Transcript Real-ear Measurements with the A-35

Real-ear Measurements
with the A-35
Presented by: Kristina Frye
Frye Electronics, Inc
Topics
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Interface from the A-35
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Entering an Audiogram and Creating a Target
Performing Insertion Gain Measurements
Measurements in SPL: Comparing HTLs and
UCLs
Testing with Visible Speech
Testing Open Fit Hearing Aids
Doing all this from the FONIX NOAH
Module
FP35 Real-ear Screens
Audiogram Entry
 Real-ear SPL
 Unaided & Aided
 Insertion Gain
Move between these four screens by using
NEXT and BACK
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Audiogram Entry Screen
Amplitude
Frequency
F2 — Select
HTL/UCL/Bone
F3 — Generate Target
NAL-NL1 Target Settings
Press MENU and BACK to change target
settings
 Compression
 Channels (1-18)
 Aid Limiting (Type of output limiting)
 Fit Type (Unilateral or Bilateral)
 Reference (Almost always Head Surface)
The Compression and Channels settings
have the most impact on the target!
Insertion Gain Testing
Press NEXT until you enter the Real-ear
Insertion Gain screen
Traditional Real-ear Protocol
Measuring the Insertion Gain
Response
Let’s get sidetracked for a few
minutes…
PROS and CONS of Measuring
the Unaided Response
Save Time!
To save testing time, you can probably skip
the unaided response measurement!
Thresholds are measured with an occluded
response
 Targets are generated from those
thresholds
 Many hearing aids alter the ear canal
resonance when inserted, so the unaided
response is extraneous data
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Exceptions
When is the unaided response useful?
Fitting a mild/moderate loss: Make sure
that the hearing aid is proving a benefit to
the patient
 Checking the position of the probe
microphone
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Back to the Protocol…
Proper Placement of Microphones
Above the Pinna
Ref
Mic
Marked 30 mm
from the tip for Adults
and 25 mm for children
Inter-Tragal
Notch
Probe Mic
Level the Sound Field Speaker
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Internal sound chamber
converts to sound field
speaker; should be ear
height
12 inches from the speaker
at 45° angle
Stand away from the
patient/loudspeaker during
measurements
The hearing aid (if silent)
and/or probe tube can be
inserted during leveling
Press F5 and START in the Real-ear
Measurement screen to level the sound
field speaker
Choose the Curve with F2
Four Curves Available
 Unaided
 Ins. Gain #1: 50 dB
 Ins. Gain #2: 70 dB
 Ins. Gain #3: 90 dB
Selected curve shown above F2
Testing Protocol
For Quick Testing, measure only Ins. Gain
#2. This measures at average speech level
(70 dB SPL)
 For Complete Testing, measure Ins. Gain
#1, #2, and #3 (50, 70, and 90 dB SPL)
 If no unaided response is measured, the
average is automatically substituted
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Example of Insertion Gain Meas
Prescription: This patient could use more amplification between
2000-6000 Hz!
Overview for Quick Insertion Gain
Testing
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Enter Audiogram Entry screen
Press F2 from Opening Screen. Use NEXT and BACK if necessary
Input audiogram and generate target
Use arrow keys to enter audiogram. Press F3 to generate target.
Enter Insertion Gain screen
Use NEXT until screen appears
Level the sound field speaker
Press F5 and START
Measure Ins. Gain #2 and fit to target
Use F2 to select curve. Press START/STOP to start and stop test
If desired, also measure Unaided response and
Aided Curve #1 and #3
The Real-ear SPL Protocol
Compare the Real-ear Response
to HTLs and UCLs on one graph
Real-ear SPL Screen
UCLs
Target
HTLs
Real-ear SPL Measurements
Goal:
Aided 3 below UCLs
Aided 2 meet target
Aided 1 above HTLs
Overview of the SPL Protocol
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Enter Audiogram Entry screen
Press F2 from Opening Screen. Use NEXT and BACK if necessary
Input audiogram and generate target
Use arrow keys to enter audiogram. Press F3 to generate target.
Enter Real-ear SPL screen
Use NEXT until screen appears
Level the sound field speaker
Press F5 and START
Measure Aided #1 to compare to HTLs
Use F2 to select curve. Press START/STOP to start and stop test
Measure Aided #2 to compare to the target
Measure Aided #3 to compare to UCLs
Visible Speech
Use External Signals such as Live Voice in
the real-ear measurements
 Perform this measurement in the Real-ear
SPL screen
 NEW! Both the real-time response and the
average response are displayed
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Example of Visible Speech
Average
Response
Real-time
Response
Visible Speech Protocol
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Enter Audiogram Entry screen
Press F2 from Opening Screen. Use NEXT and BACK if necessary
Input audiogram and generate target
Use arrow keys to enter audiogram. Press F3 to generate target.
Enter Real-ear SPL screen
Use NEXT until screen appears
Put analyzer in Spectrum Analysis mode
Use F4 to select the source type. Use DOWN arrow to turn source OFF.
Perform Visible Speech measurement
Press START/STOP to start measurement. Begin speech signal.
Open Fit Hearing Aids
Coupler measurements: Use our new
Open Fit Coupler!
 Real-ear measurements: Same protocol
but disable the reference microphone
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Open Fit Coupler
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Insert the hearing aid
into the coupler as
you would into the ear
No sealing is
necessary
Produces a frequency
response more like a
real-ear response
For ANSI
measurements to
specifications, use HA1 coupler
Real-ear Measurements
Some Open Fit hearing aids interfere with
the reference microphone measurement
outside the ear (feedback management
and/or amplified signal escaping from ear)
 Disable the REF MIC setting in the real-ear
measurement screen local menu
 Test as usual
 Expect very little amplification below 1000
Hz. Fit to target only in mid-to-high
frequencies
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Example of Open Fit Real-ear
Using the FONIX NOAH Module
Friendly Windows-based interface
 Automatically use NOAH audiogram
 Can send NOAH audiogram to analyzer
 Perform real-ear and coupler
measurements from computer
 Save all results into NOAH database
 On Top window: Perform real-ear while
adjusting the hearing aid!
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Interface
Now for a FONIX NOAH Module
Demonstration!