Amplivox 270 User manual

D-0116365-J

INSTRUCTION FOR USE

ABOUT THIS MANUAL

1 MODEL 270 INSTRUCTION FOR USE

ABOUT THIS MANUAL

READ THIS OPERATING MANUAL BEFORE ATTEMPTING TO USE THE INSTRUMENT.

This manual is valid for the Model 270 (applies from firmware version 2T06 onwards – please refer to section 1.3).

This product is manufactured by:

Amplivox Ltd

3800 Parkside, Solihull Parkway,

Birmingham Business Park, Birmingham,

West Midlands,

B37 7YG

www.amplivox.com

For all enquiries please contact us under:

Amplivox Ltd

10393 West 70th Street

Eden Prairie

MN 55344

United States

Tel: [phone]

Fax: [phone]

[email protected]

Amplivox Ltd

3800 Parkside, Solihull Parkway,

Birmingham Business Park, Birmingham,

West Midlands,

B37 7YG

United Kingdom

Tel: [phone]

[email protected]

TABLE OF CONTENTS

2 MODEL 270 INSTRUCTION FOR USE

TABLE OF CONTENTS

ABOUT THIS MANUAL 1
TABLE OF CONTENTS 2

1. INTRODUCTION 4

1.1. THANK YOU 4

1.2. INTENDED APPLICATIONS 4

1.3. UNPACKING 4

1.4. FIRMWARE VERSION 4

1.5. STANDARD CONTENTS 4

1.6. OPTIONAL ACCESSORIES 5

2. IMPORTANT SAFETY INSTRUCTIONS 6

2.1. PRECAUTIONS 6

2.2. ELECTROMAGNETIC COMPATIBILITY (EMC) CONSIDERATIONS 6

2.3. MAINS SUPPLY OPERATION 6

2.4. AUDIOMETER CONNECTIONS 7

2.5. DATA TRANSFER TO A PRINTER 8

2.6. DATA TRANSFER TO A COMPUTER 8

2.7. LINE IN/OUT CONNECTION (AUDIO) 8

3. USING THE AUDIOMETER 9

3.1. SWITCHING THE AUDIOMETER ON AND OFF 9

3.2. OPERATING LANGUAGE 9

3.3. TESTING THE PATIENT RESPONSE SWITCH 9

3.4. AUDIOMETER DISPLAY 9

3.5. AUDIOMETER CONTROLS 9

3.5.1. Softkeys 9

3.5.2. Description of Function of Other Keys 10

3.5.3. Test menu 12

3.6. THRESHOLD RETENTION FUNCTION 12

3.7. SAVING AUDIOGRAMS IN INTERNAL MEMORY 13

3.8. LOADING AUDIOGRAMS FROM INTERNAL MEMORY 13

3.9. PRINTING AUDIOGRAMS 13

3.10. DATA TRANSFER TO NOAH OR AMPLISUITE 13

4. SUGGESTED SEQUENCE OF OPERATION AND TEST PROCEDURE 14

4.1. AUDIOMETRY PREPARATION AND AMBIENT CONDITIONS 14

4.2. TEST SYSTEM ARRANGEMENT 14

4.3. HEADSET 14

4.4. PATIENT INSTRUCTIONS 14

4.5. PRE-TEST 15

4.6. TEST 15

4.7. POST-TEST 15

5. SPECIFICATION 16

5.1. OUTPUT DATA 16

5.2. MAXIMUM HEARING LEVELS PROVIDED AT EACH FREQUENCY 17

5.3. PHYSICAL DATA 17

3 MODEL 270 INSTRUCTION FOR USE

5.4. EQUIPMENT CLASSIFICATION 17

6. SYMBOLS 19

1. TECHNICAL INFORMATION 20

7. ROUTINE MAINTENANCE 22

7.1. AUDIOMETER MAINTENANCE 22

7.2. TRANSDUCER MAINTENANCE 22

7.3. MAINS ADAPTER MAINTENANCE 23

8. INSTRUMENT STORAGE AND TRANSPORTATION 24

9. CALIBRATION AND REPAIR OF THE INSTRUMENT 24

10. GUARANTEE 24

11. ORDERING CONSUMABLES AND ACCESSORIES 25

12. DISPOSAL INFORMATION 26
APPENDIX 1 - SPEECH AUDIOMETRY 27
APPENDIX 2 - FREE FIELD CALIBRATION PROCEDURE 31
APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION 35
APPENDIX 4 - USE WITH NON-MEDICAL ELECTRICAL EQUIPMENT 41

INTRODUCTION

4 MODEL 270 INSTRUCTION FOR USE

1. INTRODUCTION

1.1. THANK YOU

Thank you for purchasing an Amplivox audiometer. The Amplivox Model 270 is a diagnostic audiometer that will give
many years of reliable service if treated with care.

1.2. INTENDED APPLICATIONS

The Model 270 diagnostic audiometer is designed for use by audiologists, general practitioners, hearing aid dispensers
and child health professionals. Capable of undertaking both air and bone conduction tests with or without masking, the
audiometer has many additional features such as the facility to support speech audiometry from live or recorded
sources, the option to select free-field equivalent output from the headphones in speech mode and a range of clinical
audiometry tests.

1.3. UNPACKING

Open the shipping carton and carefully remove all the equipment. Check against the delivery note that all the
accessories ordered have been included with your audiometer. If anything is missing, please contact Amplivox Customer
Support ([phone]; [email protected]). If you have purchased from a distributor you should contact them
directly.

Please retain the shipping carton and packing materials as the audiometer will need calibrating on an annual basis and
should be returned to Amplivox in its original shipping carton.

1.4. FIRMWARE VERSION

This operating manual is for firmware versions 2T06 onwards. To check the version of firmware on your audiometer
press the OPTIONS button followed by the TALKOVER button.

1.5. STANDARD CONTENTS

STANDARD COMPONENTS

Model 270 Audiometer

Audiometric headset

Bone vibrator headset

Patient response switch

Mains adaptor

Audiogram cards

Operating manual & ampliSuite

NOAH Audilink software

Carrying case

Calibration certificate

INTRODUCTION

5 MODEL 270 INSTRUCTION FOR USE

1.6. OPTIONAL ACCESSORIES

OPTIONAL COMPONENTS

Masking earpiece

Additional audiogram cards

Microphone and monitor headset

Insert earphones

Printer(s)

Printer cable(s)

USB Cable

Audiocups (noise reducing earphone
enclosures)

IMPORTANT SAFETY INSTRUCTIONS

6 MODEL 270 INSTRUCTION FOR USE

2. IMPORTANT SAFETY INSTRUCTIONS

The Model 270 instrument must be used only by practitioners qualified to perform audiometric tests.
It is intended for use as a screening and diagnostic tool.

2.1. PRECAUTIONS

READ THIS OPERATING MANUAL BEFORE ATTEMPTING TO USE THE INSTRUMENT

To comply with the standards IEC 60601-1 for safety and IEC 60601-1-2 for EMC the audiometer is designed to be used
only with the medically-approved mains adapter supplied, which is specified as part of the equipment. Do not use any
other type of mains adapter with this instrument. Refer to Section 12 for the stock number of the adapter.

The audiometer is for indoor use only and should be used only as described in this manual.

The transducers supplied with the audiometer are specifically calibrated with it; if these transducers are changed
calibration will be required.

Do not immerse the unit in any fluids. See Section 8 of this manual for the proper cleaning procedure for the instrument
and its accessories and the function of single-use parts.

Do not use the instrument in an oxygen-rich environment or in the presence of a flammable anaesthetic mixture or
other flammable agents.

Do not drop or otherwise impact this instrument. If the instrument is dropped or damaged, return it to the manufacturer
for repair and/or calibration. Do not use the instrument if any damage is suspected.

The instrument must be stored and used within the specified temperature, pressure and humidity ranges (see Sections
7 and 9).

Do not attempt to open, modify or service the instrument. Return the instrument to the manufacturer or distributor for
all repair and servicing requirements. Opening the instrument will void the warranty.

2.2. ELECTROMAGNETIC COMPATIBILITY (EMC) CONSIDERATIONS

Medical electrical equipment needs special precautions regarding EMC and needs to be installed and put into service
according to the EMC information in Appendix 3. This provides guidance on the electromagnetic environment in which
to operate the instrument.

Portable and mobile radio-frequency (RF) communications equipment can affect medical electrical equipment. The
instrument should not be used adjacent to or stacked with other equipment; if this is necessary the instrument should
be observed to verify normal operation.

2.3. MAINS SUPPLY OPERATION

The audiometer is designed for continuous operation and is powered by a mains adapter which is supplied, and specified
as part of the equipment. If a replacement is required, please contact your Amplivox distributor.

IMPORTANT SAFETY INSTRUCTIONS

7 MODEL 270 INSTRUCTION FOR USE

All other connections must be made before connecting the output lead from the adapter into the POWER input socket
on the back of the audiometer. Switch on the mains supply - the indicator on the adapter and the POWER indicator on
the audiometer will both illuminate green, showing that the instrument is ready for use.

The output from mains adapter is fitted with electronic circuit protection. In case of overload the adapter will shut down
and the indicator will be extinguished. When the fault is cleared the adapter will operate as normal.

The input to the mains adapter is protected with a non-replaceable fuse. If this fails the adapter will not operate.

The mains adapter is the mains disconnect device and therefore the audiometer should be positioned such that easy
access to the mains adapter is possible.

2.4. AUDIOMETER CONNECTIONS

All the relevant accessory terminals and connections are labelled to ensure correct identification and connection as
follows:

Socket Label

Socket Type

Colour Code

Connected Part

Notes

MIC 1

3.5mm jack

Speech Input Microphone *

MONITOR

3.5mm jack

Monitor Earphone *

BONE

6.3mm jack

Grey

Bone Vibrator Headset *

INSERT

3.5mm jack

Masking Earphone *

RIGHT
LEFT

6.3mm jack 6.3mm jack

Red
Blue

Air conduction headset *
MIC 2

3.5mm jack

Talkback Microphone *

POWER

2.5mm power jack

Mains AC/DC Adapter *

RESPONSE

6.3mm jack

Black

Patient Response Switch *

LINE IN
LINE OUT

3.5mm jack

3.5mm jack

CD/tape player
External amplifier

See 2.7
DATA

6 pin mini DIN

Printer *

See 2.5

USB

USB Connector

Computer (via USB port)

See 2.6

The relevant part numbers are indicated in Section 12.

For connected parts marked * only connect the accessories supplied with the instrument or supplied
by Amplivox or an Amplivox distributor. These parts have been tested for use with the Model 270
Diagnostic Audiometer for compliance with the standards IEC 60601-1 and IEC 60601-1-2. The use of
accessories other than those specified may compromise compliance with these standards. For other
sockets refer to Appendix 4.

IMPORTANT SAFETY INSTRUCTIONS

8 MODEL 270 INSTRUCTION FOR USE

2.5. DATA TRANSFER TO A PRINTER

Please refer to Appendix 4 for important information regarding the connection of non-medical
electrical equipment to medical electrical equipment

The audiometer can be upgraded with an option to allow connection to one of two designated portable thermal printers
for printing air conduction, bone conduction, speech and ULL test results (see 3.9). You must use the designated cable
for each printer, which is supplied with this option.

Upon receipt of the printer it must be initially charged for a minimum of 15 hours prior to use.

2.6. DATA TRANSFER TO A COMPUTER

Please refer to Appendix 4 for important information regarding the connection of non-medical
electrical equipment to medical electrical equipment.

The audiometer is supplied with software to allow connection to a computer for the transfer of test results (see Section

3.10). You must use the designated USB cable which is available from Amplivox (see Section 12).

2.7. LINE IN/OUT CONNECTION (AUDIO)

Please refer to Appendix 4 for important information regarding the connection of non-medical
electrical equipment to medical electrical equipment.

The Model 270 has audio line in/out connections for CD or tape player input (e.g. for recorded speech testing) and
amplifier output.

Line out connections are switched on only when FREEFIELD is selected. The following connections apply to both LINE IN
and LINE OUT.

Main Body Segment

Mid segment

End segment

Ground

Right Channel

Left Channel

For more information on live and recorded speech please see Appendix 1.

USING THE AUDIOMETER

9 MODEL 270 INSTRUCTION FOR USE

3. USING THE AUDIOMETER

3.1. SWITCHING THE AUDIOMETER ON AND OFF

Press the key marked highlighted centre right of the front panel. No warm-up time is required. The display will briefly
show the model and the type of headphone currently selected for use.

If a secondary headphone has been enabled (e.g. E-5A) it will then be necessary to select the required headphone as
follows:

• Either - press the key under OK (on the display) to confirm the current headphone selection

• Or - press the key under CHANGE to toggle to the other option and then OK to confirm the selection

Note: the headphone selection must be confirmed before any other operation can be performed. The display will then
be as shown in 3.4.

To switch off, press the key marked again and then the key under YES to confirm. To cancel switch-off press the key
under NO or QUIT

3.2. OPERATING LANGUAGE

To select the operating language for the audiometer (English or German) continue to hold when switching on. An
additional display will allow the selection of English (Softkey 1) or Deutsch (Softkey 3).

3.3. TESTING THE PATIENT RESPONSE SWITCH

Press the patient response switch and the light labelled RESPONSE (to the left of the display) will illuminate green.

3.4. AUDIOMETER DISPLAY

On start-up the display will show the following default setting:

SIGNAL MASKING

30dBHL 1kHz OFF

< > < > THL

This indicates that when the PRESENT key is pressed, a tone will be presented at 30dBHL at a frequency of 1kHz (1000Hz)
to the designated ear. No masking noise is output. On start up the audiometer defaults to the left ear.

3.5. AUDIOMETER CONTROLS

3.5.1. SOFTKEYS

Four softkeys are provided below the display that refer to an associated option shown on the display. In this operating
manual these are referenced as Softkey 1 to Softkey 4 from left to right.

USING THE AUDIOMETER

10 MODEL 270 INSTRUCTION FOR USE

3.5.2 OPTIONS key

Pressing the OPTIONS key and then using the softkeys allows the operator to step through the options (use the NEXT
softkey) and modify the settings as required. Pressing the softkey below QUIT exits the options menu and saves the
settings.

Menu Option Description

Clear test?: Clears all displayed test results if the YES key is pressed; stored test results are not affected

Save audiogram to 1: Use the UP key to select the intended storage location and press the SAVE key

Load audiogram no. 1: Use the UP key to select the required storage location and press the LOAD key

Contrast: Adjust using the UP and DOWN keys

Bone masking: Selects the headset or the optional insert masking earpiece as the means of masking; select

‘Insert’ or ‘Phones’ key

Select phones: This option is only available if a secondary headphone is enabled; use Softkeys 1 or 2 to select

the required headphone type

FF equiv speech?: This option is only available if either DD45 or TDH39 is the selected headphone; if activated,

free-field equivalent levels will output to the headphone in speech mode (see Appendix 1)

Store on 2 of 3?: Automatically stores a threshold if the responses made to two out of three test signals are at

the same hearing level

Set freefield levels?: This option provides access to the freefield calibration function; refer to Appendix 2 for

details

External talkover?: Select NO to use the internal microphone and YES to use the MIC 1 input

Display Counter?: Activates a percentage counter for use with speech testing (refer to Appendix 1)

Select printer: Use the appropriate softkey to select either the Able (AP1300) or the Martel (MCP8830)

printer or the Sanibel (MPT-II) printer.

Please note: In order to use the Sanibel printer, select ABLE printer in the settings. After
confirming the ABLE printer, the 270 will connect to the Sanibel printer, too.

Omit 750/1k5/3k/6k?: To exclude these frequencies from those available for testing press the YES key

Present Time: Select the minimum and maximum times that a stimulus can sound when the PRESENT key

is pressed; either 0.5sec (min) & 10sec (max), or 1.0 sec (min) & 2.0 sec (max)

FF Speech units: The units displayed for freefield speech may be switched between dBHL and dBSPL

3.5.2. DESCRIPTION OF FUNCTION OF OTHER KEYS

SIGNAL HL The rotary control is used to increase or decrease the signal level in the selected step size.

MASK HL The rotary control is used to increase or decrease the masking level in the selected step size. (The MASK

key must be selected – see below)

SINE Selects a pure tone as the test signal; the indicator above the key illuminates green

USING THE AUDIOMETER

11 MODEL 270 INSTRUCTION FOR USE

WARBLE Selects a frequency modulated tone as the test signal; the indicator above the key illuminates green

SPEECH Selects speech mode; the indicator above the key illuminates green; refer to Appendix 1 for details

(note that initially, only Softkeys 1 & 3 have a function)

MASK Switches on masking at 30dBHL - narrow band (for pure tones) or speech-weighted masking; the

indicators above the key and to the right of the display illuminate green; for speech mode use Softkey
4 to select INT for internally generated noise or EXT (with Softkey 1 used to select LINE) to route
recorded noise via the LINE IN connection

LEFT Press once to select the left ear; the indicator above the key illuminates green

RIGHT Press once to select the left ear; the indicator above the key illuminates green

PULSE Enables pulse tone present function; the indicator above the key illuminates green

REVERSE Presents the signal continuously; the indicator above the key illuminates green. Pressing the PRESENT

key interrupts the signal

+20dB This enables tone levels to be presented with up to 20dB higher output; press the key and then use the

SIGNAL rotary control to access the extra 20dB; a green indicator above the key is used to show that
the function is active, and an additional display message indicates levels greater than 100dBHL. Note:

this function will not operate if continuous tone presentation has been enabled.

LOCK Synchronous masking function. Locks signal and mask output at a constant difference when the SIGNAL

control is adjusted. An indicator above the key illuminates green when active. The MASK control adjusts
masking independently.

AIR Outputs the signal to the earphones; the indicator above the key illuminates green

BONE Outputs the signal to the bone vibrator; the indicator above the key illuminates green

FREEFIELD Routes signals to LINE output socket; the indicator above the key illuminates green

Hz Press the  key to select a lower frequency and the  key to select a higher frequency

PRESENT Press to present the displayed test signal to the patient. The “PRESENT” indicator to the left of the

display will be illuminated green during tone presentation.

TALKOVER Interrupts test and routes operator’s voice from the internal microphone (or MIC 1 input) to headset.

The attenuation level can be adjusted with the SIGNAL rotary control.

TALKBACK While selected (as indicated by the indicator above the key) the signal from MIC2 is routed continuously

to the MONITOR output. Press the key again to de-select. The talkback level may be adjusted by the
SIGNAL rotary control while key is held down.

PRINT Press to print audiogram; see Section 3.9 for further details

dB STEP Enables the operator to set either 2.5dB or 5dB as the default step size.

PHONES This option is only available if a secondary headphone has been enabled; this will enable the operator

to select the required output transducers.

STORE Saves the displayed combination of frequency, attenuation and ear as a threshold retention value.

Please see Section 3.6 for further details.

USING THE AUDIOMETER

12 MODEL 270 INSTRUCTION FOR USE

3.5.3. TEST MENU

This key enables the selection of the following standard tests. Exit each test by pressing the TEST MENU key again.

Menu Option Description

STENG. Stenger: Routes tone or speech to both earphones

simultaneously. Use the SIGNAL rotary control to adjust the Left channel level and the MASK rotary

control to adjust the right. Refer to Appendix 1 for details of the Stenger test in speech mode.

ABLB Alternate Binaural Loudness Balance: Routes tone to each earphone alternately. Use the SIGNAL rotary

control to adjust the Left channel level and the MASK rotary control to adjust the right. Pressing the
PRESENT key interrupts the signal presented.

SISI Short Increment Sensitivity Index: Presents a tone continuously at the level and frequency displayed.

Pressing the PRESENT key increases the level by the increment shown on the lower line of the display.
Change this increment by using the UP & DOWN softkeys. Softkey 4 switches between the initial display
and a counter that logs and displays the results of the test as a percentage:

• Use Softkey 1 to record a response

• Use Softkey 2 to record no response

• Use Softkey 3 to clear the results display

• Use Softkey 4 to return to the initial SISI display

3.6. THRESHOLD RETENTION FUNCTION

This function records the thresholds for both ears at each frequency tested (air conduction, bone conduction and ULL).

Once a threshold has been determined press the STORE key. Alternatively use the “Store on 2 of 3” function (see Section

3.5.2). The threshold will be recorded and displayed as shown below.

The operator can then review the results at the end of the test and record them on an audiogram card, print them with
the optional printer (see Section 3.9), save them to the internal memory (see Section 3.7) and/or transfer the results to
a computer (see Section 3.10).

To review the retained thresholds, select the required frequency using the  Hz  keys. The recorded values for the
left and right ears are shown on the lower line of the display, designated L and R respectively.

SIGNAL MASKING

10dBHL 4kHz OFF
[ 20L] [ 10R] THL

This display shows
thresholds at 4kHz

THRESHOLDS

Left ear 20dBHL

Right ear 10dBHL

To clear the Threshold Retention memory, use the Clear Test menu option described in Section 3.5.2.

Bone Conduction and Uncomfortable Loudness Levels (ULL)

To record and review bone conduction thresholds use the BONE key.

USING THE AUDIOMETER

13 MODEL 270 INSTRUCTION FOR USE

To record uncomfortable loudness levels (ULL) press Softkey 4 with Air conduction selected. The display will be similar
to that shown below, and ULL thresholds are recorded and reviewed as described above.

SIGNAL MASKING

40dBHL 1kHz OFF

[ 45L] [ 40R] ULL

3.7. SAVING AUDIOGRAMS IN INTERNAL MEMORY

The user may store up to 12 audiograms, referenced by number, in the internal memory of the audiometer. To save the
current set of audiogram thresholds press the OPTIONS key, press the NEXT key repeatedly until “Save Audiogram to ”
appears on screen. Use the UP key to select a location numbered 1-12 and then press the SAVE key. Any results for ULL
thresholds or speech testing (see Appendix 1) will also be saved.

Note that the Save process will overwrite any records that exist in the memory location. Press the QUIT key once
confirmation that the thresholds have been saved appears on the screen.

3.8. LOADING AUDIOGRAMS FROM INTERNAL MEMORY

Press the OPTIONS key and then press NEXT repeatedly until “Load Audiogram no ” appears on screen. Select the
required audiogram (1-12), using the UP key and then press the LOAD key. Press the QUIT key once confirmation that
the thresholds have been retrieved appears on screen.

3.9. PRINTING AUDIOGRAMS

Three designated thermal printers (the Able AP1300 or the Martel MCP8830 or the Sanibel MP-II) are available as
options for use with the Model 270 audiometer. The correct printer must be selected (use the MENU options described
in Section 3.5.2 to make this selection).

• Connect the audiometer to the printer with supplied printer cable (refer to Section 2.5 of this operating manual

for printer set-up). Insert the 6-pin mini DIN into the DATA socket on the back of the audiometer. Insert the
terminal plug into the socket at the back of the printer. Note that the printer cables for the Able printer (stock
number A105) and Martel printer (stock number A104) and the Sanibel Printer (A101) are not compatible.

• Ensure the printer is switched on and ready to print.

• Load the desired audiogram as described in 3.8; to print the current audiogram ignore this instruction

• Press the PRINT key. On the prompt “Is printer ready?” press the YES key. The audiogram will then print.

3.10. DATA TRANSFER TO NOAH OR AMPLISUITE

To transfer test results stored within the audiometer to a NOAH database the Amplivox NOAH Audilink software must be
installed on to a computer. Alternatively, Amplivox ampliSuite allows data to be transferred to a and subsequently viewed,
annotated & printed. This software is supplied on a CD which includes this operating manual.

Refer to the installation & operating instructions provided with NOAH or ampliSuite for further details.

SUGGESTED SEQUENCE OF OPERATION AND TEST PROCEDURE

14 MODEL 270 INSTRUCTION FOR USE

4. SUGGESTED SEQUENCE OF OPERATION AND TEST

PROCEDURE

The following applies to air conduction measurements. For illustrative purposes 5dB steps are used. Refer also to ISO
8253 for guidance.

4.1. AUDIOMETRY PREPARATION AND AMBIENT CONDITIONS

Refer to the various audiometric standards and other relevant publications for guidance on audiometric testing.

Audiometric testing should always be performed in quiet conditions (e.g. a quiet room or an acoustic booth). The
optional Audiocups can provide an additional level of isolation from ambient noise. For further explanation on
permissible ambient noise levels, please refer to the audiometry standard ISO6189.

4.2. TEST SYSTEM ARRANGEMENT

The schematic diagram below shows a typical example of the use of audiometric test equipment. The audiometer is
located on the desk of a seated operator as shown.

The patient is seated in front of the desk facing away from the operator. The patient wears a headset or appropriate
transducer (see Section 4.3) and responds to test stimuli by use of a hand-held switch which is also connected to the
instrument.

4.3. HEADSET

The headset or appropriate transducer must be fitted by a qualified person to ensure a proper seal and a comfortable
fit. The leads from the headset are connected to the instrument and the headset is then fitted to the patient.

4.4. PATIENT INSTRUCTIONS

The patient should be given the following instructions using the TALKOVER function:

• “As soon as you hear the tone, press the response switch. When you no longer hear the tone release the

response switch”

Operator

Audiomete

Computer (optional)

Patient, wearing

Headset lead

Response switch & lead

SUGGESTED SEQUENCE OF OPERATION AND TEST PROCEDURE

15 MODEL 270 INSTRUCTION FOR USE

4.5. PRE-TEST

(1) Connect the required accessories and switch the audiometer on
(2) Perform a listening check
(3) Decide whether to use the Threshold Retention Function (see Section 3.6) or an audiogram card to record the

thresholds

(4) Prepare the test environment & patient (see Sections 4.1 to 4.4)
(5) Select the better hearing ear (according to the patient) by pressing either the LEFT or RIGHT key

4.6. TEST

(6) Present the first test tone at 30dB at 1kHz
(7) If the patient responds, reduce the signal level in 10dB steps until they no longer respond; then increase the signal

level in 5dB steps until the patient responds

(8) If the patient fails to hear the first tone, increase the signal level in 5dB steps until they do respond and then

continue with step 9

(9) Repeat the test by reducing the signal level in 10dB steps until the patient no longer responds; then increase the

signal level in 5dB steps until they do respond and note this level

(10) If Store on 2 of 3 is selected, go to step 12
(11) Repeat step 9 until the patient responds three out of a maximum of five times at the same signal level, indicating

the patient’s hearing threshold level for that frequency; mark the threshold on an audiogram card or press the

STORE key once to activate the Threshold Retention Function which displays the threshold on screen

(12) If Store on 2 of 3 is selected, repeat step 9 until the patient has responded 2 out of a maximum of 3 times at the

same signal level; this will automatically display the threshold on the screen

(13) Proceed to the next test frequency and repeat steps 6 to 12
(14) Repeat steps 6 to 13 for the other ear

4.7. POST-TEST

(15) Use the Threshold Retention Function to review the results (See 3.6)
(16) If required do one or more of the following:

• Record the results on an audiogram card, or

• Save the results to the internal memory (Section 3.7), or

• Print the results (Section 3.9), or

• Transfer the results to a computer (Section 3.10)

To clear the Threshold Retention memory, use the Clear test menu option described in Section 3.5.2.

SPECIFICATION

16 MODEL 270 INSTRUCTION FOR USE

5. SPECIFICATION

5.1. OUTPUT DATA

Outputs: Left earphone, Right earphone, Bone (L&R) Insert masking and Freefield

Frequency range (Hz): Air: 125-8kHz

Bone: 250Hz-8kHz

Frequency accuracy: <1%

Distortion: <2%

Output level range (AC): -10dBHL to 120dBHL maximum

Output level range (BC): -10dBHL to 70dBHL maximum

Output level range (FF): Up to 90dB

Insert masking output: 90dBHL max (250-4kHz)

Output level accuracy: Within 3dB

Output level step size: 2.5 or 5dB

Output transducer (AC): DD45 earphones (supplied)

E-5A insert earphones (option)

Output transducer (BC): B-71 bone vibrator (supplied)

Tone present: Single, pulsed, warble or continuous

Masking: Narrowband (tone) or speech-weighted

Synchronous channel: See Section 3.5.3 (LOCK)

Clinical tests: SISI, Stenger & ABLB (Fowler)

Communication: Integral talkover and talkback facility

Recorded speech: Tape or CD input

Live speech: 1 x microphone input

Monitoring indicator: VU - (to IEC 60268-17; ANSI S3.6:2004)

USB interface: Transfer of test results to a computer

SPECIFICATION

17 MODEL 270 INSTRUCTION FOR USE

5.2. MAXIMUM HEARING LEVELS PROVIDED AT EACH FREQUENCY

Frequency, Hz

Air conduction, dBHL

Bone conduction, dBHL

125

80

-

250

100

45

500

115

60

750

120

65

1000

120

70

1500

120

70

2000

120

70

3000

120

70

4000

115

70

6000

110

50

8000

100

40

5.3. PHYSICAL DATA

Display: 2 lines of 24 characters

Mains power: 100-240Vac; 50-60Hz; 0.5A

Input Rating: 5Vdc; 1.1 A

Dimensions: 355mm long x 230mm deep x 100mm high

Weight: 1.6kg

Safety: IEC 60601-1 (plus UL, CSA & EN deviations)

EMC: IEC 60601-1-2

CE mark: To the EU Medical Device Regulation

5.4. EQUIPMENT CLASSIFICATION

Type of protection against electric shock Powered via SELV ClassII mains adapter

Degree of protection against electric shock Type B applied part

Degree of protection against ingress of water Not protected

Mode of operation Continuous operation

Equipment mobility Portable

SPECIFICATION

18 MODEL 270 INSTRUCTION FOR USE

The Model 270 Audiometer is classified as a Class IIa device under Annex II of the EU Medical Devices Regulation. It is
intended for use as a diagnostic audiometer instrument.

SYMBOLS

19 MODEL 270 INSTRUCTION FOR USE

6. SYMBOLS

The following symbols appear on the audiometer or mains adapter:

Definition: Identifies the control by means of which the instrument is switched on from (or returned to)
a standby condition.

Definition: Refer to instruction manual (mandatory).

Definition: Type B applied part – an applied part providing protection against electric shock, particularly

regarding allowable patient leakage current and patient auxiliary current.

The applied parts are the left & right earphones, bone vibrator, insert masker, patient response switch and
the associated cables.

Definition: The output from the mains AC adapter is Direct Current

Definition: Class II equipment – equipment in which protection against electric shock does not rely on

basic insulation only, but in which additional safety precautions such as double insulation or reinforced
insulation are provided, there being no provision for protective earthing or reliance upon installation
conditions.

Definition: Medical device.

TECHNICAL INFORMATION

20 MODEL 270 INSTRUCTION FOR USE

7. TECHNICAL INFORMATION

Audiometer

Audiometer type: Type 2 (IEC 60645-1:2017)

Type B-E (IEC 60645-1:2017 & IEC 60645-2: 1993, Annex A)

Type 3BE (ANSI S3.6:2004)

Frequency Modulation

Carrier frequencies: 125Hz to 8kHz as per pure tones

Modulation waveform: Sinusoidal

Rising and falling symmetry: Symmetrical on linear frequency scale

Modulating frequency: 15.625Hz

Frequency deviation: +/-10%

Speech Channel

Frequency response: +/- 3dB from 100Hz to 10kHz electrical

Voltage requirement at 0dB

input level setting to zero meter: 1.20Vrms at 1kHz

Output level: 90dBSPL at 1kHz for attenuator setting of 70dBHL with level meter at 0dB

Masking Sounds

Masking sounds available: Narrow bands at test frequencies and Speech weighted noise

Narrow-band noise bandwidth: Meets IEC 60645-1; ANSI S3.6

Speech noise bandwidth: Meets IEC 60645-2; ANSI S3.6

Reference levels: Refer to ISO 389-4

Insert Masking Earpiece

Calibration method: With 2cc coupler compliant with IEC 126

TECHNICAL INFORMATION

21 MODEL 270 INSTRUCTION FOR USE

Transducers

Types and reference levels: DD45: ISO 389-1, Table 2

E-5A: ISO 389-2, Table 1

B-71: ISO 389-3, Table 1

Static headband force: Headphones: 4.5N

Bone vibrator: 5.4N

Bone vibrator calibrated: For mastoid placement & unoccluded test ear

Sound attenuation characteristics: ISO8253-1, Table 3

Airborne sound from bone vibrator: See Br. J. Audiol. 1980, P73-75

Earphone Sound Attenuation Characteristics

Frequency, Hz

125

250

500

1000

2000

4000

8000

Attenuation, dB

2 5 7

15

25

31

23

Environmental

Operating temperature: +15oC to +35oC

Operating humidity: 30% to 90% (non-condensing)

Atmospheric pressure: 700 hPa to 1060 hPa

Input / Output

Power input: 2.5mm barrel-type socket.

Mic input impedance: 2500 Ohms

Mic input connection: Mono 3.5mm Jack socket

Line input impedance: 6800 Ohms

Line in/out connections: Stereo 3.5mm Jack Sockets

Patient response input: 6.3mm Jack socket

Left / Right / Bone outputs: 6.3mm Jack socket

Monitor output: Mono 3.5mm Jack socket

Insert output: Mono 3.5mm Jack socket

USB: Type B socket

Maximum voltage at any output: 12V peak

ROUTINE MAINTENANCE

22 MODEL 270 INSTRUCTION FOR USE

8. ROUTINE MAINTENANCE

8.1. AUDIOMETER MAINTENANCE

The Model 270 audiometer is a precision instrument. Handle it carefully in order to ensure its continued accuracy and
service. When cleaning the instrument, first disconnect it from the mains supply. Use a soft cloth and mild detergent to
clean the instrument panel when required. Refer to ISO 8253-1 for additional guidance.

8.2. TRANSDUCER MAINTENANCE

Before use check the transducer cables and connectors for signs of wear and/or damage. If you find any, please replace
the item immediately by contacting Amplivox or your Amplivox distributor, requesting the relevant part number (see
Section 12).

Handle the audiometric headset, bone vibrator headset and other accessories with care. For parts that are in direct
contact with the patient it is recommended that replacement parts are used or the parts are subjected to a standard
disinfecting procedure between patients.

This includes physically cleaning and use of a recognised disinfectant. The specific manufacturer's instructions should
be followed for use of this disinfecting agent to provide an appropriated level of cleanliness.

During the cleaning process do not allow moisture to enter the earphone, insert masker, monitor
or microphone grills etc. For specific accessories refer to the sections below.

Earphones

Clean the ear cushions (including those on the Audiocups, if used) with a recognised disinfectant, e.g. a “Mediswab”.

Insert Earphone/Masker

Never insert or in any way use the insert masker without using a new, clean and fault-free test tip. This part is for single
use only - that is, each test tip is intended to be used once only for a single ear for a single patient. Do not reuse test
tips as this will pose the risk of ear-to-ear or patient-to-patient cross infection.

Insert Earphones

The disposable foam eartips supplied with the optional EarTone5A insert transducers are for single use only - that is,
each eartip is intended to be used once only for a single ear for a single patient. Do not reuse eartips as this will pose
the risk of ear-to-ear or patient-to-patient cross infection.

• Ensure that the black tubing protruding the foam eartip is not applied to the patient; this must be attached to

the sound tube of the insert transducer

• Roll the foam eartip into the smallest possible diameter

• Insert the eartip into the ear canal of the patient

• Hold the eartip until it has expanded and a seal is achieved

• After testing the patient the foam eartip including the black tubing must be detached from the sound tube

• The insert transducer should be examined prior to attaching a new foam eartip

ROUTINE MAINTENANCE

23 MODEL 270 INSTRUCTION FOR USE

8.3. MAINS ADAPTER MAINTENANCE

Before use check the mains AC adapter for signs of wear and/or damage. If you find any replace the adapter immediately
by contacting Amplivox or your Amplivox distributor. Refer to Section 12 for approved part numbers

DO NOT USE ANY OTHER TYPE OF MAINS ADAPTER WITH THIS INSTRUMENT. See Section 2.3.

INSTRUMENT STORAGE AND TRANSPORTATION

24 MODEL 270 INSTRUCTION FOR USE

9. INSTRUMENT STORAGE AND TRANSPORTATION

Please note that this instrument can be stored or transported with the following environmental parameters:

Temperature: -20oC to +70oC

Humidity: 10% to 90% (non-condensing)

Atmospheric Pressure: 500 hPa to 1060 hPa

10. CALIBRATION AND REPAIR OF THE INSTRUMENT

Amplivox recommend that this audiometer should be calibrated on an annual basis. Please contact Amplivox or the
designated distributor for details of calibration services. Refer to ISO 8253-1 for additional guidance.

The instrument should be returned to the manufacturer for service & repair. There are no user­serviceable parts within it.

When packing the instrument for shipping, please use the original shipping carton and packing materials. Please also
ensure that the headset leads are not wrapped around the headband of the headset.

11. GUARANTEE

All Amplivox instruments are guaranteed against faulty materials and manufacture. The instrument will be repaired free
of charge for a period of three years from the date of despatch if returned, carriage paid, to the Amplivox service
department. Return carriage is free of charge for customers in the UK and chargeable for overseas customers.

Important Note:

The following exceptions apply:

Earphones, bone vibrator and other transducers may go out of calibration due to rough handling or impact (dropping).
The life of the leads is also dependent upon conditions of use. These parts are only guaranteed against faulty materials
or manufacture.

ORDERING CONSUMABLES AND ACCESSORIES

25 MODEL 270 INSTRUCTION FOR USE

12. ORDERING CONSUMABLES AND ACCESSORIES

To order consumables, additional accessories and to replace detachable parts that have been damaged, please contact
Amplivox for current prices and delivery charges. The items available are listed below:

Stock No.

Description

A022

8010855

Audiocups (noise reducing earphone enclosures)

AC1042

8010835

Audiocup ear cushion

AC1047

8507381

Audiocup headband

AC1048

8010834

Audiocup headband cover

A023

8010840

Headband (standard headphone)

A026

8010857

Earphone cushion

A032

8010876

Earphones DD45 *

A030

8010822

Headset lead

A080

8506731

Bone vibrator B71 *

A025

8011098

Bone vibrator headband

A029

8011136

Bone vibrator lead

B129

8004673

Carrying case

8512734

Approved mains adapter (UES12LCP)

A085

8011155

Patient response switch

A051

8013007

Audiogram cards (pack of 50)

C15

8507921

Masking earpiece *

C13

8001127

Masking earpiece ear tip

C12

8507175

Masking earpiece ear hanger

C14

8004447

Masking earpiece lead

8101884

Insert earphones *

C17

8507435

Microphone and monitor headset

PT02

8029305

Printer Sanibel MPT-II

A102

8004419

Printer cable for audiometer to Sanibel MPT-II

C0104

8029305

Thermal Printer paper for Sanibel MPT-II

F07

8507230

USB Cable, 2.0m

A109

8507853

Free field cable (connects to LINE IN/LINE OUT)

Accessories marked * require calibration with the specific audiometer to be used. Do not attempt to
use these accessories until the audiometer has been calibrated to match their characteristics.

Shipping documentation will reference the stock number quoted above, and images of the parts alongside the relevant
stock number are available on the Amplivox website (www.amplivox.com ). The required fitting instructions are supplied
with each part.

DISPOSAL INFORMATION

26 MODEL 270 INSTRUCTION FOR USE

13. DISPOSAL INFORMATION

Amplivox Limited is fully compliant with the WEEE (Waste Electrical and Electronic Equipment) Regulations.
Our PRN (Producer Registration Number) is WEE/GA0116XU and we are registered with the approved WEEE
Compliance Scheme, B2B Compliance, approval number WEE/MP3338PT/SCH.

The main purpose of the WEEE Regulations is to encourage the segregation of waste electrical items from the general
waste stream and into reuse, recovery and recycling routes.

For any waste electrical units purchased from Amplivox that either:

• bear the crossed out wheeled bin symbol with black bar underneath

• or, have been replaced with new Amplivox products on a like-for-like basis

please contact our WEEE Compliance Scheme using the details below. B2B Compliance will be able to provide further
information on how to recycle your waste electrical units and answer any queries you may have.

B2B Compliance

Tel: [phone] (Option 2)

Email: [email protected]

APPENDIX 1 - SPEECH AUDIOMETRY

27 MODEL 270 INSTRUCTION FOR USE

APPENDIX 1 - SPEECH AUDIOMETRY

The Model 270 audiometer may be used in the following speech modes of operation. However users should be aware
that there is a growing body of professional opinion that Live Voice speech audiometry is generally not recommended.
For recorded speech audiometry, only material with a stated relationship with the calibration signal should be used.
Softkey 1 switches between MIC1 (live) or LINE (recorded) inputs.

Notes regarding the use of recorded test material:

• The audiometer line input is intended for connection to audio playback devices able to output signals having

the industry standard line level voltage amplitude of 0.707Vrms.

• Using other types of output (i.e. headphone sockets, laptop audio sockets) may result in a reduction of signal

level.

• While some compensation for a reduced level is possible using the audiometer, it is also possible to increase

the signal levels of recorded speech test material by using freely available P.C. software. Contact your
distributor for details.

Headphone and Free Field Testing
Note that the line outputs from the instrument (used for free-field testing) are only active when FREEFIELD is selected.

• If headphone testing is being performed, it is recommended that any attached amplifier should be switched off

• If Free Field testing is being performed, this option must always be selected on the audiometer; this disconnects

headphones, bone vibrator and masking insert outputs, and ensures that the correct calibrated output levels are
achieved

• If free-field equivalent output is required from the headphones in Speech mode this option should be selected (see

Section 3.5.2)

Operator Monitoring
Where an acoustic booth/room is used, a patient microphone is connected to the MIC2 input, while the operator

headset/earpiece is connected to the MONITOR output. The operator listening levels may be adjusted as follows:

• The level of the speech signal is controlled by the  Hz  keys, giving 2dB steps

• The level of the patient's responses is controlled by using the SIGNAL rotary control while pressing and holding

TALKBACK

Test Modes in Speech Audiometry
Initially in speech mode either ear may be selected, with the output level controlled by the SIGNAL rotary control.

Pressing TEST MENU followed by Softkey 1 routes the speech to both ears (Stenger test with speech), with the left
output level controlled by the SIGNAL rotary control and the right output level controlled by the MASK rotary control.
Pressing TEST MENU again returns to the original speech mode.

Display Counter
The Display Counter is available only in Speech mode. Use Softkey 3 to activate the counter. For any given level of

stimulus the display then shows the percentage correct alongside the total number of responses. To use the counter

the operator selects ‘YES’ or ‘NO’ according to the response made by the patient. Pressing Softkey 3 clears the counter

to zero. To exit from the Display Counter screen press Softkey 4. Any results will be saved and further results may be
added to those already established (use Sofkey 3 to activate the counter again).

APPENDIX 1 - SPEECH AUDIOMETRY

28 MODEL 270 INSTRUCTION FOR USE

A1.1 Live Voice Speech Audiometry to Headphones
A1.1.1 Set Up:
a) Connect a microphone to the MIC1 input on the audiometer

b) Press SPEECH and use Softkey 1 to ensure that ‘MIC’ is displayed in capitals (indicating that the external microphone

is selected)

c) The microphone is initially routed to the left earphone. To select the right earphone press RIGHT
d) The input signal is adjusted in 1dB steps by use of the MASK rotary control
e) Input signal adjustment should be made to adjust for the operator’s voice to peak at the 0dB point on the LEVEL dB

bar graph; the earphone output will then be 89dBSPL for a SIGNAL setting of 70 dBHL and 1kHz puretone into an
IEC 318 ear simulator

f) The output level is controlled in 5dB steps by the SIGNAL rotary control

A1.1.2 Procedure:
The operator may now read the required word list to the subject and record the responses; the patient may respond

either by (a) repeating the spoken material or (b) writing the words. If the response is spoken, the operator should press
the TALKBACK key to hear this response (see operator monitoring above).

A1.2 Live Voice Speech Audiometry with Contralateral Masking

A1.2.1 Set Up - as described in A1.1.1 then:

a) Select MASK
b) Speech-weighted masking is now routed to the opposite earphone to that selected
c) The MASK rotary control changes the masking level in 5dB steps
d) If required, readjustment of the input signal level can be accessed by temporarily deselecting the MASK key - then

proceed as in A1.1.1d)

A1.2.2 Procedure:
As described in A1.1.2 but adjusting the masking level as required.
A1.3 Recorded Speech Audiometry to Headphones

A1.3.1 Set Up:

a) Connect a CD, tape player, or other sound source to the LINE IN jack socket; refer to Section 2.7 of this operating

manual

b) Press SPEECH and use Softkey 1 to ensure that ‘LINE’ is displayed in capitals (indicating that the line input is selected)
c) The line input is initially routed to the left earphone. To select the right earphone press RIGHT
d) The input signal is adjusted in 1dB steps by use of the MASK control
e) Play the 1kHz calibration tone on the recorded material and adjust the input signal such that the LEVEL dB bar graph

reads 0dB; the headphone output measured in an IEC 318 ear simulator will now be 89dBSPL for a setting of 70
dBHL

g) The output level is controlled in 5dB steps by the SIGNAL control

APPENDIX 1 - SPEECH AUDIOMETRY

29 MODEL 270 INSTRUCTION FOR USE

A1.3.2 Procedure:

As described in A1.1.2 except that the operator plays the recorded material to the subject.

A1.4 Recorded Speech Audiometry to Headphones with Contralateral Masking
A1.4.1 Set Up - as described in A1.3.1 then:
a) Select MASK

b) Speech-weighted masking is now routed to the opposite earphone to that selected
c) Select INT or EXT masking source using Softkey4 (the option selected is displayed in capitals); internal will be

wideband noise and external will be the competing noise from the signal source

d) The MASK rotary control changes the masking level in 5dB steps
e) If required, readjustment of the input signal level can be accessed by temporarily deselecting the MASK key - then

proceed as in A1.3.1d)

A1.4.2 Procedure:
As described in A1.3.2 but adjusting the masking level as required.

IMPORTANT NOTES – FREE FIELD MODES

For the following Free Field modes of operation it is essential for the Free Field calibration procedure described in
Appendix 2 of this operating manual to have been performed. This aspect may also be subject to local requirements or
legislation.

A1.5 Free Field Live Voice Speech Audiometry

A1.5.1 Set Up:

a) Connect an external amplifier/speaker to the LINE OUT jack socket; refer to Section 2.7 of this operating manual
b) Connect a microphone to the MIC1 input on the audiometer
c) Press SPEECH & FREEFIELD and use Softkey 1 to ensure that ‘MIC’ is displayed in capitals (indicating that the external

microphone is selected)

d) The external microphone is now routed to the external amplifier and speaker; use LEFT and RIGHT to select the

required amplifier channel

e) Continue from Section A1.1.1d) to Section A1.1.1f) above

A1.5.2 Procedure:
As described in A1.1.2.
A1.6 Free Field Recorded Speech Audiometry

A1.6.1 Set Up:
a) Connect an external amplifier/speaker to the LINE OUT jack socket, and a CD, tape player, or other sound source to

the LINE IN jack socket; refer to Section 2.7 of this operating manual

b) Press SPEECH & FREE FIELD and use Softkey 1 to ensure that ‘LINE’ is displayed in capitals (indicating that the line

input is selected)

c) The line input is now routed to the external amplifier and speaker; use LEFT and RIGHT to select the required

amplifier channel

d) Play the 1kHz calibration tone on the recorded material and follow the calibration procedure in Appendix 2
e) The input signal is adjusted in 1dB steps by use of the MASK control
f) Adjust the input signal such that the LEVEL dB bar graph reads 0dB

APPENDIX 1 - SPEECH AUDIOMETRY

30 MODEL 270 INSTRUCTION FOR USE

A1.6.2 Procedure:
As described in A1.3.2

A1.7 Free Field Recorded Speech Audiometry With Competing Noise (Audiometer-Generated)
A1.7.1 Set Up: - as described in A1.6.1 then:
a) Select MASK

b) Select internal masking source using Softkey4 (the INT option is displayed in capitals); wideband noise is routed to

the competing LINE OUT channel

c) The level of competing noise is adjusted in 5db steps using the MASK rotary control

A1.7.2 Procedure:
As described in A1.3.2 but adjusting the competing noise level as required.

A1.8 Free Field Recorded Speech Audiometry With Competing Noise (Recorded)

A1.8.1 Set Up: as described in A1.7.1 except:
a) Select external masking source using Softkey4 (the EXT option is displayed in capitals); competing noise from the

signal source is routed to the competing LINE OUT channel

b) Use the SIGNAL control to adjust the signal channel and MASK control to adjust the noise channel

A1.8.2 Procedure:
As described in A1.3.2 but adjusting the competing noise level as required.

APPENDIX 2 - FREE FIELD CALIBRATION PROCEDURE

31 MODEL 270 INSTRUCTION FOR USE

APPENDIX 2 - FREE FIELD CALIBRATION PROCEDURE

A2.1 Assurance of Calibration

The following is a brief description of the equipment and procedures to be used with the Model 270 audiometer as a
means of performing free-field calibration.

However it must be emphasised that it is the responsibility of the equipment operator to ensure that correct free-field
calibration has been achieved, and it is recommended that the standards for free-field & speech testing & calibration
(e.g. ISO 8253-3 & ISO 389-7) and other appropriate reference works are consulted.

It is assumed that the room, speakers and listening position have been set up in conformance with the relevant
standards and that the required calibration equipment, operating procedures and trained technical staff are available
to perform this operation. Once calibrated, items should not be moved, removed, or added to the room without re­calibration.

A2.2 External Amplifier and Loudspeaker

The following external equipment is specified for use of the Model 270 audiometer in free-field modes of operation:

• Amplifier: Interacoustics AP70

• Loudspeaker: Interacoustics ALS7

A2.3 Calibration Overview

The following calibration should be performed before any free-field tests are performed, and repeated if any changes
to equipment positions or settings are made, or if there are other changes to the room (e.g. furniture moved). Place the
speaker(s) in the desired position(s), at least 1.5 meters from the subject’s listening position. Refer to the specification
for the test to be performed for correct loudspeaker and subject alignment(s).

For calibration, the measuring microphone of a sound level meter (SLM) is placed at the reference point (the point that
the subject’s head will be located).

The procedures outlined below cover calibration for both speech and warble tone modes of audiometry. If both modes
are to be use then speech calibration must be carried out first. If only warble mode is to be used then only the warble
part of the calibration procedure may be carried out.

However, if speech mode is required later (and a speech calibration is performed) this will invalidate any previous warble
calibration which would then need to be repeated. If warble tones are to be used as a means of equalising the frequency
response in the speech calibration (see Section A2.4.1.1) then this will invalidate any previous warble calibration which
would then need to be repeated when warble tone testing is required.

A2.4 Free-field Speech Calibration

This is carried out in two stages:

1) the speech channel, which contains two elements:

1. an optional equalisation phase

2. a level-setting phase

2) the competing noise channel, which may be omitted if competing noise is not required

APPENDIX 2 - FREE FIELD CALIBRATION PROCEDURE

32 MODEL 270 INSTRUCTION FOR USE

A2.4.1 Calibrating the Speech Channel

A2.4.1.1 Equalisation (Optional)

To perform equalisation, connect an external speech source to the audiometer (e.g. CD or tape player). From the default
(switch-on) condition of the audiometer select SPEECH and FREEFIELD and then play the test signal from the speech
recording. This should either be:

• pink noise used with a third-octave spectrum analyser and the SLM

• third-octave noise bands used with the SLM

Use the SIGNAL control to set the output to 70dBHL, and adjust the external amplifier to give a reading of 90dBSPL as
measured by the SLM at the reference point.

The response should then be checked to be within the following limits (IEC 60645-2:1993 Section 10.1):

Frequency Range (Hz)

Tolerance (dB)

125 to 250

+0/-10

250 to 4000

+3/-3

4000 to 6300

+5/-5

If necessary, adjustments should be made using the amplifier controls or an additional graphic equalizer to achieve this
response.

As an alternative to using an external speech source, the warble-tone calibration method and controls (see Section A2.5)
may be used to achieve this response. Note that this will invalidate any previous free-field warble tone calibration, and
this must be repeated when warble tone testing is required.

A2.4.1.2 Level Setting

The calibration tone from the speech recording should be played and the external amplifier volume control used to give
a reading of 90dBSPL for a 70dBHL instrument setting. Once set, no further adjustment should be made to the external
amplifier or graphic equalizer controls (if used for equalisation).

If more than one set of test recordings is to be used then the following procedure can be used to allow for minor
differences in calibration levels:

• Set up as above for the most commonly used test recording

• Measure the actual listening point level for when playing the calibration tone of each alternative set of test

recordings

• For each alternative set of test recordings produce a correction table (the difference between the actual

listening point level measured and 90dBSPL)

• Apply this correction to the output level of the audiometer while conducting a test to compensate for the minor

difference in calibration level

APPENDIX 2 - FREE FIELD CALIBRATION PROCEDURE

33 MODEL 270 INSTRUCTION FOR USE

A2.4.2 Calibrating the Competing Noise Channel

Refer directly to Section A2.5.2 if a warble tone calibration is not to be carried out. If warble tones are to be calibrated
(or if the warble tone calibration method is used to equalise the speech frequency response) then the competing noise
channel may be calibrated after the warble procedure as the instrument will already be in the appropriate display mode
for this operation.

A2.5 Free-field Warble Tones Calibration

A2.5.1 Entering Free Field Calibration Mode

• Press OPTIONS and then the NEXT key to move through the menu items and access the ‘Set freefield levels’

screen. Press the YES key.

• Press QUIT and you are now presented with the freefield calibration screen for Warble tones.

• The audiometer will now output at 70dBHL from the Left channel.

As reference for the calibration of warble tone sound pressure levels, the values from ISO 389-7, Table 1 are used
(binaural, on-axis).

Freq
[Hz]

125

250

500

750

1000

1500

2000

3000

4000

6000

8000
dB SPL

92

81

74

72

72

70.5

68.5

64

63.5

72.5

81.5

If a calibration of the speech channel has already been carried out:

Adjust the calibration level for the 1kHz, Left channel using the SIGNAL control to reach the SPL level specified above as
measured by the SLM

If a calibration of the speech channel is not required:

The output of the external amplifier should be set in order to achieve the level specified above at 1000Hz (i.e. 72dBSPL)
as measured by the SLM with the audiometer set to 0dB compensation. The amplifier’s level control should not then be
changed.

When 1kHz, Left channel has been calibrated:

At every other frequency the adjustment should then be made as follows to give the above values as measured by the
SLM.

• Change frequency using the  Hz  keys and then adjust the calibration level for the new frequency using

the SIGNAL control to reach the correct level as measured by the SLM

• Repeat the above until all frequencies have been calibrated for the Left channel

• To calibrate the Right channel (if required) press the RIGHT key (do not change the amplifier’s volume control)

• Adjust the calibration for all of the right channel frequencies (including 1000Hz) by using the  Hz  keys and

the SIGNAL control as described above

• To store the levels and leave Free-field calibration mode, press the STORE key

• If required, all calibration levels can be set to a default of zero by pressing Softkey 1 (‘Zero all’) while in free-

field calibration mode

APPENDIX 2 - FREE FIELD CALIBRATION PROCEDURE

34 MODEL 270 INSTRUCTION FOR USE

It is possible that, because of the characteristics of the listening room or test set-up, the calibration levels above cannot
be achieved because the limit of adjustment is reached for one or more frequencies. Re-arrangement of the listening
room may improve the situation, but if not, the following is a possible solution:

• Set all of the frequencies for which calibration can be achieved

• For frequencies where this is not possible, adjust each to be a multiple of 5dBs from the required level

• Produce a correction table for each frequency for which calibration could not be achieved to be applied to the

output level of the audiometer while conducting a test to relate the instrument display to actual output level
from the speakers.

A2.5.2 Calibrating the Competing Noise Channel

This part of the calibration procedure may be omitted if Free-field speech calibration is not required.

• Enter the Free-field calibration mode as described in A2.5.1

• Press the SPEECH key and the display will change to indicate the option to adjust the competing noise

calibration level – the legend “Sp Mask” is used to indicate this

• Without changing the setting on the external amplifier use the SIGNAL control to adjust the level of the

competing noise to 90dBSPL as measured by the SLM using dBA settings.

• Calibrate each channel, pressing the RIGHT and LEFT keys to switch between channels

• If necessary it is possible to switch between speech (competing noise) and warble calibration modes by pressing

SPEECH and WARBLE respectively

• To store the levels and leave Free-field calibration mode, press the STORE key

A2.6 Free-field Live Speech Calibration

Note: as stated in Appendix 1 of this operating manual, users should be aware that there is a growing body of
professional opinion that Live Voice speech audiometry is generally not recommended. Exceptional skill and
concentration are required to achieve accurate and consistent levels.

• Connect a microphone to the MIC1 input on the audiometer

• Press SPEECH and use Softkey 1 to ensure that ‘MIC’ is displayed in capitals (indicating that the external

microphone is selected)

• The input signal is adjusted in 1dB steps with the MASK rotary control

• Input signal adjustment should be made to adjust for the operator’s voice to peak at the 0dB point on the LEVEL

dB bar graph

• If recorded speech has been calibrated no further action is necessary

• If recorded speech has not been calibrated, the volume control of the amplifier should be adjusted so that the

SLM reads 90dBSPL at the listening point with a 70dBHL setting on the instrument; note that this is an
approximate setting only, as it is not possible to produce a true calibration signal in live speech

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION

35 MODEL 270 INSTRUCTION FOR USE

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S
DECLARATION

Guidance and manufacturer’s declaration – electromagnetic emissions

The Model 270 Audiometer is intended for use in the electromagnetic environment specified below. The
customer or user of the Model 270 Audiometer should assure that it is used in such an environment.

Emissions test

Compliance

Electromagnetic environment – guidance

RF emissions

CISPR 11

Group 1
The Model 270 Audiometer uses RF energy only for its

internal function. Therefore, its RF emissions are very low
and are not likely to cause interference in nearby
electronic equipment.

RF emissions

CISPR 11

Class A

The emissions characteristics of this equipment make it
suitable for use in industrial areas and hospitals (CISPR 11
Class A). If it is used in a residential environment (for which
CISPR 11 Class B is normally required) this equipment
might not offer adequate protection to radio-frequency
communication services. The user might need to take
mitigation measures, such as relocating or re-orienting the
equipment.

Harmonic emissions

IEC 61000-3-2

Class A

Voltage fluctuations/flicker
emissions

IEC 61000-3-3

Complies

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION

36 MODEL 270 INSTRUCTION FOR USE

Guidance and manufacturer’s declaration – electromagnetic immunity (1)

The Model 270 Audiometer is intended for use in the electromagnetic environment specified below. The
customer or user of the Model 270 Audiometer should assure that it is used in such an environment.

Immunity test

IEC 60601 test

level

Compliance

level

Electromagnetic environment – guidance

Electrostatic Discharge
(ESD)

IEC 61000-4-2

±8 kV contact

±15 kV air

±8 kV contact

±15 kV air

Floors should be wood, concrete or ceramic
tile. If floors are covered with synthetic
material, the relative humidity should be at
least 30%

Electrical fast
transient/burst

IEC 61000-4-4

±2 kV for power
supply lines

±1 kV for
input/output
lines

±2 kV for power
supply lines

±1 kV for
input/output
lines

Mains power quality should be that of a typical
commercial or hospital environment

Surge

IEC 61000-4-5

±1 kV
differential
mode

±2 kV common
mode

±1 kV
differential
mode

±2 kV common
mode

Mains power quality should be that of a typical
commercial or hospital environment

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION

37 MODEL 270 INSTRUCTION FOR USE

Immunity test

IEC 60601 test

level

Compliance level

Electromagnetic environment – guidance

Voltage dips, short
interruptions and
voltage variations on
power supply input
lines (100V/60Hz &
240V/50Hz)

IEC 61000-4-11

0% UT

(100% dip in UT)
for 0.5 cycle

0% UT

(100% dip in UT)
for 1 cycle

40% UT

(60% dip in UT)
for 5 cycles

70% UT

(30% dip in UT)
for 500ms

0% UT

(100% dip in UT)
for 5 sec

0% UT

100% dip in UT) for

0.5 cycle

0% UT

(100% dip in UT) for
1 cycle

40% UT

(60% dip in UT) for 5
cycles

70% UT

(30% dip in UT) for
500ms

0% UT

(100% dip in UT) for
5 sec

Mains power quality should be that of a
typical commercial or hospital environment.
If the user of the Model 270 Audiometer
requires continued operation during power
mains interruptions, it is recommended that
the Model 270 Audiometer be powered from
an uninterruptible power supply or a battery

Power frequency
(50/60 Hz) magnetic
field

IEC 61000-4-8

30 A/m

30 A/m

Power frequency magnetic fields should be
at levels characteristic of a typical location in
a typical commercial or hospital
environment.

NOTE UT is the a.c. mains voltage prior to the application of the test level

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION

38 MODEL 270 INSTRUCTION FOR USE

Guidance and manufacturer’s declaration – electromagnetic immunity (2)

The Model 270 Audiometer is intended for use in the electromagnetic environment specified below. The customer
or user of the Model 270 Audiometer should assure that it is used in such an environment.

Immunity test

IEC 60601 test

level

Compliance

level

Electromagnetic environment – guidance

Conducted RF

IEC 61000-4-6

Radiated RF

IEC 61000-4-3

10 Vrms

150kHz to
80MHz

10 V/m

80MHz to

2.7GHz

10 Vrms

150kHz to
80MHz

10 V/m

80MHz to

2.7GHz

Portable and mobile RF communications equipment should
be used no closer to any part of the Model 270 Audiometer,
including cables, than the recommended separation
distance calculated from the equation applicable to the
frequency of the transmitter.

Recommended separation distance

d = 1.2√P

d = 1.2√P 80MHz to 800MHz

d = 2.3√P 800MHz to 2.5GHz

where P is the maximum output power rating of the
transmitter in Watts (W) according to the transmitter
manufacturer and d is the recommended separation
distance in metres (m).

Field strengths from fixed RF transmitters, as determined
by an electromagnetic site survey, a should be less than the
compliance level in each frequency range. b

Interference may occur in the vicinity of equipment marked
with the following symbol:

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION

39 MODEL 270 INSTRUCTION FOR USE

Guidance and manufacturer’s declaration – electromagnetic immunity (2)

NOTE 1 At 80MHz and 800MHz, the higher frequency range applies.

NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption
and reflection from structures, objects and people.

a Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and

land mobile radios, amateur radio, AM and FM radio broadcast and TV broadcast cannot be predicted
theoretically with accuracy. To assess the electromagnetic environment due to fixed RF transmitters, an
electromagnetic site survey should be considered. If the measured field strength in the location in which
the Model 270 Audiometer is used exceeds the applicable RF compliance level above, the Model 270
Audiometer should be observed to verify normal operation. If abnormal performance is observed,
additional measures may be necessary, such as re-orienting or relocating the Model 270 Audiometer.

b Over the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.

APPENDIX 3 - EMC GUIDANCE & MANUFACTURER’S DECLARATION

40 MODEL 270 INSTRUCTION FOR USE

Recommended separation distances between portable and mobile RF communications equipment and the

Model 270 Audiometer

The Model 270 Audiometer is intended for use in an electromagnetic environment in which radiated RF
disturbances are controlled. The customer or the user of the Model 270 Audiometer can help prevent
electromagnetic interference by maintaining a minimum distance between portable and mobile RF
communications equipment (transmitters) and the Model 270 Audiometer as recommended below, according to
the maximum output power of the communications equipment.

Rated maximum
output power of

transmitter

W

Separation distance according to frequency of transmitter

m

150 kHz to 80

MHz

d = 1.2√P

80 MHz to 800

MHz

d = 1.2√P

800 MHz to 2.5 GHz

d = 2.3√P

0.01

0.12

0.12

0.23

0.1

0.38

0.38

0.73

1

1.2

1.2

2.3

10

3.8

3.8

7.3

100

12

12

23

For transmitters rated at a maximum output power not listed above, the recommended separation distance d in
metres (m) can be estimated using the equation applicable to the frequency of the transmitter, where P is the
maximum output power rating of the transmitter in Watts (W) according to the transmitter manufacturer.

NOTE 1 At 80MHz and 800MHz, the separation distance for the higher frequency range applies.

NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption
and reflection from structures, objects and people.

NOTE 3 WARNING: Portable RF communications equipment (including peripherals such as antenna cables and
external antennas) should be used no closer than 30cm (12 inches) to any part of the Model 270 audiometer
including cables specified by the manufacturer. Otherwise degradation of the performance of this equipment
could result.

APPENDIX 4 - USE WITH NON-MEDICAL ELECTRICAL EQUIPMENT

41 MODEL 270 INSTRUCTION FOR USE

APPENDIX 4 - USE WITH NON-MEDICAL ELECTRICAL
EQUIPMENT

Any person who connects external equipment to signal input, signal output or other connectors has created a medical
electrical system and is therefore responsible for the system complying with the requirements of clause 16 of IEC 60601­1:2005 (General requirements for basic safety and essential performance).

If connections are made to standard equipment such as printers and computers, special precautions must be taken in
order to maintain medical safety. The following notes are provided for guidance in making such connections to ensure
that the general requirements of clause 16 of IEC 60601-1:2005 are met.

The following signal inputs and outputs on the Model 270 audiometer are electrically isolated to the requirements of
IEC 60601-1 in order to reduce any potential hazard associated with the use of mains-powered equipment connected
to these inputs and outputs:

Socket Label

Socket Type

Typical Connection

DATA

6 pin mini DIN

Printer

LINE IN

3.5mm jack

CD/Tape Player

LINE OUT

3.5mm jack

Amplifier

USB

USB Connector

Computer

External equipment intended for connection to signal input, signal output or other connectors, shall comply with the
relevant IEC or international standards (e.g. IEC 60950, CISPR 22 & CISPR 24 for IT equipment, and the IEC 60601 series
for medical electrical equipment).

Equipment not complying with IEC 60601 shall be kept outside the patient environment, as defined in IEC 60601-1 (at
least 1.5m from the patient).

The operator must not touch the connected equipment and the patient at the same time as this would result in an
unacceptable hazard.

Refer to Diagrams 1 to 5 below for typical configurations of connected peripheral equipment. Refer to Amplivox Limited
at the address given on the front of this user manual if advice is required regarding the use of peripheral equipment.

Diagram 1: Model 270 used with the medically-approved mains adapter

Diagram 2: Model 270 used with the medically-approved mains adapter and printer

Mains outlet

Medical Mains Adapter

Model 270

Mains outlet

Medical Mains Adapter

Model 270

Printer

Mains outlet

Via cable

Adapter printer

42 MODEL 270 INSTRUCTION FOR USE

Diagram 3: Model 270 used with the medically-approved mains adapter and PC

Diagram 4: Model 270 used with the medically-approved mains adapter and CD/Tape player

Diagram 5: Model 270 used with the medically-approved mains adapter and external loudspeaker

Via USB

Mains outlet

Medical Mains Adapter

Model 270

Mains outlet

PC

Adapter PC

Via cable

Mains outlet

Medical Mains Adapter

Model 270

Mains outlet

CD/tape

Adapter CD/tape

Via cable

Mains outlet

Medical Mains Adapter

Model 270

Mains outlet

Loudspeaker (2)

Adapter loudspeaker

D-0116365-J

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