarity” and “pleasant-
ness.” If the patient indicates that one slope setting sounds louder or softer than another,
adjust the Hearing Level to achieve MCL at each setting you try.
*
When the audiogram slopes notably downward between 250 Hz and 1000 Hz, consider using the “6dB” setting. This
will cause the perceived loudness at “coarse MCL” to be closer to that obtained with the final slope setting. NOTE
WELL: The “MCL” obtained with anything but a flat slope (“Off” setting) is not standard, and therefore should not be
entered as “MCL” on an audiogram sheet without indicating the divergence from standard practice.
