User Manual
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GSI AUDIOSTAR PRO
™
USER MANUAL
Part Number 2012-0100 Rev. A
Setting The Clinical Standard
www.grason-stadler.com
Grason-Stadler, 7625 Golden Triangle Drive, Suite F, Eden Prairie MN 55344 800-700-2282 • 952-278-4402 • fax 952-278-4401 • e-mail [email protected]
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GSI AudioStar Pro Clinical Audiometer Title: GSI AudioStar Pro™ Clinical Audiometer User Manual Copyright © 2012 Grason-Stadler. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means without the prior written permission of Grason-Stadler. The information in this publication is proprietary to Grason-Stadler. Compliance The CE 0344 mark identifies compliance with the Medical Device Directive 93/42/EEC. GrasonStadler is an ISO 13485 certified corporation.
European Authority Representative Grason-Stadler Kongebakken 9 2765 Smørum Denmark
0344
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Table of Contents Intended Use... 8 Warranty ... 8 Audiometric Standards ... 9 Warnings, Cautions, and Errors... 10 Status/Error Messages... 11 Customer Responsibility ... 11 Safety Precautions ... 13 Cautions - General ... 14 Warning - Connecting Additional Equipment ... 14 Warning - Electric Shock Hazards... 14 Warning - Electric Grounding ... 14 Warning - Explosion ... 14 Warning - Line Voltage Brownout and Interruptions ... 15 Warning - Connections ... 15 Warning - Battery Safety ... 15 Warning - General ... 15 Shutdown Procedure ... 15 Recycling / Disposal ... 15 Regulatory Symbols ... 16 Specifications ... 18 Audiometric Symbols ... 20 Hearing Level and Frequency Limits - Hearing Level (dB HL) ... 20 Frequency Limits ... 21 Elimination of Ambient Noise ... 22 Accessories ... 26 Country Kits ... 27 Chapter 1: Introduction ... 28 Chapter 2: Installation ... 29 External Inspection ... 29 Unpacking... 29 Connectors, Controls and Indicators ... 30 Rear Panel... 30 Right Side Panel ... 31 Left Side Panel... 32
GSI AudioStar Pro Clinical Audiometer Monitor ... 32 Bottom Panel Label... 33 Front Panel Controls... 34 Power ... 34 Stimulus Intensity Level(s) ... 34 Talk Forward ... 35 Left & Right VRA ... 35 Interlock ... 35 Tracking ... 35 Status / Audiogram Button ... 35 Data Transfer ... 35 Printing ... 36 Stimulus Channel 1 and Channel 2... 36 Transducer Output Selector ... 37 Routing Output Selector ... 38 Attenuators (HL Controls) ... 38 Tone Bar / Interrupt ... 38 Frequency Up / Down ... 38 Data Store... 38 Navigation Controls ... 39 Scorer / Timer ... 39 Aux Intercom ... 39 Monitoring ... 39 Test Type Buttons ... 40 Function Buttons... 40 Chapter 3: Function Specific Display ... 41 Navigation Menu ... 41 Tone Test Type Display... 42 High Hz Test Type Display ... 46 Speech Test Type Display ... 47 Blue Navigation Menu ... 48 Speech Status Screen... 49 Chapter 4: Operation ... 51 Preliminary Checks... 51 Typical Evaluations ... 52 Test Type Buttons ... 52 More Test Type button ... 53
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Chapter 5: Test Procedures ... 54 Routine Test Procedures ... 54 Patient Instructions ... 54 Patient Familiarization ... 54 Threshold Determination (Pure Tone): Modified Hughson-Westlake ... 54 Spondaic Speech Testing, Speech Reception Threshold (SRT) ... 55 Speech Discrimination (PB Words) ... 55 Special Test Procedures... 56 More Test Type button ... 56 Alternate Binaural Loudness Balance (ABLB) or Fowler Test ... 56 QuickSIN ... 57 SISI (Short Increment Sensitivity Index) Test ... 58 TEN Test... 58 Tone Decay Test ... 59 Additional Special Tests ... 60 Chapter 6: Configuration Application Software ... 61 Instrument ... 62 Word Lists Tab ... 62 Audiometry ... 62 Pure tone Tab ... 62 High Hz Tab ... 62 Speech Tab ... 63 Norm Values Tab ... 63 Chapter 7: Integration ... 64 GSI Instrument Services ... 64 Description... 64 Operation ... 64 Public Interface (Direct) ... 64 Data Port (Direct) ... 64 GSI Suite ... 64 NOAH 4... 65 NOAH 3... 65 AudBase ... 65 Chapter 8: Routine Maintenance ... 66 Biological Calibration Check ... 66 Periodic Checks ... 66 Earphone and Bone Vibrator Cords ... 66
GSI AudioStar Pro Clinical Audiometer Hum and Noise... 66 Distortion and Frequency Shift ... 66 Speech Level Check ... 67 Internal Controls Check ... 67 Bone Vibrator Check ... 67 Masking Level Check ... 67 Talk Forward Check ... 67 Cleaning the System ... 67 Cleaning and Disinfecting Agents ... 68 Calibration Reference Levels ... 69 Appendix 1: QuickSIN™ User Manual ... 73 Quick Start ... 73 Purpose of the QuickSIN ... 73 QuickSIN Methodology ... 74 Included with QuickSIN ... 74 How to Use the QuickSIN ... 75 Practice Lists... 76 What is SNR Loss? ... 77 Scoring... 77 Where Does the Number 25.5 Come From? ... 78 The Formula for SNR Loss... 78 Guilt-Free QuickSIN Test: for Ski-Slope Loss ... 78 Separated Speech and Noise Channels ... 79 Directional Comparison ... 79 Test Development ... 81 QuickSIN Search for Sentence Equivalence ... 83 Reliability (Statistics Made Useful) ... 85 Appendix A ... 87 Appendix B... 87 References ... 88 Appendix 2: EMC Compatibility ... 89 Electromagnetic Compatibility ... 89 Electrical Safety, EMC and Associated Standards... 89 Guidance and Manufacturer’s Declaration - Electromagnetic Emissions ... 90 Recommended Separation Distances between Portable and Mobile RF Communications Equipment and the GSI AudioStar Pro ... 90 Guidance and Manufacturer’s Declaration - Electromagnetic Immunity ... 91
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Guidance and Manufacturer’s Declaration - Electromagnetic Immunity ... 92 Appendix 3: Reference Materials... 93
GSI AudioStar Pro Clinical Audiometer
Intended Use The AudioStar Pro is intended to be used for the identification and etiology of hearing loss in patients of any age. It is intended to be used by an audiologist, ENT, hearing healthcare professional, or trained technician in a hospital, clinic, healthcare facility or other suitable quiet environment as defined in ANSI S3.1 or equivalent. Description This instrument is a two-channel clinical audiometer. This instrument has advanced functionality that makes it ideal for testing in every clinical setting, including Ear, Nose and Throat (ENT) physicians’ offices, hospitals, clinics and audiology private practices. The tests are administered via headphones – supraaural, insert phones or circum-aural headphones – or through a bone vibrator or sound field speakers. User defined test protocols allow for basic audiometric testing as well as detailed evaluations to assist in diagnosis of audiologic pathologies. Careful handling of instrument transducers and testing performed by a properly trained instrument operator should be of high priority. The patient is to remain relaxed and still while testing is being performed for optimal accuracy.
Warranty We, Grason-Stadler, warrant that this product is free from defects in material and workmanship and, when properly installed and used, will perform in accordance with applicable specifications. If within one year after original shipment, it is found not to meet this standard; it will be repaired, or at our option, replaced at no charge except for transportation costs, when returned to an authorized GrasonStadler facility. If field service is requested, there will be no charge for labor or material; however, there will be a charge for travel expense at the service center’s current rate. NOTE: Changes in the product not approved in writing by Grason-Stadler shall void this warranty. Grason-Stadler shall not be responsible for any indirect, special or consequential damages, even if notice has been given in advance of the possibility of such damages. THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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Audiometric Standards The AudioStar Pro is designed to meet or exceed the following standards: Audiometer Standard Requirements - Type 1 1. ANSI S3.6 (2010) Specification for Audiometers (Type 1) 2. IEC 60645-1 Electroacoustics - Audiological Equipment - Pure-Tone Audiometers Type 1 3. IEC 60645-2 Electroacoustics - Audiological Equipment - Equipment for Speech Audiometry 4. IEC 60645-4 Electroacoustics - Audiological Equipment - Equipment for Extended High-Frequency Audiometry 5. ISO 389-1 Reference Equivalent Threshold SPLS for Pure Tones and Supra-Aural Earphones 6. ISO 389-2 Reference Equivalent Threshold SPLS for Pure Tones and Insert Earphones 7. ISO 389-3 Reference Equivalent Threshold Force Levels for Pure Tones and Bone Vibrator 8. ISO 389-4 Reference Levels for Narrow-Band Masking Noise 9. ISO 389-5 Reference Equivalent Threshold SPLS for Pure Tones in the Frequency Range 8 kHz to 16 kHz 10. ISO 389-7 Reference zero for the calibration of audiometric equipment 11. ISO 389-8 Reference zero for the calibration of audiometric equipment
GSI AudioStar Pro Clinical Audiometer
Warnings, Cautions, and Errors The GSI AudioStar Pro Clinical Audiometer is designed to be used with a hospital grade outlet. Injury to personnel or damage to equipment can result when a three-prong to two-prong adaptor is connected between the GSI AudioStar Pro power plug and an AC outlet or extension cord. Warning!
To avoid the risk of electric shock, this equipment must only be connected to a supply mains with protective earth. Do not block access to the power switch. Audiometers which bear the Underwriters Laboratories, Inc. label should be interconnected with accessories that have the proper electrical compatibility and are listed as meeting the requirements of the UL Medical and Dental Equipment Standard. Connection of accessories not meeting these requirements may result in electrical leakage currents in excess of those allowed by the standard and present a potential electrical shock hazard to the person being tested. When testing with the High Frequency earphones, do not allow the presentation of the signal at the maximum dB HL to exceed 10 minutes. The buildup of increased temperature can cause harm to the earphones. This caution label refers the user to the accompanying literature and manuals. This icon indicates that the GSI AudioStar Pro is in compliance with Class 1, Type B requirements of IEC 60601-1.
The GSI AudioStar Pro is designed for compliance to IEC and UL 60601-1 when used in the patient vicinity. In the presence of high intensities, a yellow light will appear per channel as a warning indictor (IEC 60645-1 and ANSI S3.6). Any program aimed at obtaining reliable records of hearing thresholds should be staffed and supervised by appropriately trained individuals. Latex is not used anywhere in the manufacturing process. The base material for the earphone cushions is made from natural and synthetic rubber. Warning!
No modifications of the equipment are allowed by anyone other than a qualified GSI representative. In this manual the following two labels identify potentially dangerous or destructive conditions and procedures. The WARNING label identifies conditions or practices that may present danger to the patient and/or user.
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The CAUTION label identifies conditions or practices that could result in damage to the equipment. NOTE: Notes help identify areas of possible confusion and avoid potential problems during system operation.
Status/Error Messages Please try another selection: Indicates that an incorrect selection, such as incompatible transducers, routing, or there is no calibration data stored for the selected transducers. No test data stored: Indicates that there is no test data available to be erased or printed. Printer communication error: If communications problems occur during the course of printing, this error message will be flashed. Error: If there are general system errors, a dialog box with “Error” in the title will be shown with the given error. Record test result in comments: Test results of the ABLB and Tone Decay are not recorded directly on the report. This message indicates that the results should be discussed in the comments. The startup configuration for this test type is not fully calibrated; a search for a different configuration that is calibrated has found the currently displayed configuration: This message indicates that the selected transducers have not been calibrated. The session comments have been updated with the results of the SDT test: This message indicates that the stored speech results will appear in the comments section and will be printed directly or transferred electronically. Not supported in speech: The selected action is not supported in speech test type. Speech data limit exceeded, speech tables limited to 6 test results per ear. Latest test result will not be saved: Up to six speech tests may be stored in each ear. This message indicates that the maximum number of tests have been stored and the latest test has not been added.
Customer Responsibility Warning!
This product and its components will perform reliably only when operated and maintained in accordance with the instructions contained in this manual, accompanying labels, and/or inserts. A defective product should not be used. Make sure all connections to external accessories are snug and secured properly. Parts which may be broken or missing or are visibly worn, distorted or
GSI AudioStar Pro Clinical Audiometer contaminated should be replaced immediately with clean, genuine replacement parts manufactured by or available from GSI. This product should not be used in the presence of fluid that can come into contact with any of the electronic components or wiring. Should the user suspect fluids have contacted the system components or accessories, the unit should not be used until deemed safe by a GSI certified service technician. Do NOT use in the presence of flammable gaseous mixtures. Users should consider the possibility of explosions or fire when using this device in close proximity to flammable anesthetic gases. Do NOT use the AudioStar Pro in a highly oxygen-enriched environment, such as a hyperbaric chamber, oxygen tent, etc. Periodically, have a service technician perform electrical safety checks on the unit in order to maintain continued compliance to IEC and UL 60601-1. Equipment is not user repairable. Repairs and battery replacement must be performed by a qualified service representative only.
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Safety Precautions The following safety precautions must be observed at all times. General Safety precautions must be followed when operating electrical equipment. Failure to observe these precautions could result in damage to the equipment and injury to the operator or patient. The employer should instruct each employee in the recognition and avoidance of unsafe conditions and the regulations applicable to his or her work environment to control or eliminate any hazards or other exposure to illness or injury. It is understood that safety rules within individual organizations vary. If a conflict exists between the material contained in this manual and the rules of the organization using this instrument, the more stringent rules should take precedence. This device should only be used by hearing health care professional such as an audiologist, otolaryngologist, researcher or a technician under the direct supervision by the aforementioned specialist. Users should use their professional skills when interpreting the results and this should be done in conjunction with other testing as deemed appropriate given their professional skills. Incorrect use could lead to wrong results. The maximum sound levels (over 100 dB HL) that can be generated by the system can cause serious injury to the ear. Before attaching the earphones to the patient, ensure that: a. The system is running. b. The hearing levels in the test set to be used are appropriate. c. A biologic check of the stimulus has been performed by the operator. The customer is responsible for maintaining all system software in a safe, secure location. Do not use extension cords with this instrument or for the Isolation Box. If extension cords are used they can cause ground integrity and impedance problems. In addition to electrical safety considerations, poorly earthed mains power outlets could cause inaccurate test results due to the introduction of electrical interference from the mains. ANY EQUIPMENT CONNECTED TO THE GSI INSTRUMENT AND USED IN THE PATIENT VICINITY MUST BE POWERED BY AN ISOLATED POWER SOURCE TO MAINTAIN THE ELECTRICAL SAFETY OF THE OVERALL SYSTEM. The isolated power source can be purchased directly from GSI, or elsewhere when approved for use by GSI.
GSI AudioStar Pro Clinical Audiometer
Cautions - General If the system is not functioning properly, do not operate it until all necessary repairs are made and the unit is tested and calibrated for proper functioning in accordance with Grason-Stadler published specifications.
Warning - Connecting Additional Equipment Accessory equipment connected to the analog and digital interfaces must be certified to the respective IEC standards (IEC 950 for data processing or IEC 60601-1 for medical equipment and/or appropriate European Directives). Furthermore, all configurations shall comply with the system standard IEC 60601-1-1. Everyone who connects additional equipment to the signal input or signal output port configures a medical system standard IEC 60601-1-1. If in doubt, consult the technical service department or a local GSI representative. Connect all nonmedical equipment to the GSI Isolated Power Supply. The AC power outlets on the isolated transformer/power box are intended for use with GSI approved components only. Use of any other equipment may result in damage to the power unit. Follow all safety standards set by each place of employment. NOTE: If the instrument is connected to a PC, power to the monitor and computer must be controlled by the isolation transformer. Always leave the monitor and computer power switches in the ON position and control power from the isolation transformer. Always turn OFF system power before connecting or disconnecting system components to help guard against personal injury.
Warning - Electric Shock Hazards Do not open the case of the GSI Instrument. Do not remove any GSI instrument covers. Refer servicing to qualified personnel.
Warning - Electric Grounding This device uses a three wire power cord with a hospital grade plug (for international applications, IEC 60601-1 approved plug). The chassis is earth grounded. For grounding reliability, connect the device to a hospital grade or hospital only receptacle (for international applications, IEC 60601-1 approved receptacle). Inspect the power cord often for fraying or other damage. Do not operate the apparatus with a damaged power cord or plug. Improper grounding is a safety hazard. Periodically check the system ground integrity.
Warning - Explosion This system is not explosion proof. Do not use in the presence of flammable anesthetics or other gases.
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Warning - Line Voltage Brownout and Interruptions There are four (4) UV detectors in the digital domain, two (2) over current detectors in the analog domain, one for USB and four (4) OV/UV detectors on the main supply lines. If just ONE fails, all output to the transducers will be muted.
Warning - Connections Do not switch on any system power until all cables have been properly connected and verified. See this manual for setup instructions, which accompanies all deliveries of the system. Switch off the system power before connection disconnecting any system component(s) or accessories.
Warning - Battery Safety This instrument contains a coin-type lithium battery for a real time clock. The battery is not intended to be changed by the user. Batteries may explode or cause burns, if disassembled, crushed or exposed to fire or high temperatures. Do not short-circuit.
Warning - General Proper use of this device depends on careful reading of all instructions and labels. Follow all safety standards set by each place of employment.
Shutdown Procedure To turn off the GSI AudioStar Pro, use the power switch on the right side of the device.
Recycling / Disposal Many local laws and regulations require special procedures to recycle or dispose of electrical equipment-related waste including batteries, printed circuit boards, electronic components, wiring and other elements of electronic devices. Follow all local laws and regulations for the proper disposal of batteries and any other parts of this system. Below is the contact address for proper return or disposal of electronic wastes relating to Grason-Stadler products in Europe and other localities. The contact information for the WEEE in Europe: Grason-Stadler Kongebakken 9 2765 Smørum Denmark CRV. No. 21113379
GSI AudioStar Pro Clinical Audiometer
Regulatory Symbols No.
Symbol
IEC Pub.
Description
Conforms to European Medical Device Directive 93/94/EEC.
1
980 & 60601-1
2
980
Symbol for "USE BY."
3
980
Symbol for "BATCH CODE."
4
980 & 60601-1
5
980
6
980 & 60601-1
Return to Authorized Representative, Special disposal required.
7
980 & 60601-1
Medical Equipment Classified by Intertek Testing Services NA Inc. with respect to electric shock, fire, and mechanical hazards only, in accordance with UL 60601-1. Classified under the Medical Device Directive (93/42/EEC) as a Class IIb device.
8
980
Symbol for method of sterilization using steam or dry heat.
9
980 & 60601-1
Symbol for "CATALOG NUMBER."
10
980 & 60601-1
Symbol for “European Representative.”
11
980 & 60601-1
Symbol for “Manufacturer.”
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980 & 60601-1
Symbol for “Date of Manufacture.”
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980 & 60601-1
Attention, consult accompanying documents.
14
60601-1
15
980 & 60601-1
16
Symbol for "SERIAL NUMBER."
Symbol for "STERILE."
BF Patient Applied Part according to IEC 60601-1.
Consult Operating Instructions.
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No.
Symbol
IEC Pub.
Description
16
60601-1
On/Off - Next to power mains.
17
60601-1
Keep Dry.
18
60601-1
Transport and storage temperature range.
19
60601-1
Transport and storage humidity.
20
60601-1
This side up.
21
60601-1
Monitor.
22
60601-1
Patient response switch.
23
ISO 7010-M002
Follow Instructions for Use.
GSI AudioStar Pro Clinical Audiometer
Specifications Dimensions and Weight
Wx D x H: Height with LCD lowered: Weight: Shipping Weight:
20.1 inches x 14.6 inches x 13.2inches (LCD raised) 51.0 cm x 37.0 cm x 33.5 cm 5.5inches 14.0 cm 17 pounds 7.7 kg 27 pounds 12.25 kg
Power Consumption:
90 Watts
Channels Two independent Channels Pure Tone - Channel 1 and Channel 2 Frequency Range Air Conduction: High Frequency:* Full Frequency Range:* Bone Conduction: Sound Field:* Paired Inserts:* Frequency Accuracy: Total Harmonic Distortion:
Intensity Range ** Air Conduction (TDH): High Frequency:* Bone Conduction: Sound Field:*
Paired Inserts:*
125 Hz to 12,000*** Hz 8,000 Hz to 20,000 Hz (8 kHz, 9 kHz, 10 kHz, 11.2 kHz, 12.5 kHz, 14 kHz, 16 kHz, 18 kHz*** and 20 kHz***) 125 Hz to 20,000 Hz 250 Hz to 8,000 Hz 125 Hz to 8,000 Hz 125 Hz to 8,000 Hz ±1% < 2% (earphones and paired insert phones*) < 5% (bone vibrator)
-10 dB HL to 120 dB HL -20 dB HL to 100 dB HL (with Sennheiser HDA 200 Phones) -10 dB HL to 75 dB HL (mastoid) -10 dB HL to 65 dB HL (forehead) -10 dB HL to 90 dB HL (basic speakers) -10 dB HL to 96 dB HL (high performance speakers) -10 dB HL to 102 dB HL (high performance speakers and external booster amplifier) -10 dB HL to 120 dB HL
Masking Intensity Range (Calibrated in effective masking) Narrow Band Noise: Maximum dB HL is 15 dB below tone Signal Format Steady: Pulsed:
FM: Speech - Channel 1 and Channel 2
Microphone: INT/EXT A & INT/EXT B:
Intensity Range: Air Conduction:
Tone continuously present. Tone pulsed 200 msec ON, 200 msec OFF. Modulation Rate: 5 Hz Modulation depth +/- 5%
For live voice testing and communications Can be utilized for internal wave files or recorded speech material from an external digital device
-10 dB HL to 100 dB HL for TDH 50 (Linear Type A)
* Optional configuration ** The maximum HL values are applicable to the middle frequencies only *** RETSPL values interpolated
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Bone Conduction:
Speech - Channel 1 and Channel 2
Sound Field:* Paired Inserts:*
-10 dB HL to 55 dB HL (mastoid) -10 dB HL to 35 dB HL (forehead) -10 dB HL to 90 dB HL (basic speakers) -10 dB HL to 95 dB HL
Masking Intensity Range Speech Noise: Air Conduction -10 dB HL to 95 dB HL (TDH 50P) Bone Conduction -10 dB HL to 50 dB HL (mastoid) -10 dB HL to 35 dB HL (forehead) Sound Field: -10 dB HL to 80 dB HL White Noise: Air Conduction -10 dB HL to 95 dB HL (TDH50) Bone Conduction -10 dB HL to 50 dB HL (mastoid) -10 dB HL to 35 dB HL (forehead) Sound Field -10 dB HL to 80 dB HL Special Tests
ALT (ABLB): SISI: High Frequency:* TEN:
QuickSIN:
Special Tests (User Defined)
MLB Lombard test Pure Tone Stenger Speech Stenger SAL
Communications and Monitoring
Talk Forward:
Talk Back: Monitor:
Aux Intercom:
Environmental Requirements
Temperature: Relative Humidity: Ambient Pressure Range: Background Sound Level: Storage Temperature:
* **
Tone alternating between Channel 1 and Channel 2: Channel 1 is 400 msec ON, 400 msec OFF followed by Channel 2, 400 msec ON, 400 msecOFF. An intensity increment is added to a tone in the selected channel for 200 msec, every 5 seconds. The HL increments are in 1, 2 or 5 dB. Pure tone testing in the frequency range of 8,000 Hz to 20,000 Hz using circum-aural headphones TEN masking noise will be presented to the test ear. Pure tone stimuli between 500 and 4000 Hz may be used at 1, 2, or 5 dB increments to obtain TEN thresholds. Six (6) sentences with five (5) key words per sentence are presented in four-talker babble noise. The sentences are presented at prerecorded signal-to-noise ratios. The SNR’s used are 25, 20, 15, 10, 5, and 0.
Permits the tester to speak through the test microphone into the selected transducer at approximately the intensity level set by the front panel controls. Allows the tester to listen to comments from the patient in the testing booth. The monitor headset or monitor speaker built into the instrument housing can be used by the tester to listen to Channel 1, Channel 2, Aux intercom, and/or Talk Back signals. The built-in Auxiliary Intercom and Assistant headset allows the tester to speak directly to an Assistant without the patient hearing the conversation and allows the assistant to hear what is being presented to the patient. +15ºC to 40ºC (59 to 104ºF) 5% to 90% (non-condensing) 98 kPa to 104 kPa <35 dB(A) -20ºC to + 60ºC (-4ºF to 140ºF)
Optional configuration The maximum HL values are applicable to the middle frequencies only