Bose Rf273139_01D TTH Operators Manual Military Rf273139 01D

User Manual: Bose Triport Tactical Headset Series 2 – Bose Product Support

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Page Count: 25

CLASS

RF DWG NO.

273139

REVISIONS

REV DESCRIPTION CHECK ENG DATE

01 ECN-36327:UPDATE FIGURES;

CHANGE NAME TO TTH, UPDATE

EARCUSHION SECTION

VAB AM 11/04

01A UPDATE TO INCLUDE TTH S2 AM 07/10

01B UPDATED TTHS2 TT BATT. LIFE TO 240

HRS. AM 09/10

01C UPDATED TTHS2 VOLT. RANGE AM 07/11

01D VARIOUS UPDATES AM 10/11

APPLICABLE DOCUMENTS:

DOC

LVL DRAFTER

A. MANGIAMELI DATE

02/05/04

FRAMINGHAM, MA 01701-9168

3 CHECKER

J. BROWN

02/27/04 DESCRIPTION MANUAL, OPERATING &

2 ENGINEER

A. MANGIAMELI

02/05/04 MAINTENANCE (TTH & TTH Series 2)

1 RLS TO PROD

SIZE

A FSCM

32108 CLASS

RF DWG NO.

273139 REV.

01D

SHT 1 OF 25

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1. HEADSET FEATURES

The Bose® TriPort® Tactical Headsets (TTH & TTH Series 2) are active noise

reduction (ANR) communication headsets intended to be used by military

passengers of wheeled combat vehicles. The TTH headsets include an earcup

assembly (earcups and napeband) and a cable/microphone assembly. The

headsets adjust to fit various heads using adjustment overhead hook and loop straps

to ensure proper fit for noise attenuation. The cable/microphone can be installed on

either the left or right earcup.

In addition to passive attenuation each earcup contains an independent ANR

system. The ANR system reduces background noise within each earcup. The talk-

thru circuit (TTC) allows for local communication when the headset is either

connected or disconnected from the vehicle. The TTC is a user-selectable feature

and is powered via a single AA size battery in the control module and utilizes the

microphones on the front of each earcup. Each earcup has an independent TTC to

allow left/right localization.

TTH TTH Series 2

Earcup Assembly

• Overhead Strap

• Napeband

• Earcups

Cable/Mic Assy

• Noise-cancelling

microphone

• Control Module

• Vehicle Interface

Connector

NOTE

The control module

design is a key

differentiator between

TTH and TTH Series 2

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2. TECHNICAL INFORMATION

TTH TTH Series 2

Headset can be donned and

doffed without removing

helmet.

3 3

Cable/boom microphone

assembly is replaceable and

can be positioned on left or

right side.

3 3

Mono and stereo versions

available. 3 3

Weight (on head) 16 oz. maximum Same

Spring force (on head) 1.8 lbf. maximum Same

Push-to-talk (PTT) on the

control module 3-position (latched / off /

momentary) toggle type

switch

3-position (latched / off /

momentary) rocker type switch

Talk-through (TTC) User-selectable, Binaural,

up to 240 hours operational

time with one AA alkaline

battery

User-selectable, Binaural,

240 hours minimum

operational time with one AA

alkaline battery

ANR Power / Current Draw 5.5 to 32 VDC / 16 to 220 mA

Fail-safe operation allows 2-

way communications with

loss of voltage input or talk-

through power.

13.5 to 32 VDC / 38 mA Peak

except during turn-on

Fail-safe operation allows 2-

way communications with loss

of voltage input or talk-through

power.

Operating noise environment Up to 95dBA SPL Same

Earphone sensitivity 106 ± 3 dB SPL for a 0 ± 0.1

dBV input Same

Input Impedance 500 ± 10 ohms Same

Boom microphone 150 ± 22.5 ohm Impedance

-70 ± 4 dB sensitivity 150 ± 22.5 ohm Impedance

-70 ± 4 dB sensitivity

Dust proof

Temperature Rating -40oC to +65oC Operating

-57oC to +71oC Storage -40oC to +65oC Operating

-57oC to +71oC Storage

EMI Qualified for fields up to 50

V/m Qualified for fields up to 50

V/m with improved

performance for reduced audio

interference with the latest IED

jamming devices and other

electronics.

Attachment Clip Cable mounted Mounted on the control

module and compatible with

MOLLE webbing. Clip is

removable and may be

attached to either side of the

control module and rotated

into three different positions.

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3. HEADSET CONNECTORS AND CONTROLS

The connectors and controls for the TTH and TTH Series 2 headsets are integrated

into the cable/microphone assembly normally attached to the left earcup of the

headset. The assembly may be mounted on the right earcup if desired.

The control module on the cable/microphone assembly has a three-position push-to-

talk (PTT) switch as well as a two-position talk-thru circuit (TTC) switch as shown in

Figure 2.0b and 2.0c. The PTT switch is mounted on the face of the control module

and is spring loaded to the center (disabled) position with a momentary PTT position

and latched live intercom position. The control module may also be connected to the

communications microphones typically installed on protective masks. When the

external microphone connector is connected, the control module automatically

disengages the headset boom microphone to receive signals from the external

microphone.

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Figure 2.0b TTH Control Module Features

COMPONENT FUNCTION

Microphone Boom and Cable Assembly Transmits user’s voice into intercom or radio

channel

PTT Switch Used when transmitting on and listening to intercom

channel or radio. The latched position allows the

user to communicate on the vehicle intercom.

The OFF (center position allows the user to listen

only.

The Momentary (down) position allows the user to

communicate on the vehicle intercom and the

selected radio. Please note that these function

could vary by intercom. Please consult the intercom

manual.

Vehicle Interface Connector Provides quick-disconnect for operator.

TTC Switch Used to monitor ambient noise environment when

desired.

M42 Gas Mask Microphone Connection Allows M116/G microphone in the M42 gas mask to

be plugged into the headset.

Battery Compartment Contains AA alkaline battery to power TTC.

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In addition to offering all of the same features as the TTH, the TTH Series

2 has been redesigned for better ergonomics with an integrated

attachment clip.

Figure 2.0c TTH Series 2 Control Module Features

COMPONENT FUNCTION

Microphone Boom and Cable Assembly Transmits user’s voice into intercom or radio

channel

PTT Switch Used when transmitting on and listening to intercom

channel or radio. The latched position allows the

user to communicate on the vehicle intercom.

The OFF (center position allows the user to listen

only.

The Momentary (down) position allows the user to

communicate on the vehicle intercom and the

selected radio. Please note that these function

could vary by intercom. Please consult the intercom

manual.

Vehicle Interface Connector Provides quick-disconnect for operator.

TTC Switch Used to monitor ambient noise environment when

desired.

M42 Gas Mask Microphone Connection Allows M116/G microphone in the M42 gas mask to

be plugged into the headset.

Battery Compartment Contains AA alkaline battery to power TTC.

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Vehicle Interface Connector

Desc. Physical Appearance Connection

Pin-out

TTH Series 2 TTH

Monaural

Prior to

Pin Function

Shield

PTT

Ground

(power and audio)

Boom mic

Ground**

Left/Right earcup

audio

Boom mic

Signal**

Power

Binaural

Pin Function

Shield

Contact

Shield

Right earcup

audio

PTT

Ground

(power and audio)

Boom mic

ground**

Left earcup

audio

Boom mic

signal

Power

**Mic ground must be connected to the power/phone ground (pin 3) in the

intercom for the microphone circuit to function.

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4. HEADSET TROUBLESHOOTING

START

PHYSICAL DAMAGE OR

DETERIORATION PRESENT?

CAN AUDIO BE

HEARD THRU TTC?

IS FAULT STILL

PRESENT?

MICROPHONE

TRANSMISSIONS RECEIVED

BY OTHERS?

CAN AUDIO BE

RECEIVED THRU

EARCUPS?

END

CONNECT HEADSET

TO KNOWN WORKING

INTERCOM/RADIO

REPLACE TTC

BATTERY

(pg 14)

IS FAULT STILL

PRESENT?

IS FAULT STILL

PRESENT?

SUBSTITUTE CABLE /

MICROPHONE ASSEMBLY

WITH KNOWN WORKING

ONE

(pg 13)

REPLACE EARCUP

ASSEMBLY

(pg 13)

ENSURE MICROPHONE

CABLE IS FIRMLY

CONNECTED BY

CHECKING RIBBON

CONNECTORS

(pg 13)

REFER TO HEADSET

INSPECTION TABLE

REPLACE EARCUP

ASSEMBLY

(pg 13)

YES

NO NO

REPLACE BOOM

MICROPHONE

ASSEMBLY

(pg 17)

IS FAULT STILL

PRESENT?

YES

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Headset Inspection Table

Component Condition Corrective Measures

Earcup Assembly Check for cracks and other visible damage to the

housing. Replace earcup assembly*

Napeband Check for visible damage. Replace earcup assembly*

Earcushions Check for visible cuts. Check that uniform

pressure does not cause bottoming against

earcup.

Replace earcushions.*

Cloth Scrim in Earcup Check for tears or excessively dirty. Replace scrim*

Cables Check for cuts, kinks, or frayed area on cable. Replace cable/mic assy*

Connectors Check for dents or other physical damage;

Corrosion buildup. Replace cable/mic assy*

Battery Compartment Check for leakage, dents, corrosion buildup or

other physical damage. Replace cable/mic assy*

Boom Microphpone Check for visible damage to microphone

assembly. Replace boom microphone *

TTC Microphones Check for visible damage or blockage of the metal

screens in front of the TTC microphones on the

front of each earcup.

Replace earcup assembly*

* Refer to applicable removal and replacement procedure.

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5. HEADSET COMPONENTS REMOVAL AND REPLACEMENT PROCEDURES

5.1 Moving Cable/Microphone Assembly to Opposite Earcup

a. Removal

1. Using cross-tipped screwdriver loosen three captive screws (3) securing

cable/microphone assembly (2) to earcup assembly (1) and the decorative cover

(5) to opposite earcup assembly (1).

2. Unplug connector connecting the cable/microphone assembly (2) to the jumper

cable coming off the earcup printed circuit board and remove the

cable/microphone assembly.

b. Replacement

1. Plug cable connector from the cable/microphone assembly (2) into the jumper

cable (4) coming off the earcup printed circuit board.

CAUTION

Ensure no wires are pinched during reassembly of the electronics cover

to the earcup assembly.

2. Using cross-tipped screwdriver, secure cable/microphone assembly (2) to the

earcup assembly (1).

3. Using cross-tipped screwdriver, secure decorative cover (5) to opposite earcup

assembly.

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5.2 Earcushion and Scrim Removal and Replacement

Figure 4.2 Earcushion and Scrim Removal and Replacement

a. Removal

1. Remove earcushion (1) from earcup assembly (3) by inserting fingers inside

earcup between scrim (2) and earcushion and firmly pulling out. Remove any

excess tape residue from the earcup surface.

2. Remove scrim (2) after earcushion (1) is removed.

b. Replacement

1. Align scrim (2) and place over screen in earcup assembly (3).

2. Remove and discard release liners (4) from tape on earcushion assembly.

3. Align and set earcushion (1) on earcup assembly (3) and snap in place.

CAUTION

Do not attempt to remove

the earcushion by pulling on

the soft earcushion material.

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5.3 Windscreen and O-ring Removal and Replacement

Figure 4.3 Windscreens and O-ring Removal and Replacement

a. Removal

1. Grasp O-ring (2) between thumb and forefinger and slide O-ring (2) and

windscreen (3) off microphone (1).

2. Separate O-ring (2) from windscreen (3).

CAUTION

When placing windscreen/O-ring on microphone, be careful not to tear windscreen.

b. Replacement

1. Compress closed end of windscreen (3) and place inside O-ring (2) until O-ring is

midway on windscreen.

2. Slide O-ring (2) with windscreen (3) onto microphone (1) and adjust O-ring until

windscreen is secured.

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5.4 Overhead Strap Assembly Removal and Replacement

Figure 4.4 Overhead Strap Assembly Removal and Replacement

a. Removal

Using a hex (Allen type) wrench remove screw (3) securing overhead strap (2) to

earcup assembly (1).

b. Replacement

Place screw (3) through opening in end of overhead strap (2) and use a hex (Allen

type) wrench to secure to earcup assembly (1).

NOTE

The overhead strap

assembly consist of two

hook and loop strap

sections, hooks and loops.

When placing a single

strap at a time make sure

the replacing strap is the

same as the one being

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5.5 Cable/Microphone Assembly Removal and Replacement

a. Removal

1. Using cross-tipped screwdriver loosen three captive screws (3) securing

cable/microphone assembly (2) to earcup assembly (1). Unplug connector

connecting the cable/microphone assembly (2) to the jumper cable coming off

the earcup printed circuit board and remove the cable/microphone assembly.

b. Replacement

1. Plug cable connector from the cable/microphone assembly (2) into the jumper

cable (4) coming off the earcup printed circuit board.

2. Using cross-tipped screwdriver, secure cable/microphone assembly (2) to the

earcup assembly (1).

CAUTION

Ensure no wires are pinched

during reassembly of the

cable/microphone assembly to

the earcup assembly.

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5.6 Alkaline Battery Removal and Replacement

a. TTH Battery Removal and Replacement

1. Using flat-tipped screwdriver, loosen the captive screw on the battery cover and

rotate to open the battery compartment.

2. Remove old battery and insert replacement battery positive end first into the

battery compartment.

3. Close battery cover and tighten screw using flat-tipped screwdriver.

b. TTH Series 2 Battery Removal and Replacement

1. Using flat-tipped screwdriver, loosen the captive screw on the battery cover and

rotate to open the battery compartment. Battery door is connected to the control

module via a stainless steel tether.

2. Remove old battery and insert replacement battery positive end first into the

battery compartment.

3. Close battery cover by inserting the tab on the battery cover into the slot in the

control module and rotating the battery cover closed.

4. Tighten screw using flat-tipped screwdriver.

Captive screw on

battery cover

l M

odu

Observe Polarity

Captive screw on

battery cover +

Control Modu

Observe Polarity

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5.7 Attachment Clip Removed, Replacement or Adjustment (TTH Series 2 ONLY)

a. Removal

1. Using a flat-tipped screwdriver loosen the captive screw securing attachment clip

to the control module and remove clip from the control module.

b. Replacement and Adjustment

1. Attachment clip can be rotated into 3 different positions.

Position 1 Position 2 Position 3

Attachment clip

captive screw

Control Module

Attachment

Clip

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2. Position attachment clip on the control module in the desired orientation. Rotate

the attachment clip 90 degrees in either direction, lining up the square feature on

the control module with the square hold in the attachment clip.

3. Using flat-tipped screwdriver, secure attachment clip to the control module.

Attachment clip

alignment feature

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5.8 Boom Microphone Removal and Replacement

a. Removal

1. Using cross-tipped screwdriver loosen three captive screws (3) securing

cable/microphone assembly (2) to earcup assembly (1). Unplug connector

connecting the cable/microphone assembly (2) to the jumper cable coming off

the earcup printed circuit board and remove the cable/microphone assembly.

2. Unplug the 3-pin connector connecting the boom microphone to the cable

assembly.

3. Remove the e-ring securing the boom microphone in place and remove and

discard the boom microphone.

NOTE

Remove o-rings with

microphone assembly.

O-rings may remain in

barrel when

microphone assembly

is removed.

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b. Replacement

1. Insert microphone through barrel of the plastic housing. Push replacement

microphone with 2 new o-rings into the barrel of the plastic housing and secure in

place with e-ring.

2. Plug 3-pin connector from the microphone assembly into the mating 3-pin

connector on the cable assembly. Ensure connectors are securely seated.

3. Plug cable connector from the cable/microphone assembly (2) into the jumper

cable (4) coming off the earcup printed circuit board.

4. Using cross-tipped screwdriver, secure cable/microphone assembly (2) to the

earcup assembly (1).

CAUTION

Ensure no wires are pinched

during reassembly of the

cable/microphone assembly to

the earcup assembly.

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Appendix A

Additional Technical Information

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Voltage Range

The headset shall operate in one of three different modes as a function of the

applied voltage. The operating modes shall be identified as “Unpowered”, “Low

Power” and “Intercom”, and each mode shall be active with the voltage applied at

the power contacts of the vehicle interface connector.

Operating Mode Voltage Range

TTH TTH Series 2

Unpowered 0.0 – 5.8 VDC 0.0 – 13.5V

Unpowered or Low Power 5.8 – 6.1 VDC --

Low Power 6.1 – 11.0 VDC --

Low Power or Intercom 11.0 – 13.5 VDC --

Intercom 13.5 – 32.0 VDC 13.5 – 32.0 VDC

Over Voltage

The headset shall survive and operate without malfunction when a pulse of

duration 100µs and potential 36V above ground is applied to the power line. The

pulse repetition rate shall not exceed 1 pulse every 10ms.

Ripple and noise

The headset shall operate through and reject power supply ripple up to 2.7V

peak to peak from 300 Hz to 4500 Hz. During exposure to ripple, the headset

shall not product any noise greater than 65 dB SPL.

Intercom Mode Operation (Standard Operating Mode)

When operating at Intercom Mode the headset shall have the following current

draw characteristics under any condition, except during turn-on:

Current Draw

TTH TTH Series 2

At least 40ma but less

than 220 mA peak Less than 38mA

peak

In Intercom Mode, the headset shall have the following functional characteristics:

Functional

Characteristics TTH TTH

Series 2

Active ANR 3 3

Selectable Talk-through 3 3

Powered Output Level 3 3

Powered Frequency

Response

3 3

Active microphone

preamplifier output

3Not

Applicable

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Low Power Mode Operation

When operating in Low Power Mode the headset shall have the following current

draw characteristics on the head in 85dBA red noise:

Current Draw

TTH TTH Series 2

Less than 16mA RMS

and less than 180mA

peak under any

condition, except

during turn-on

Less than 16mA

peak under any

condition, except

during turn-on

In Low Power Mode, the headset shall have the following functional

characteristics:

Functional

Characteristics TTH TTH

Series 2

Active ANR 3

Selectable Talk-through 3 3

Powered Output Level 3

Powered Frequency

Response

Inactive microphone

preamplifier output

3Not Applicable

Unpowered Mode Operation

When operating in Unpowered Mode the headset shall have the following current

draw characteristics on the head in 85dBA red noise:

Current Draw

TTH TTH Series 2

Less than 1mA RMS Less than 1mA RMS

In Unpowered Mode, the headset shall have the following functional

characteristics:

Functional

Characteristics TTH TTH

Series 2

Inactive ANR 3 3

Selectable Talk-through 3 3

Unpowered Output Level 3 3

Unpowered Frequency

Response

3 3

Inactive microphone

preamplifier output

3Not

Applicable

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PTT Switch

The PTT switch shall provide the following function at the vehicle interface

connector:

Switch Position Function

Up, latching PTT line (contact #2) connected to ground

(contact #3) through 470±5% ohms (power

dissipation in this resistor is less than 0.1W)

Center, latching PTT line (contact #2) open circuit

Down, momentary PTT line (contact #2) connected to ground

(contact #3) through 10 ohms maximum

The boom microphone output signal shall not be muted or disconnected from the

vehicle interface connector in any PTT mode. The vehicle interface connector

shall conform to the pinouts described in Section 3.0 of this document.

Input Impedance

The headset shall not cause damage to the intercom audio circuits under any

circumstances. The audio input impedance of the headset assembly shall be as

follows:

Power Mode Audio Input Impedance

Intercom and Low Power 500 ± 10% ohms

Unpowered No less than 10 ohms

Insulation resistance

The insulation resistance of the headset assembly between any interconnection

terminals and any exposed metal cover shall not be less than 10 Megaohms.

Dielectric withstanding voltage

The headset assembly shall withstand, without flashover or breakdown, the

application of a 100Vrms alternating potential of commercial line frequency for 10

seconds.

Crosstalk

The headset assembly shall provide at least 60dB of separation between the

transmit (mic) and the receive (audio input) as well as the transmit (mic) and

power lines.

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Microphone preamplifier output (TTH only)

This section is only applicable to TTH. The TTH Series 2 product design does

not include an integrated microphone preamplifier output circuit.

TTH ONLY: In the Intercom Mode the boom microphone preamplifier circuit shall

provide an output capable of driving 200mVrms into an unbalanced load of

150±10% ohm AC impedance and not less than 300 ohms DC resistance. The

preamplifier shall provide a gain of 24±1dB with any dynamic microphone. The

preamplifier shall have a flat frequency response between 300 to 4500 Hz.

Harmonic distortion shall be less than 5% for an output of 100mVrms in 24dB

gain mode. The preamplifier shall be bypassed in the Low Power and

Unpowered modes.

Microphone Impedance

The electrical impedance of the microphone at any frequency over the range of

400 to 6000 Hz shall be such that the output voltage shall remain -56±4 dBm @

1kHz re. 103 dBSPL when connected to a 150 ohm load impedance.

Talk-through circuit (TTC)

The headset shall incorporate a talk-through circuit to permit monitoring of the

ambient sound field and direction finding. When mounted on a simulated real

head fixture (mannequin), at 22oC, 50% RH the TTC shall produce gain of 0±

6dB when measured in the 500 Hz octave band and an acoustic frequency

response within 0± 8dB when measured in one octave frequencies between 300

and 4500 Hz and corrected for diffuse field response of the fixture.

The talk-through circuit shall limit direct earcup output to between 86dB(A) SPL

maximum and 72dB(A) minimum with the output corrected for the diffuse field

response of the fixture.

The headset assembly shall accept a number 15A (AA) battery per ANSI C18.1

for operation of the TTC. When exposed to 90 dB, 1kHz noise field with a fresh

battery, the TTC shall provide the following battery life:

TTH TTH Series 2

Battery

life 240 hrs

Minimum 240 hrs

Minimum

Audio Output Level

The headset at 22oC, 50% RH shall product an output level of 106±3dB SPL

corrected for the diffuse fields response of the fixture for a 0± 0.1dBV input audio

signal at 500Hz when in either the Intercom or Low Power Mode. With the

headset in the Unpowered Mode, the output level shall be 94±4dB SPL corrected

for the diffuse field response of the fixture in the octave around 500 Hz for a 0±

0.1dBV input audio signal.

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Harmonic Distortion

The harmonic distortion of the earphone assembly in Low Power and Intercom

Modes shall not exceed 5% for a 0± 0.1dBV input at 500 Hz and it shall not

exceed 10% with the input adjusted for an output of 100dB SPL at 500 Hz and

then swept from 300 Hz to 4500 Hz. The harmonic distortion of the earpohone

assembly in Unpowered Mode shall not exceed 5% for a -6± 0.1dBV input at 500

Hz and it shall not exceed 10% with the input adjusted for an output of 94dB SPL

at 500 Hz and then swept from 300 Hz to 4500 Hz.

Talk Through Circuit (TTC)