Presentation on theme: "Viewer’s notes ... to help you …"— Presentation transcript:
1 Viewer’s notes ... to help you … At the bottom left of each page there is a page number, when the slide has finished an automated sequence a small star appears in the bottom right hand corner to indicate that the slide may be ‘advanced’ when you are ready.To run the presentation:1. Click on the screen to make sure that the presentation window is selected.2. Use the space bar to advance (page up should reverse)
2 Introduction to the FP35 Hearing Aid Analyzer v6.01 Software Kristina FryeFrye ElectronicsWelcome to this presentation on the FP35 portable hearing aid analyzer! This presentation is part tutorial and part demonstration of the features of the FP35 analyzer. See for more specific step-by-step instructions on operation of the FP35 analyzer.
4 The FP35 offers: Quick & accurate coupler measurements An intuitive but versatile user interfaceOn-screen pop-up help windowsMultiple options for stimuli and measurement settingsBuild-in thermal printer and RS232 capabilityOptional real-ear measurements
6 Optional Accessories Include: Soft computer style carrying caseThere are a number of optional accessories available as well, including:A hard but lightweight brief-case style or a soft-sided carrying case, a swing-arm speaker to give you more flexibility in heights and angles for real-ear measurements, insert earphones for RECD and audiometric measurements, a larger, non-portable external sound chamber for better sound isolation and hearing aid positioning, and a child-sized earhook if you do pediatric real ear measurements.
8 Basic analyzer features: Automated ANSI or IEC test sequenceCoupler MulticurveUp to 4 response curves in dB Gain or dB SPLHarmonic and intermodulation distortionFour types of pure-tone sweepspure tone sweep audio demonstrationAbility to set custom default settingsEach FP35 comes with an automated test sequence. ANSI is the default sequence available. The European IEC, the Japanese JIS, and the Indian ISI standards are also available. You can also run individual frequency responses and distortion measurements in the Coupler Multicurve screen.Three types of pure-tone sweeps are available on each FP35. NORMAL delivers a standard frequency sweep contain many different data points. FAST is a repeating shorter sweep that measures 16 different frequencies repeatedly. SHORT is a burst of 10 frequencies that are presented very quickly. It is normally used for checking real-ear SSPL.The FP35 lets you set up to three different default configurations. This is particularly useful when switching between aids of different technology levels. Use one setup for testing analogs and another setup for testing digitals.
9 Composite/Digital Speech features (Now included standard) Composite: Broadband signal consisting of 79 different frequencies presented simultaneously, updating up to five times a second- audio demonstrationDigital Speech: Modulated Composite signal for testing digital hearing aids with noise suppression technologyICRA, ANSI, LTASS (DSL) speech weighting options with Composite & Digital SpeechThe Composite and Digital Speech signals are appropriate for testing digital hearing aids.
10 Function Keys [F1] to [F5] Basic OperationPrintHelpResetThe front panel buttons on the left side include:“print”, “help”, “reset”, and “operate” (which is basically the on button), and on the bottom there are 5 function keys that are labeled [F1] through [F5].“Operate” (On)Function Keys [F1] to [F5]
11 Basic Operation Menu Exit Back Next “Arrow” Keys Start/Stop The buttons on the right side of the front panel are: “menu”, “exit”, “back” and “next”, 4 arrow keys, and a “start/stop” button”.Start/Stop
12 Front-panel Buttons to remember [MENU] : Enters/exits local menus[NEXT/BACK]: Moves between related measurement screens and between main & advanced menus“Arrow” keys: Moves cursor through choices, or to adjust frequency/level[START/STOP]: Starts/stops selected function[EXIT] : Exits current screen, keeping curves[RESET]: Exits and clears data, resetting analyzerNow let’s review the key front-panel buttons:“Menu” as the name implies, enters or exits the menu relevant to the current screen you are in. All the menus in the FP-35 are pop-up menus that are overlaid on the screen.The “next” and “back” buttons are used to move between the main menu and more advanced menu options.The arrow keys, depending on the screen, can move the cursor through choices, or adjust frequency and level of the stimulus used during measurements.The “start/stop” button starts or stops a selected function such as a measurement.The “exit” button exits from the current screen, but also saves the data on that screen,while the “reset” button exits, but clears the data that were collected.
13 Function Keys – F1 through F5 Function keys vary from screen to screen but are always labeled above the F keye.g. pressing [F2] in the Opening screen takes you to the “Real Ear Audiogram” screen if available.The operations that the 5 function keys control varies between screens but they are always labeled at the bottom.As an example, shown here is the opening screen of the FP-35, and the [F2] key selects the Real Ear measurement and Audiogram mode, while [F3] selects Coupler Multicurve and [F4] selects ANSI 96.F1F2F3F4F5
14 Function Keys (Continued) Holding down a key will offer a pop-up menu - use arrows and ‘START’ to selectRepeated presses rotate through selectionse.g. in the Coupler Multicurve screen, [F4] selects the source type for measurementRepeated presses of function keys on some screens rotates through selections available, or you can hold the key down a few seconds to get a pop-up function key menu as shown here.Shown here is the Coupler Multicurve screen, where [F4] selects the source type for measurements.F4
15 Local MenusEvery measurement screen has a local menu containing settings for that screenShown here is the local menu for the coupler Multicurve screenAs shown here, you can reach a relevant pop-up menu from any screen. This shows the main menu choices for the Coupler Multicurve mode. You can choose whether to display in gain or SPL., the numerical or curve data, and so on.
16 Additional Menu Choices Some screens have additional menu choices. Use [NEXT] and [BACK] to move between the menus.Shown here is the Advanced Menu in the Coupler Multicurve screenSome screens have additional, advanced menu choices chosen using the “next” and “back” buttons. Shown here is the 1st of 2 advanced menu choice screens in Multicurve mode. This allows more advanced functions like auto-scaling, filtering, etc.
17 Onscreen HelpPop-up help windows can guide you through steps available in the current screenShown here are help steps for the Real-Ear Audiogram Entry screen if availableFinally, a very useful feature of the FP35 is the pop-up help that is available for each screen to guide you through the steps you need to take in the displayed screen. For example, shown here are help steps for the Real Ear Audiogram Entry screen. It shows you what keys to press to begin a new client, enter an audiogram, generate a target, and etc.
18 Coupler Configurations Overview of testing a BTEThe FP35 analyzer has a built-in sound chamber. Coupler measurements are usually performed using one microphone.
19 Proper Setup for Testing a BTE Velcro in the sound chamber and on the coupler assists in keeping the unit in place during measurement - center the BTE microphone over the loudspeaker.HA-2 coupler with BTE adapter.This slide shows the proper set-up needed in the sound chamber for testing a BTE hearing aid using the HA-2 coupler with BTE adapter. Velcro in the sound chamber and on the coupler assists in keeping the unit in place during measurement, once you have the hearing aid microphone centered over the loudspeaker in the sound chamber.
20 Proper Set-Up for Testing an ITE Be sure “leaks” aresealed, or will haveexcessive 500 Hz gainThe set-up for an ITE or ITC is shown here. The unit is sealed with “fun tak” inside the HA-1 coupler. Be sure that all “leaks” are sealed or you will give excessive gain at 500 Hz due to turning it up to compensate for energy lost to this artificial venting.
21 ANSI SFor quality control to ensure dispensed hearing aids match manufacturer’s specsCompared to previous standard it offers:Multiple I/O and attack/release measurementsAGC aids tested at reduced reference test gainFrom the Opening Screen, press [F5] or [F4]One of the main measurements typically done for quality control purposes is a standard ANSI S test sequence. It is used to ensure that hearing aids you dispense acceptably match the manufacturer’s specs. If they don’t, they should be returned to the manufacturer.
22 Reminder:Level the sound chamber daily, or if room noise changes.ANSI 03 SetupPress [MENU] to open local menu. Use arrow keys to make selections.Pressing the “menu” button allows you to designate “ear”, for labeling printouts, and to make other selections such as noise reduction or turning off EIN, etc.Pressing the [F1] key from the main ANSI 03 screen cycles between choices for linear hearing aid, AGC hearing aid, and adaptive AGC hearing aid.As a reminder, you should level your sound chamber daily, or anytime you feel the room noise has changed enough to impact measurements.F1: Choose Aid TypeF2 & F3: Select I/O freq to test
23 ANSI 03 Results (AGC Aid) Output (OSPL90) Curve Average & Max Output Full On & Ref Test GainsOutput (OSPL90) CurveEq. Input NoiseFrequencyRangeShown here is a sample of ANSI ‘03 results using an AGC hearing aid. You can see the maximum output (OSPL-90) curve, the frequency response curve, and along the right side all the numerical values are displayed, including:Average and max of the OSPL-90 curve, The full-on and reference test gains, Equivalent input noise, Frequency range information, and harmonic distortion.Frequency ResponseCurveHarmonicDistortion
24 ANSI 03 Results (continued) Input/Output CurvesI/O CurvesKeyANSI 03 results for an AGC aid also can include multiple input/output curves, as shown here.The key in the box designates the frequency used for each.
25 Coupler Multicurve Screen Choose stimulus of pure tone (sweeps or single frequency), Composite, or Digital SpeechMeasure/display a family of up to 4 frequency response curvesShow graph or data numerical valuesMeasure/display harmonic and intermodulation distortionThe Coupler Multicurve Mode also comes standard with the FP35.You can use it with pure tones, composite noise, or the digital speech stimuli, and it measures and displays a family of up to 4 frequency response curves on the same screen.You will typically want to display the curves themselves but you can also show a data print-out of numerical values for a curve.Also, the FP35 allows you to measure and display both harmonic distortion and intermodulation distortion.
26 Coupler Multicurve Screen AmplitudeThe Coupler Multicurve screen is most commonly used for measuring frequency response curves. The source type is selected with the F4 key. Four types of pure-tone sweeps, the Composite, and the Digital Speech signals come standard with the FP35. Use the up-down arrow keys to adjust the source amplitude. To measure another curve, choose a new curve number with F2.As shown here, in Coupler Multicurve Mode, [F2] selects the curve, [F3] turns the display of a curve off and on without deleting the measurement, and [F4] changes the source signal. Again, it’s very intuitive and straightforward once you’ve had a few moments to play around hands-on with the instrument.F1–Delete curveF5 - LevelF3 –Turn curve on/offF2 –Select curveF4 – Select source type
27 Coupler Local MenusA useful option in the local ‘MENU’ is to switch between Gain and SPL display.A second ‘Advanced’ menu is accessed using ‘Next’ key.In the local menu, you can switch between dB Gain and dB SPL (all measurements are converted), change the display from graphical to numerical, and turn on the harmonic distortion measurement.
28 Pressing ‘help’ explains the abbreviated curve codes Family of CurvesThis curve family shows linear amplification up to 60 dB and compression from 60 dB through 90 dB SPLCurve boxThese curves were taken with the Composite signal at 50, 65, 75, and 90 dB SPL and reveal a great deal of compression across the entire frequency band.Pressing ‘help’ explains the abbreviated curve codes
29 Another Family of Curves This curve family shows no compression between 50 and 70 dB SPL with output limiting starting at 80 dB SPL for this high gain hearing aidThese curves were taken at 50, 60, 70, and 80 dB SPL with the Digital Speech signal. Since curves 1-3 fall on top of each other, you can tell immediately that the aid is acting linearly between those levels.
30 Testing Digital AidsSome DSP aids have NR circuitry that reduces gain when the input signal is noiseThe composite signal, because it is continuous and non-modulating, is seen by the circuitry as “noise”Thus, gain is reduced in the aid while the composite signal is on, and thus the measurement is not accurateThe Composite signal in the Multicurve screen can be very useful in fully characterizing the output and processing of a hearing aid. However, there is a problem with using the composite signal with some digital signal processing hearing aids.Some DSP aids have noise reduction circuitry that reduces gain when the input signal is judged to be noise.The Composite signal, because it is continuous and non-modulating, is unfortunately seen by the circuitry as “noise”.Thus, gain is reduced in the hearing aid while the composite signal is on, and thus, the measurement is not accurate.
31 A Solution: The “Digital Speech” Signal Switches Composite signal on/off intermittently in burstsThe “on” time can be set from 50 to 150 msec and the “off” time is randomly varied between 100 msec and 300 msecThus, the hearing aid responds as if the input is speech instead of noise (i.e., modulated instead of continuous)ANSI, ICRA, and LTASS speech weightings are available with this stimulus tooRecently improved to test aids with feedback suppression!A solution for those DSP hearing aids is to use the “digital speech” signal.This switches the composite signal on and off intermittently in bursts. The “on” time can be set from 50 to 150 msec*, and the “off” time is randomly varied between 100 and 300 ms.Thus, the hearing aid responds as if the input is speech instead of noise, because the signal is modulated instead of continuous.Both ANSI and ICRA weightings are available with this stimulus too.
32 Example using DSP Aid ICRA Spectra ANSI Spectra Composite Signal An example of the differences you might see in frequency response curves for a Widex Senso DSP hearing aid is shown here.You can see that both the ICRA or the ANSI spectra with the digital speech signal show higher gain than when using the composite signal - - because the NR function kicked in during the composite stimulus measurement. In this example, the ICRA Digital Speech signal produces more gain in the higher frequencies than ANSI because the signal contains less energy in the highs. The compression setup on the hearing aid turns up the gain more to compensate for the low output of the high frequencies. Not all hearing aids will react to the signal in this manner.The digital speech signals more accurately represent the gain that the hearing aid will supply for speech signals, while the composite noise actually represents the gain that the hearing aid would supply for a broadband noise after the NR circuitry has kicked in.The Digital Speech signal has recently been improved to make it a better test signal for hearing aids with noise suppression technology.CompositeSignal
33 Battery Current DrainPlug the battery pill into the interior side of the sound chamberBattery current measurements will be automatically enabled
34 Harmonic Distortion Test Harmonic distortion can be measured during any pure-tone sweep by setting the DISTORTION type in the local menu to 2ND, 3RD, or TOTAL.Distortion scaling on right side of graphYou can set DISTORTION in the local menu to 2ND, 3RD, or TOTAL. This will perform a harmonic distortion measurement during a pure-tone sweep. Harmonic distortion is represented by a series of bars under the frequency response. If the hearing aid has very low or no distortion, you may not see any bars at all.
35 Frequency Shifting Hearing aids Some hearing aids “compress” the frequency response of the input signal in order to amplify at frequencies where the patient has residual hearingThe DIG FS input signal produces a pure-tone signal and measures the response across the entire frequency band so you can see where that signal is being amplifiedThe FP35 has a test for measuring frequency shifting hearing aids. This is a special input signal called DIG FS.
36 Frequency Shift Test Dotted line represents the input signal The DIG FS test defaults to 4000 Hz, but can be changed to any frequency between Hz in 100 Hz intervalsUse F4 to select DIG FS and test the hearing aid as usual (press START/STOP to start and stop the measurement). The dotted line represents the frequency and level of the input signal. The measurement curves gives the frequency response of the hearing aid to the signal from Hz. This allows you to see which frequency is being amplified by the frequency-shifting hearing aid.The aid shifts the peak to 3000 HzF4 – Select DIG FS
37 Intermodulation Distortion Test IM distortion can be measured by setting the IM FREQ DIFF in the advanced menu. This will create the DIST source type selectionThe IM test presents two tones simultaneously. The frequency difference between the two tones is set by the user in the advanced menu. When the DISTORTION selection in the main local menu is set to 2ND, 3RD, or TOTAL, you can sweep these two tones across the frequency spectrum and get the IM distortion as a percentage of the total signal.F4 – Select DIST type
38 Numerical Data Display To display numerical data select DATA in the DATA/GRAPH selection in the local menuYou can view the numerical data of the selected curve by toggling the DATA/GRAPH selection in the local menu.
39 CIC Option Set the COUPLER TYPE to CIC in the local menu. CIC coupler HA-1 couplerThe CIC coupler cannot be used to check the manufacturing specifications of a hearing aid, but it can be used for a more accurate coupler measurement of a CIC hearing aid. CIC Coupler and software corrections are used to create more accurate coupler measurements of CIC hearing aids.
40 Open Fit CouplerThe Open Fit coupler provides a more realistic frequency response than a 2-cc coupler and it’s easier to attach to the hearing aid.The Open Fit coupler is used to produce a more realistic frequency response curve with easier coupling than can be obtained with a standard 2-cc coupler.
42 The FP35 Real Ear Basic: Integrated probe microphone Calibration adaptorsExtension pole for speaker
43 Optional Real-ear Accessories Infant headband setSwing-arm speakerInsert earphones and calibration adaptor for RECD
44 Real-Ear features:Fitting rules: NAL-NL1, MOD NAL, DSL, NAL-RP, plus the traditional onesAge correction factors for testing kids with NAL-NL1 and DSLInsertion Gain & SPL-o-gram methodsVisible SpeechCoupler Target & Simulated Real-earRECDMany people also order the real-ear option, which lets you perform probe microphone measurements on their patients and see how the aid is responding inside the patient’s ear. The FP35 analyzer has the latest fitting formulas including NAL-NL1 (non-linear), DSL WDRC, DSL LIN, and NAL-RP (linear).You can perform your real-ear measurements using the SPL or the insertion gain method. Any measurement taken in one screen is automatically translated to the other screens, so it’s easy to switch back and forth between the two views.If desired, you can perform a real-ear-to-coupler difference on your patient. This creates coupler targets appropriate for your patient’s hearing loss and thus lets you fit the hearing aid using a coupler. This method is useful in pre-fitting before the patient comes into the office, and in fitting aids on infants and small children.
45 FP35 Real-ear Screens Audiogram entry screen Real-ear SPL screen Unaided & aided screenInsertion gain screenThere are four real-ear screens. Press F2 from the Opening screen to enter one of them. By default, the Audiogram Entry screen is the first screen to appear. Use the [NEXT] and [BACK] keys to move between the other screens.Use the [NEXT] and [BACK] keys when in Real-ear Mode to cycle between these four screens.
46 Real-ear Configuration Use Built-in speakerOr use Optional external speakerYou can perform REM with either the built-in real-ear speaker or an external speaker on a floor stand or swing arm.
47 Audiogram Entry Screen AmplitudeThe Audiogram Entry screen is used to enter the patient’s audiogram and generate an appropriate target. You can also perform a measured RECD in this screen.FrequencyF2 – Select HTL/UCL/BoneF3 – Generate Target
48 FeaturesFitting rules: NAL-NL1, MOD NAL, DSL, NAL-RP, plus the traditional onesAge correction factors for testing kids with NAL-NL1, MOD NAL, and DSLRECD
49 NAL-NL1 & MOD NAL Features Age of client (kids)Number of channelsBone conductionBilateral vs. Unilateral lossLimiting: Multi-channel or WidebandCompression thresholdAll of these are settable in the Target Menu – from the Audiogram Entry screen, press [MENU] and then [BACK].
50 Generating the Selected Target Press [F3] to generate the targetPress [F5] to toggle between IG target and SPL targetShown here is IG TargetAfter entering the audiometric information for the patient, pressing [F3] generates the target gain for the selected formula.Pressing [F5] toggles the display between insertion gain target and the dB SPL aided target.Shown in this example is the insertion gain target.Below the box on the right side of the screen, you can see that this is for the left ear of an adult patient being fitted unilaterally with a single-channel AGC hearing aid with a compression threshold of 50 dB SPL, using the NAL-NL1 prescriptive approach.Inter-F3F5Note: No curves are measured in the Audiogram Entry screen
51 Set-up for Real Ear Measures Internal sound chamber converts to sound field speaker; should be ear heightRecommend position patient 12” from the speaker at 45° angleStand away from the patient/loudspeaker during measurementsShown here, then, is the physical FP35 set-up for real ear measures.The internal sound chamber is converted to a sound field speaker, which is placed at ear height. You can also use another external speaker if portability is not important.It is recommended that you position the patient’s ear 12 inches from the loudspeaker at a 45-degree azimuth.You should always stand away from the patient and the loudspeaker during measurements, so that your own body doesn’t act as a baffle. I prefer to stand behind the speaker.Probe
52 Proper Placement of Microphones RefMicProbe tube:marked 30 mmfrom the tip for Adultsand 25 mm for childrenThis illustrates proper placement of the microphones on the ear.The reference mic is attached to the integrated probe microphone and placed above the ear. The probe tube can be marked at 30 mm from the tip for adults, and about 25 mm for children depending on their size, so that insertion depth is adequate without causing pain by bumping the eardrum. Marking the tube with a red pen also serves as a means to make sure insertion of the hearing aid doesn’t push the tube in farther. The probe tube should exit at the inter-tragal notch.
53 Leveling the Sound Field Loudspeaker Position patient and earhook/microphone (probe tube insertion optional)Go to REM test screen (Real-ear SPL, Real-ear Unaided & Aided, or Real-ear Insertion Gain) using [NEXT] and [BACK].Press “Level” [F5] and [START/STOP]Leveling only uses the reference microphone so probe placement doesn’t matterThe hearing aid can be inserted in the ear during leveling as long as it is turned off.Leveling the sound field speaker is imperative, for each patient and each ear, in order to obtain accurate measurements.Position the patient with the earhook and reference microphone in place. Note that insertion of the probe tube is optional at this point since because the probe microphone is not used in the leveling process.Stand away from the loudspeaker field, and select [F5] to activate the leveling signal.Success will be indicated by a straight line and the word “level” on the screen.Reminder: Re-level for each patient and each ear
54 Real-ear SPL Screen UCLs Target (*) HTLs Amplitude START/STOP The Real-Ear SPL screen displays the patient’s threshold values, real-ear target, and uncomfortable levels all in one screen in dB SPL.Use F2 to select the curve to measure. Use F4 to select the source type. Use the up-down arrows to change the input level. Press START/STOP to start and stop the measurements.HTLsSTART/STOPF2 – Select CurveF4 – SelectSource Type
55 Real-ear SPL Measurements Goal:Aided 3 below UCLsAided 2 meet targetAided 1 above HTLsIn a typical hearing aid fitting, AIDED 1 is used at to make sure that soft sounds meet the patient’s threshold values. AIDED 2 is used to make sure medium speech meets the target. AIDED 3 is used to make sure that loud sounds are below the patient’s uncomfortable levels.
56 Visible SpeechUse Live Speech or Pre-recorded Speech from an attached CD player or iPodSet the source type to COMP (or DIG SPCH) with F4Set the source level to OFF using the down-arrow key repeatedlyPress START/STOP to start the measurementThe Real-ear SPL screen can be used to perform Visible Speech measurements using live voice or a pre-recorded signal from an external source. If you have a supported FP35, you can connect a CD player or an iPod to produce the external source through the FP35 speaker. To perform Visible Speech, set the source type to COMP and use the down arrow key to set the source to OFF. Press START/STOP to start the measurement.
57 Visible Speech Setup with External Signals This is the setup for connecting the FP35 to an external source (supported FP35 only). The external source is connected to the “Line in” connector. When spectrum analysis is performed, the external source plays through the FP35 speaker. If your FP35 does not support this setup, you can use an external speaker connected a separate audio system.iPod or CD player
58 Visible Speech Testing REF = Input signal levelPeak Pulsed average (diamonds)Live Speech testing can be performed by setting the source type to COMP and using the down arrow key repeatedly to turn source amplitude all the way OFF. This puts the analyzer in spectrum analysis mode. The diamonds in this display indicate the peak-pulsed average values of the measured speech. The REF mic reading gives you the level of the input signal and can be used to calibrate an external input.Source OFFReal-time curveF2 – Select AIDED curveF4 – COMP or DIG SPCH
59 Third Octave analysis Two SPL analysis methods are available: 100 Hz FFT SPL: 79 measurement points every 100 Hz3RD Octave SPL: 17 measurement points unequally spaced with higher resolution in the low frequenciesThird octave analysis has recently been added (v6.00) to the existing 100 Hz FFT analysis method. Third octave analysis produces SPL measurement curves with more output but less resolution. This creates the illusion of smoother curves because there is less data being graphed.
60 100 Hz FFT vs Third Octave Analysis 3rd Octave analysis produces measurement curves that are 3 dB per octave greater than 100 Hz FFT curves. However, this is a result of the measurement resolution, not the inherent energy in the hearing aid. As long as both measurement curves and target curves are consistent, it doesn’t really matter which analysis method is used. But the third octave analysis is better if you are comparing test results with competing equipment that also uses 3rd octave analysis.100 Hz FFT analysis
61 First: Thought Experiment 100 Hz vs 50 Hz Analysis Think of the output of a frequency response as energy.Each point on the response is a “bin.”More bins = better resolution, less output per binTo explain why 3rd octave analysis produces higher output results, think of the difference between FFT analysis at every 100 Hz with FFT analysis at every 50 Hz. The 50 Hz analysis gives much better resolution, but less energy per point. This makes sense if you think of the sound energy as water filling up buckets. More buckets means less water (output) per bucket. Fewer buckets means less resolution but more water per bucket. 3rd octave analysis vs 100 Hz analysis is similar. There are only 17 points in 3rd octave analysis, but 79 point in 100 Hz FFT analysis. This gives 3rd octave analysis more energy per point, but less resolution so you can’t see what is going on in the hearing aid response between the measurement points.
62 100 Hz FFT Analysis vs Third Octave In Third Octave analysis, frequency response is divided into 17 different points: 200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1600, 2000, 2500, 3150, 4000, 5000, 6300, and 8000Third Octave analysis has better resolution in the low frequencies and less resolution in the high frequencies due to logarithmic scalingAll FONIX analyzers perform “100 Hz FFT” analysisFrequency response is divided into 79 different points that are 100 Hz equidistant (200, 300, 400… 7900, 8000 Hz)Difference between 100 Hz FFT and Third Octave analysis is 3 dB per octave
63 Important NotesThis 3 dB per octave difference only occurs when viewing results in terms of dB SPL (coupler or real-ear). Gain measurements are not affected.This difference only occurs when using broadband signals. During a pure-tone sweep, only one “bin” is filled at a time, so the energy is not distributed.
64 Third Octave analysis on the FP35 analyzer Available in Real-ear SPL and Coupler Multicurve test screens.The Display setting is used to choose between 100 Hz FFT and 3rd Octave SPL analysis.
65 Auto TestWhen enabled, it measures all three aided measurement curves sequentiallyThe measurement time for each curve can be changed in the Advanced MenuThe “unaided” curve is not part of the Auto Test Sequence
66 Auto TestEnable Auto Test in the local menu. The Auto Duration setting is in the advanced menu (NEXT)
67 Insertion GainAided & Unaided screen shows aided and unaided measurements in dB Gain or dB SPLInsertion Gain screen shows resulting insertion gain curve & insertion gain target
68 Aided & Unaided Screen Aided 1 Unaided The operation of this screen is identical to the operation of the other measurement screens. The unaided and aided measurements are displayed in dB Gain (no targets are available in this screen). Up to three different aided measurements can be taken.
69 Insertion Gain Screen IG Target IG measured curves Use this screen to match the hearing aid to the insertion gain target. Use [NEXT] and [BACK] to easily switch between the Unaided & Aided screen and the Insertion Gain screen.
70 Directional Hearing Aids Perform two measurements: one with the speaker in front of the patient, the other with the speaker behind the patientUse the Unaided & Aided screen for showing forward and reverse measurementsUse the Insertion Gain screen for showing directional advantage
72 Directional Advantage This aid shows more directional advantage in the high frequencies than in the low frequencies.
73 Coupler Targets Audiogram entered in Audiogram Entry screen, as normal RECD – Average or MeasuredCoupler Target screenCoupler EarSim screen
74 Real-ear to Coupler Difference (RECD) The acoustical difference between the 2-cc coupler and the real-ear unaided response on a patient (as measured with insert earphones)Two measurements are needed:The coupler measurement: Performed in the Calibration screen only periodicallyThe real-ear measurement: Performed in the Audiogram Entry screen for each patient measuredThe RECD is the acoustical difference between the 2 cc coupler and the real-ear unaided response for an individual patient.There are 2 measurements needed to determine RECD.The first is the coupler measurement, which is actually already done when you calibrate the insert earphone to be used in the measurement. The values are then stored in the FP-35’s permanent memory.The second is the patient measurement:For this, either a custom earmold or a foam eartip is coupled to the insert earphone and placed over the probe mic in the patient’s ear. This measurement is performed in the Audiogram Entry screen.
75 RECD Coupler Physical Setup Insert coupler microphone into HA-2 couplerConnect insert earphone to HA-2 couplerPlug insert earphone into the back of the FP35 analyzer in the plug marked “Earphone.”
76 RECD Coupler FP35 Operation Press [MENU] from the Opening screen to enter the Default Settings screenPress [F3] to go to the Calibration ScreenPress [F4] to go to the Earphone Calibration ScreenPress [START/STOP] twice to perform the measurementPress [F5] and [START/STOP] to save the coupler RECD.Use the down arrow to select Calibrate Ins. Earphone (RECD) and repeat steps 4-5.
77 RECD Real-ear Physical Setup Insert probe microphone into earInsert insert earphone into earMarked 30 mmfrom the Tip for Adultsand 25 mm for childrenProbe
78 RECD Real-ear FP35 Operation Go to Audiogram Entry screenUse F2 to select the RECDUse F3 to set MeasurePress [START/STOP] to perform the real-ear measurementResults are displayed in numerical and graphical format. The RECD is automatically used in all relevant conversions.Here is the result screen. The RECD is displayed in graphical format in dB gain as well as numerical format in the data table.The measured RECD values are used to obtain an accurate coupler target in the Coupler Target and Coupler Multicurve screens.If you have previously measured the RECD, you can use the arrow keys in the screen to input the values manually.ProbeF2 – Select RECDF3 – Select Measure RECD
79 Coupler Measurements with Targets Coupler Target screen: Converts real-ear targets into coupler targets for comparison with coupler measurementsCoupler EarSim screen: Converts coupler measurements into simulated real-ear measurements for comparison with real-ear targetsTwo ways of looking at the same info
80 Coupler Target Screen Converted target Coupler measurements In this screen, the real-ear targets are converted into coupler targets and compared directly to coupler measurements. You can perform up to 4 different frequency responses in this screen. Results and targets can be displayed in dB Gain or dB SPL.
81 Coupler EarSim Screen Real-ear target Simulated real-ear measurements In this screen, the targets displayed are actually real-ear targets. Any coupler measurements you take are converted into “simulated real-ear” so that they can be compared directly to the displayed target. Targets and measurements can be shown in dB SPL or dB insertion gain.Simulated real-ear measurements
82 Entering default settings The FP35 can memorise up to 3 default settings groupsTo enter your default settings choose ‘MENU’ from the initial FONIX screen‘NEXT’ will advance to a second screen
83 Default Settings Screens If you press the “menu” button from the Opening screen, you can change the default settings menu to your “most often used” choices for many measurement parameters. Use F5 to save the displayed settings to a setting group. Use F2 to load that setting group. In addition to the two default screen displayed here, there is one more screen that, among other things, allows you to change the default source type.Settings groups are useful if you have more than one clinician in an office and each likes to use the analyzer in different ways. They can also be used for different hearing aid technology levels. For instance. Setting #1 can be used for digital hearing aids, and sets the source type to digital speech. Setting #2 might be used for analog hearing aids and sets the source type to Composite.F2: Change setting groupF5: Save setting group
84 Choosing settings group The settings group may be chosen at the initial screenYou can also quick change to another user group by using the F1 key in the Opening screen.F1: Change setting group
85 Please email firstname.lastname@example.org should you require further information. Thank you for your time!Please should you require further information.Frye Electronics, 9826 SW Tigard St, Tigard, OR 97223, USATel: orSpecial thanks to David Evans of Connevans, UK and Dr Carol Sammeth who contributed to this presentation