Printing and Storing Results...25 Section overview...25 Internal printer paper loading...26 Barcodes, headers and comments on printouts ...27 Local printer setup...27 Printing to a USB memory stick ...28 Network printer setup ...29 0611 RM500SL User’s Guide Version 2.8 Table of Contents Page 2...
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Section overview...50 10.2 REM calibration facts ...50 10.3 Calibration of REM probe microphone ...51 10.4 Calibration check for probe module ...52 10.5 Max TM SPL setup...53 10.6 ABR nHL to eHL setup ...53 0611 RM500SL User’s Guide Version 2.8 Page 3...
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DSL 5.0 changes ...72 17.5 NAL-NL1 in Speechmap...72 17.6 Using Speechmap...73 17.7 Screen tour – unaided screen...74 17.8 Screen tour - aided screen ...74 17.9 REM or S-REM mode...75 17.10 SII calculation in Speechmap ...76 0611 RM500SL User’s Guide Version 2.8 Page 4...
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No REM ref. mic. detected ...91 20.10 Invalid REM calibration...91 20.11 REM speaker overdriven...92 20.12 Barcode scanner malfunction ...92 Technical Specifications ...93 Glossary...94 References...98 Appendix 1: AudioNote 2.1 VERIFIT and RM500SL Test Signals and Analysis...101 0611 RM500SL User’s Guide Version 2.8 Page 5...
10: Real-Ear Measurement Setup 11: REM Screen Setup In addition you will find a glossary, references and more information in the electronic user’s guide on the Audioscan software CD. FastFacts 1.1: RM500SL Help topics 0611 RM500SL User’s Guide Version 2.8 ®...
PC. To run FoxitReader.exe double click it. 4) To view the User’s Guide, double-click the RM500SLUsersGuide.pdf file. The User’s Guide may also be downloaded from www.audioscan.com. FastFacts 1.3: Electronic users guide 0611 RM500SL User’s Guide Version 2.8 Page 7...
Email: info@audioscan.com service@audioscan.com Warranty: The RM500SL is warranted against defects for two years from date of purchase. Within this period, it will be repaired without charge for parts, labor or return shipping when returned prepaid to your authorized Audioscan service agent.
RECD transducer connected. The use of other accessories may result in increased emissions. Guidance and manufacturer’s declaration - electromagnetic emissions The RM500SL is intended for use in the electromagnetic environment specified below. The user of the RM500SL should assure that it is used in such an environment. Emissions test Compliance...
2.7: External printer, auxiliary audio outputs FastFacts 2.1: Getting started Unpacking and connecting 1) Carefully unpack the RM500SL and check the contents of the shipping box against the enclosed packing list. Note that some parts may be packed inside the test chamber.
NOTE: A microphone extension cable (VA-130) is available from Audioscan. Standard audio extension cables should not be used. They will substantially increase noise levels. FastFacts 2.3: Microphone connection 0611 RM500SL User’s Guide Version 2.8 Page 11...
3) DO keep the probe module and probe tubes in a clean area. 4) DO stow the probe module when not in use or when transporting the RM500SL. FastFacts 2.4: Microphone care Battery pill use and care Battery pills are optional.
Mouse, keyboard, barcode scanner The RM500SL may be operated from the built-in keypad, a USB mouse (not included) or a standard USB computer (QWERTY) keyboard (not included), which may also be used to enter headers and comments on printouts: See 3.2 Input...
General Operation Section overview The RM500SL is operated by using the built-in keypad, a USB QWERTY keyboard (not included) or a USB computer mouse (not included). Any of these pointing devices can be used to select items from menus, operate on-screen buttons and to enter audiometric data.
Input device operation The RM500SL may be operated by means of the built-in keypad, an external mouse (not included) or an external QWERTY keyboard (not included). These devices are used to summon on-screen menus and select items from them, to operate on-screen buttons and to input data.
Barcode data input In Speechmap and Insertion gain tests, audiometric data in barcode form on a RM500SL or Verifit printout may be entered by scanning the appropriate barcode. In Speechmap, threshold, UCL, RECD, transducer, age and ABR nHL to eHL conversion factors are encoded.
<Help> Summon context-sensitive Help Screen. <Setup> Summon Setup Menu containing a list of RM500SL features that can be modified. Any modifications made will be maintained after power off. <Tests> Summon Test Selection Menu containing a list of the available test procedures.
The current list item is shown in the window . When selected, a Toggle Button alternates between states. The current state is shown in the window. FastFacts 3.5: Menus, lists and buttons 0611 RM500SL User’s Guide Version 2.8 Page 18...
CD-ROM and must be transferred to the USB flash drive in order to be used. This requires that the USB flash drive be removed from the RM500SL and plugged into the USB port on a PC that has a CD-ROM drive.
Software updates, along with a new User’s Guide, are shipped on a CD-ROM. The software must be transferred to the USB flash drive in the RM500SL in order to be used. This transfer requires a PC with a CD-ROM drive and a USB port. To...
Speechmap and Insertion Gain tests. To enable/disable this feature: 1) Press <Setup>, then highlight and <PICK> [Test setup] 2) Highlight and <PICK> [Save test setup] to toggle between Yes and No. FastFacts 4.4: Saving test setup 0611 RM500SL User’s Guide Version 2.8 Page 21...
Networking Section overview The RM500SL may be connected to a network using a Cat 5, RJ-45 cable. This allows screen images to be printed on a network printer or on a shared printer on a networked PC. Images and underlying data may also be saved to a shared folder on a networked PC.
5) Highlight and <PICK> [Test connection]. The RM500SL will prompt you for an IP address of a computer or router on your network. In a single PC-to- RM500SL network, this is the IP address of the PC you are connecting to. FastFacts 5.3: Networking setup 0611 RM500SL User’s Guide Version 2.8...
Ethernet network hub or switch. Connect a Cat 5, RJ-45 cable from a hub port to the RM500SL connector. To set up the PC: 1) Right click Network Neighborhood (or My Network Places) & select Properties.
6.4: Local printer setup 6.5: Printing to a USB memory stick 6.6: Network printer setup 6.7: Printing to a network file 6.8: Data storage to a network file FastFacts 6.1: Printing and storing results 0611 RM500SL User’s Guide Version 2.8 Page 25...
Thermal paper may darken if stored for prolonged periods at elevated temperatures and lose contrast if subjected to light. Keep long-term supplies and printouts in a cool dry place out of direct light. FastFacts 6.2: Internal printer paper loading 0611 RM500SL User’s Guide Version 2.8 Page 26...
Check [Black only] for black printouts on a color printer 7) Press <Continue> to exit printer setup and <Continue> to exit Setup. FastFacts 6.4: Local printer setup 0611 RM500SL User’s Guide Version 2.8 6.7: Printing to a Page 27...
Printing to a USB memory stick 1) Plug a USB memory stick into the USB port next to the product label on recessed panel. The RM500SL may be either on or off. 2) Press <Setup>, then highlight and <PICK> [Printing].
(or use the Enter key on the keyboard’s numeric keypad). Obtain needed information from your network administrator. FastFacts 6.6: Network printer setup 0611 RM500SL User’s Guide Version 2.8 Networking. To print to a printer on a Page 29...
<Session> and one of the [Erase data] choices or the power is turned off. (Setup data will be retained even after the power is turned off.) The RM500SL database may be saved as a delimited text file on a networked PC if network file printing has been set up. See 1) Press the <Session>...
To change the scale, highlight, then <PICK> [dB SPL] or [dB Gain] FastFacts 7.4: Output or gain scale 0611 RM500SL User’s Guide Version 2.8 7.8: HIT calibration facts 7.9: Calibration of HIT reference microphone 7.10: Calibration check for coupler microphone 7.11: Coupling the hearing instrument...
In the list of available frequencies, highlight and <PICK> the frequencies to be used to measure attack and release time. Press <Continue> to exit. FastFacts 7.7: ANSI test frequencies 0611 RM500SL User’s Guide Version 2.8 8.3: ANSI S3.22-2003 facts. Page 32...
Your calibration curve should be similar to one of these and should remain stable over time. Irregularities in the calibration curve may be the result of positioning errors. See 7.9: Calibration of HIT reference microphone. FastFacts 7.8: HIT calibration facts 0611 RM500SL User’s Guide Version 2.8 Page 33...
7.10: Calibration check for coupler microphone FastFacts 7.9: Calibration of HIT reference microphone 0611 RM500SL User’s Guide Version 2.8 See 7.8: HIT calibration facts for an additional check. Page 34...
94 +/- 1.3 dB. 11) To stop the measurement, highlight and <PICK> [Stop test]. FastFacts 7.10: Calibration check for coupler microphone 0611 RM500SL User’s Guide Version 2.8 7.9: Calibration of HIT reference Page 35...
7.11 Coupling the hearing instrument The RM500SL is supplied with 2 metal couplers, a type HA-1 (ITE) and a type HA- 2 (BTE). Note that an ANSI standard coupler for CICs does not exist. These must be tested in the HA-1 coupler.
3) Position the HIT reference microphone as close as possible to the (front- facing) microphone opening of the hearing instrument without touching it. 4) Close and seal the test chamber. FastFacts 7.12: Positioning the hearing instrument 0611 RM500SL User’s Guide Version 2.8 7.11: Coupling the hearing instrument care. >> Page 37...
Linear and AGC aids that have a HFA (or SPA) full-on gain greater than the HFA (or SPA) OSPL90 minus 77 dB. Otherwise the RTP is full on. If required, the RM500SL will pause in its testing and guide you in setting the gain control to the RTP.
6) Press <Continue> to run the test or press <Cancel> to abort the test. Note that, if required, the RM500SL will pause during the test to request that the volume control be adjusted to the Reference Test Position (RTP). Open the...
6) Press <Continue> to run the test or press <Cancel> to abort the test. Note that, if required, the RM500SL will pause during the test to request that the gain control be adjusted to the Reference Test Setting (RTS). If necessary, open the HIT chamber and, without moving the hearing instrument, adjust the gain control until the large vertical arrow on the screen prompt disappears.
In 2003 tests: Full-on average gain is measured with a 50 dB input SPL, average gain at RTS is always measured at 60 dB input SPL and the frequency response curve is always run at 60 dB input SPL. FastFacts 8.6: ANSI test results 0611 RM500SL User’s Guide Version 2.8 Page 41...
(particularly at 250 and 500 Hz). Ensure that the test chamber is well sealed and ambient noise is low. FastFacts 8.7: ANSI input-output curves 0611 RM500SL User’s Guide Version 2.8 8.2: ANSI S3.22-1996 facts instrument, 7.12: Positioning the hearing to prepare the instrument for 8.5: ANSI 2003 Linear and AGC tests...
ANSI telecoil terminology The RM500SL test chamber contains an integrated telephone magnetic field simulator (TMFS) meeting the requirements of ANSI S3.22, that enable the measurement of coupler SPL produced by a hearing instrument with a telephone pickup coil. ANSI uses the following terms in telecoil testing: RTG (reference test gain) is the average gain measured with the gain control in the reference test position (1996) or reference test setting (2003).
(HFA-or SPA) SPLITS value and run the SPLITS curve. 9) If an RTG has been previously obtained, the STS or RSETS will be shown. FastFacts 8.9: ANSI telephone simulator (TMFS) test 0611 RM500SL User’s Guide Version 2.8 tests; 8.5: ANSI 2003 Linear and AGC tests 8.4:...
Note that the 2003 standard requires that the telecoil test be performed with the AGC set for minimum effect. See 8.3: ANSI S3.22-2003 facts. The 1996 standard requires the manufacturer to specify the AGC settings used for the telecoil test. FastFacts 8.10: Telecoil test results 0611 RM500SL User’s Guide Version 2.8 Page 45...
Other Hearing Instrument Tests Section overview In addition to the tests of ANSI S3.22, the RM500SL provides the following: Distortion: Harmonic distortion at 2 levels varying from 60 – 90 dB SPL. Multicurve: 1 – 4 curves of coupler SPL or coupler gain for swept tones or pink noise in 1/12 octaves at selected input SPL of 0 or 40 to 90 dB in 5 dB steps.
4) See 7: Hearing Instrument Tests Setup FastFacts 9.4: Multicurve results 0611 RM500SL User’s Guide Version 2.8 instrument, 7.12: Positioning the hearing to prepare the instrument for octave bands. They will be to change screen appearance.
5) Highlight and <PICK> [Start test] FastFacts 9.6: Battery drain test 0611 RM500SL User’s Guide Version 2.8 octave frequencies. Pressing <Continue> causes the octave bands and displayed at 1/12 2.5: Battery pill use and care octave bands octave...
When set for a stimulus level of 0 dB (off), the Manual control mode allows the RM500SL to be used as a sound level meter. Sound at the HIT reference microphone and the coupler microphone may be analyzed by 1/12 weighted or C-weighted filters.
It is suggested that a copy of the calibration curves for the probe modules when new be posted near the RM500SL for comparison with daily or weekly curves. If there is a drift in calibration with time, the module may need replacement. See 10.4: Calibration check for probe...
± 5 dB. 7) To change the calibration interval, highlight & <PICK> [Daily] or [Weekly]. FastFacts 10.3: Calibration of REM probe microphone 0611 RM500SL User’s Guide Version 2.8 10.2: REM calibration facts Page 51...
9) To stop the measurement, highlight and <PICK> [Stop test]. The probe module should be replaced if it fails this test. FastFacts 10.4: Calibration check for probe module 0611 RM500SL User’s Guide Version 2.8 microphone. As part of a regular Page 52...
This Max TM SPL setting will be in effect until you change it. If the limit is exceeded during a real-ear test, the RM500SL will terminate the test and display the message “MAX TM SPL EXCEEDED”. You must then decide to either adjust the maximum output limiting of the hearing instrument or increase the Max TM SPL setting following the steps above.
Use an otoscope to verify that the tube is 2 to 5 mm from the eardrum. FastFacts 10.8: Positioning the probe tube 0611 RM500SL User’s Guide Version 2.8 Page 54...
FastFacts 11.1: REM screen setup 11.2 REM right or left ear display The RM500SL can retain and display REM test results for two ears. To switch between left and right test results, press the <Left/Right> key. FastFacts 11.2: REM right or left ear display 11.3 Graph, table or 2cc target format...
In Insertion gain, the HL scale presents aided results as improved sound-field thresholds while the speech region remains fixed. Speechmap tests view the hearing aid as increasing the ear canal SPL. Speech gets louder but the threshold remains fixed. On the HL scale in Speechmap, normal ear canal threshold becomes the 0 dB HL line and all data is replotted using this reference.
FastFacts 12.2: Manual control measurements 12.3 Sound level meter using REM probe The manual control feature enables the RM500SL to be used as a sound level meter to perform C-weighted, A-weighted or 1/12 measured by the probe and reference microphones. A and C-weighted measurements are limited to frequencies above 100 Hz and the averaging time and update rate are 384 ms.
8) Highlight and <PICK> [Type of loss] to toggle between [Sensorineural] and [Conductive] hearing loss simulations. 9) Highlight and <PICK> [Cancel] to stop the simulation. FastFacts 13.2: Sensory loss simulator operation 0611 RM500SL User’s Guide Version 2.8 16.4: Audiometric for more details. Page 58...
7) Increase venting and repeat the test until a green bar is obtained. FastFacts 14.1: Occlusion effect measurement 0611 RM500SL User’s Guide Version 2.8 to prepare the system for use and Page 59...
Values are from DSL 5.0 but differ from DSL in that values for 119 months have been used for ages >119 months. FastFacts 15.2: RECD facts 0611 RM500SL User’s Guide Version 2.8 for audiometry OR if you verify using for audiometry AND you and need not be measured.
If you have accessed RECD from the REM tests list, you may highlight and <PICK> the Age box to change the age for this reference curve. FastFacts 15.3: RECD coupler response 0611 RM500SL User’s Guide Version 2.8 2.3: Microphone connection, microphone. Connect the optional RECD transducer 7.9:...
If you have accessed RECD from the REM tests list, you may highlight and <PICK> the Age box to change the age for this reference curve. FastFacts 15.4: RECD real-ear response 0611 RM500SL User’s Guide Version 2.8 10.3: Calibration of REM probe Page 62...
A negative RECD above about 3 kHz may indicate the foam tip is blocking the probe tube. See 15.2: RECD facts, 15.3: RECD coupler response, 15.4: RECD real-ear response. FastFacts 15.5: RECD results 0611 RM500SL User’s Guide Version 2.8 Page 63...
REAG - REUG). It inherently assumes a sound-field audiogram. For non-linear hearing aids, REIG is stimulus-dependent and the dependency is specific to each hearing aid. Insertion gain fitting methods ignore these facts. Speechmap is recommended for fitting all non-linear hearing instruments.
(i.e. REIG doesn’t depend on level). The REUR curve uses the right-hand SPL scale and is shown for reference only. FastFacts 16.3: Insertion gain in HL 0611 RM500SL User’s Guide Version 2.8 11: REM Screen Setup Page 65...
16.4 Audiometric data entry Threshold data and parameters may be entered by scanning a barcode on a previous RM500SL or Verifit printout or manually using a mouse, the keypad or the numeric keypad on an external keyboard. See scanner, and 3.2: Input device operation.
For small children the peak may shift to the right and become sharper. Drainage tubes and perforated ear drums will cause large differences - usually around 1 kHz. FastFacts 16.5: REUR measurement procedure 0611 RM500SL User’s Guide Version 2.8 16.4: Audiometric data entry. 11: REM Screen Setup, 16.4:...
The REIGs will be similar except at levels which cause non-linear operation of the hearing instrument. FastFacts 16.6: REAR measurement procedure 0611 RM500SL User’s Guide Version 2.8 11: REM Screen entry, enter threshold data. 16.3: Insertion gain in HL...
16.7 SII calculation in Insertion gain The RM500SL calculates a Speech Intelligibility Index (SII) value (in %) for unaided speech at 70 dB SPL (REUR), the target REIG and for each aided test. The calculations use the 1/3 octave band method of ANSI S3.5 –1997 without the 160 Hz band and without masking effects.
SPL in the ear canal. The fitting goal is to make amplified speech audible and comfortable while avoiding discomfort for loud sounds. Originally speech was simulated using amplitude-modulated tonal signals. The RM500SL replaces these simulated speech signals with real speech, both recorded and live.
Comfort (ULC) in referring to the ear canal SPL that should never be exceeded. 5) Broadband output limiting targets are not provided. FastFacts 17.3: DSL 5.0 in Speechmap 0611 RM500SL User’s Guide Version 2.8 This has resulted in changes to These changes will be more significant when the www.audioscan.com for details of the changes.
An insertion gain version is available by selecting [Insertion gain] from the REM tests menu. The pink noise stimulus should be used. FastFacts 17.5: NAL-NL1 in Speechmap 0611 RM500SL User’s Guide Version 2.8 from those in previous 17.10: SII calculation in Speechmap Page 72...
<PICK> [Stimulus] to select the stimulus type. Highlight and <PICK> [Level] to select stimulus level. Press <Continue> to run the test and display the data. See, FastFacts 17.6: Using Speechmap 0611 RM500SL User’s Guide Version 2.8 19: Speechmap Technical 10: Real-Ear Measurement mode. 11: REM Screen Setup, and 18.2: Assessment data...
Highlight and <PICK> [Mode] to toggle between REM and S-REM. Note that REM mode should be used for vented or open fittings. Vent effects depend on the vent, the ear and the hearing aid settings. FastFacts 17.9: REM or S-REM mode 0611 RM500SL User’s Guide Version 2.8...
17.10 SII calculation in Speechmap The RM500SL calculates a Speech Intelligibility Index (SII) value (in %) for unaided speech at 70 dB SPL and for each aided test. The calculations use the 1/3 octave band method of ANSI S3.5 –1997 without the 160 Hz band and without masking effects.
18.2 Assessment data entry Threshold data and parameters may be entered by scanning a barcode on a previous RM500SL or Verifit printout or manually using a mouse, the keypad or the numeric keypad on an external keyboard. See scanner, and 3.2: Input device operation.
Continued in: 18.4: Assessment data choices - 2 FastFacts 18.3: Assessment data choices - 1 0611 RM500SL User’s Guide Version 2.8 See 4.4: Saving test setup. 18.4: Assessment data choices - 10.6: ABR...
ABR (eHL) should be selected and no conversion factors will be applied. See setup 18.3: Assessment data choices - FastFacts 18.4: Assessment data choices - 2 0611 RM500SL User’s Guide Version 2.8 10.6: ABR nHL to eHL Page 79...
LTASS) falls within the target range, especially between 500 - 4000 Hz. Press <Continue> to run the complete passage. Repeat as necessary. FastFacts 18.5: Fitting to targets for soft speech 0611 RM500SL User’s Guide Version 2.8 mode, 17.6: Using Speechmap 18.2: Assessment...
<Continue> to run and record a single sweep. Adjust the gain and output for loud sounds as for S-REM, factoring in client response. Repeat as necessary. FastFacts 18.6: Fitting to targets for loud sounds 0611 RM500SL User’s Guide Version 2.8 10.5: Max TM SPL setup). Press Page 81...
18.7: Fitting to targets for mid-level speech. FastFacts 18.8: Open fittings in Speechmap 0611 RM500SL User’s Guide Version 2.8 10: Real-Ear ®, 18: Speechmap Fitting Procedures. 18.5: Fitting to targets...
They assume familiarity with the use of Speechmap in fitting hearing aids. 1) Set up the hearing aid or receiver/earpiece as if to fit a hearing aid in REM or S- REM mode. Set it for environmental microphone (EM) only operation. Set Instrument to [BTE] or [Body] to indicate the location of the EM.
This section covers the following topics: 19.2: Speechmap stimuli 19.3: Stimulus levels For additional information see RM500SL Test Signals and Analysis FastFacts 19.1: Speechmap technical details 19.2 Speechmap stimuli The Speechmap fitting environment provides a number of well-controlled, distinctly different stimuli. These include three varieties of speech - standard (previously “shaped”), female, child, ICRA noise (digitally distorted speech) and pink noise at...
LTASS for standard speech is from Cox & Moore (1988). Loud spectrum is from ANSI S3.5-1997. Own voice spectrum is from Cornelisse et al (1991) adjusted to a 1 m reference. FastFacts 19.3: Stimulus levels 0611 RM500SL User’s Guide Version 2.8 Add to band SPL for ICRA Pink Loud...
Historically, time periods of 120, 125 or 128 ms have been used. The RM500SL uses a 128 ms time period, resulting in 100 levels (or samples) in each 1/3 octave band for a 12.8 second passage.
20 Troubleshooting 20.1 Section overview This section covers common problems encountered when using the RM500SL. If you require further assistance, note your model and serial number (located on the recessed panel) and contact your local distributor, or Audioscan at 519-268-3313 800-265-2093 (USA only), 519-268-3256 (fax) or service@audioscan.com...
Computers, fans and air conditioners may be the source of the vibration. Try turning off suspected sources to identify the cause. Relocate the source or the RM500SL or mount it on a foam pad. FastFacts 20.3: HIT high distortion or noise 20.4 HIT curves inconsistent...
No HIT reference mic. detected! This message may be displayed when starting a hearing instrument test. It indicates that the RM500SL is not measuring any sound at the HIT reference microphone. The HIT reference microphone is the white microphone located in the test chamber.
SPL. The result should have the shape of a normal REM calibration curve. If it does not, the REM microphone is defective and must be replaced. FastFacts 20.10: Invalid REM calibration 0611 RM500SL User’s Guide Version 2.8 Invalid HIT Calibration! 20.7: No HIT reference mic. detected.
It warns of a situation that could cause significant measurement errors. v Move the RM500SL and client away from walls and hard objects. Avoid placing the RM500SL under an overhanging shelf or cabinet.
Harmonic distortion accuracy... ±1% Battery drain range ...0 - 20mA Battery drain accuracy... ±5% Battery drain resolution..±01 mA 0611 RM500SL User’s Guide Version 2.8 ANSI S3.22 - 1996 and 2003 tests available aOSPL90 aFull-on Gain aReference Test Gain aFrequency Response...
SPL. Used to characterize steady state AGC action; can be a function of input level, duration and frequency. CROS, Contralateral Routing Of Signals; a type of hearing aid in which the microphone is at the ear opposite to the one receiving the amplified sound.
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Loop System, an assistive listening device that uses magnetic induction to carry a signal from a microphone/amplifier to a wire loop. The signal is picked up from the loop by a hearing aid set to the telecoil position or by a receiver with built-in telecoil, volume control, and earpiece. Loops are either worn around an individual's neck or can encircle a room, such as a classroom, providing an excellent signal-to- noise ratio.
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(ANSI S3.46). REAR, Real-Ear Aided Response, the SPL (or BSPL) as a function of frequency, at a specified measurement point in the ear canal for a specified sound field, with the hearing aid in place and turned on (ANSI S3.46).
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(rms sound pressure / 20uPa). SPLITS, coupler SPL for an inductive telephone simulator, SPL developed in a 2cc coupler by a hearing aid with the gain control at the RTS when the input is the magnetic field generated by a TMFS (ANSI S3.22).
Bentler, R.A. & Pavlovic, C.V. (1989). Transfer functions and correction factors used in hearing aid evaluation and research. Ear and Hearing, 10(10),58-63. Byrne, D. (1977). The speech spectrum - Some aspects of its significance for hearing aid selection and evaluation. British Journal of Audiology, 11,40-46.
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Cox, R.M. & Moore, J.N. (1988). Composite speech spectrum for hearing aid gain prescriptions. Journal of Speech and Hearing Research, 31:102-107. Dunn, H. K., & White, D. S. (1940). Statistical measurements on conversational speech. Journal of the Acoustical Society of America, 11:278-288.
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Pumford, J. (2005). The Desired Sensation Level Multistage Input/Output Algorithm. Trends in Amplification, 9-4, 159-197. Seewald, R.C. (1994a). Current issues in hearing aid fitting. In J-P Gagne and N. Tye-Murray (Eds.), Research in Audiological Rehabilitation: Current Trends and Future Directions. Journal of the Academy of Rehabilitative Audiology Monograph, XXVII.
24 Appendix 1: AudioNote 2.1 VERIFIT and RM500SL Test Signals and Analysis For additional details of the signals and their analysis, see the appended AudioNote. Within the European Community: EU Authorised representative: PC Werth Ltd. Audiology House 45 Nightingale Lane, London SW12 8SP UK Council Directive 93/42/EEC for Medical Devices.
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VERIFIT and RM500SL Test Signals and Analysis Introduction The Verifit and RM500SL are full-duplex dual-channel audio measurement systems designed for the testing and fitting of all types of hearing instruments and many assistive listening devices. They provide an acoustic test chamber for the testing of...
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microphone. Broad-band signals 2.2.1 Pink Noise signal The pink noise signal is available for Multicurve 2 cm and for Insertion gain and Speechmap real-ear measurements. It is a pseudo-random signal composed of 1024 simultaneous tones summed to provide a crest factor of 12 dB. The spectrum of the pink noise signal is controlled by the reference microphone in conjunction with a digital feedback loop with a frequency resolution of 1/12 octave and a response time of about 1/3 of a second.
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The test systems provide a simulated real-ear mode (S-REM) in which measurements made in the 2 cc coupler in the test chamber are converted to estimated real ear SPL. In this mode, the effects of hearing aid microphone location need to be included in the test signals so spectra are further altered to include the microphone location effects shown in Figure 3.
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All band levels are calculated with an averaging time of 128 ms. For a linear hearing aid, a pink noise stimulus will result in a response curve that has the same shape as one obtained using a swept pure tone. However, it must be remembered that, while a swept tone has the same band SPL as overall SPL, the band SPL for a noise signal is significantly lower than the overall SPL.
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These levels are determined by calculating a spectrum for each of a series of short time periods within the passage. Historically, time periods of 120, 125 or 128 ms have been used. The Verifit and RM500SL use a 128 ms time period, resulting in 100 levels (or samples) in each 1/3 octave band for a 12.8 second passage.
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2 - 3 seconds worth of data and is displayed in real time so that the effects of adjustments to hearing aid parameters are easily viewed. Pressing the Continue key causes the passage to restart and run in its entirety. The envelope and average are calculated over the full passage to provide stable and repeatable data.
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Figure 10: The highest SII is obtained when the entire speech envelope is above threshold Long-Term Average 1/3 Octave Spectra (LTASS) for Speech Signals @ Average Effort re overall SPL for entire passage; Hanning window; 128 ms average 0.00 -5.00 -10.00 -15.00 -20.00...
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1st Percentile of 1/3 Octave Band SPLs for Speech Signals @ Average Effort] re LTASS for entire passage; Hanning window; 128 ms average 14.00 12.00 10.00 8.00 6.00 4.00 1% LEVEL re LTASS - STANDARD 2.00 1% LEVEL re LTASS - FEMALE 1% LEVEL re LTASS - CHILD 1% LEVEL re LTASS - ICRA 0.00...