Sony DIGITAL NOISE CANCELING HEADPHONES... User manual

SONY:
3-278-744-13(1)
Noise Canceling
Headphones
Operating Instructions
Manual de instrucciones
111111111111111111111111111111111111111111111111111111I
MDR-NC500D *3 2 7 8 7 4 4 1 3 *(1)
©2008 Sony Corporation Printed
in Malaysia

English
Before operating the unit, please read this manual
thoroughly and retain it for future reference.
WARNING
To reduce the risk of fire or
electric shock, do not expose this
apparatus to rain or moisture.
To reduce the risk of electrical
shock, do not open the cabinet.
Refer servicing to qualified
personnel only.
The following FCC statement applies only to the
version
of this model manufactured for sale in the
USA. Other versions may not comply with FCC
technical regulations.
This device complies with Part
15 of the FCC
Rules. Operation
is subject to the following two
conditions:
(I) This device may not cause harmful
interference, and (2) this device must accept any
interference received, including interference that
may cause undesired operation.
You are cautioned that any changes or modifications
not expressly approved
in this manual could void
your authority to operate this equipment.
Note: This equipment has been tested and found
to comply with the limits for aClass Bdigital
device, pursuant to Part
15 of the FCC Rules.
These limits are designed to provide reasonable
protection against harmful interference
in a
residential installation. This
equipment generates,
uses, and can radiate radio frequency energy and,
if not installed and used in accordance with the
instructions, may cause harmful interference to
radio communications. However, there is no
guarantee that interference will not
occur in a
particular installation.
If this equipment does
cause harmful interference to radio
or television
reception, which can be determined by turning the
equipment
off and on, the user is encouraged to
try to correct the interference by one
or more of
the following measures:
-Reorient
or relocate the receiving antenna.
Increase the separation between the
equipment
and receiver.
Connect the
equipment into an outlet on a
circuit different from that to which the receiver
is connected.
Consult the dealer
or an experienced radio/TV
technician for help.
Owner's Record
The model number is located on the housing, and
the serial
number is located inside of the earpad,
at the bottom
of the left housing.
Record the serial
number in the spaces provided
below.
Refer to them whenever you call upon
your Sony dealer regarding this product.
Model No.
MDR-NC500D
Serial No. _
For the customers in the USA
RECYCLING LITHIUM-ION
BATTERIES
Lithium-Ion batteries are recyclable.
You can help preserve
our
environment by returning your used
rechargeable batteries to the
collection and recycling location nearest you.
For more information regarding recycling of
rechargeable batteries, call toll free
1-800-822-8837,
or visit
http://www.rbrc.org/
Caution:
Do not handle damaged or leaking
Lithium-Ion batteries.

for stereo mini jacks for dual jacks
Connecting cord with
battery case (supplied)
Monitor microphone
Note
Environmenlal sound might not be heard if the
microphone is covered with your fingers.
You
can continue to usc the unit. evell when the
rechargeable battery in the headphones runs ouL
by connecting the supplied connecting cord with
battery case.
Usc the connecting cord with battery case by
inserting two size AA alkaline balleries.
Notes
•When connecting the cord. insert Ihe plug fully illio Ihe
jack
~o Ih:lIlhe green sign on the melal parl~ cannot be
seen .
•When di~connccting lhe cord. pull il OUi hy holding the
plug. If the cord is pulled forcibly the wire may oreak.
...
2Insert two size AA alkaline batteries.
Make sure of direction. matching the 0
marks in the case with those on the batteries.
Do not usc the headphones when use of
electronic equipment is prohibited. or when use
of personal headphones for in-flight music
services are prohibited.
~o (0 r
How to use the
connecting cord with
the battery case
When using in an
airplane
The supplied plug adaptor can be connected to
the
dual or stereo mini jacks in an airplane.
4Connect the supplied connecting cord
with the battery case to both the
headphones and AV equipment.
Hearing environmental
sound for safety
If the MONITOR button is pressed and held while
the POWER switch is set to ON. playback silences
then you can hear the surrounding environment.
3 Close the lid.
1 Open the lid of the battery case.
Number of POWER indicator
blinks (pink) and beep
sounds
To set the noise canceling mode
manually
You can selthe noise canceling mode manually
(manual noise canceling).
AI Noise Canceling is auseful function that
automatical1y selects one of the noise canceling
modes. This function provides the most effective
noise canceling mode by immediately analyzing
ambient sound componenlS when the AI NC
MODE button is pressed.
~
~ ~ lrn/ POWER
© ® /\'~y.;- ;nd;cator
p.. :l Al NC MODE
button
AI Noise Canceling
A
'~'Tips
When Ihe power of the headphones is IUnled on,
mode A
is set. (Sec "Noise canceling mode types."
for details about Mode A.)
Press the
Al NC MODE button again to resellhe
noise canceling mode if ambient noise has changed.
such as when you move outdoors from aroom.
Noise canceling mode types
1Press and hold the AI NC MODE button
for more than one second.
Sounds ( ;~ J~ J~ ) come from the headphones to
inform you that manual noise canceling is set.
2Press the AI NC MODE button
repeatedly to
change the mode type.
The POWER indicator blinks pink and a
beep(s) sound(s) from the headphones. After
that. the noise canceling mode is set. The
number of POWER indicator blinks and the
beep sounds depends on the mode selected.
See "Noise canceling mode types."
'~'Tips
Mode A is selected when manual noise canceling is
activated.
To change from manual noise canceling
to Al Noise
Canceling. press and hold the
AI NC MODE button
for more than one second. When you hear the sounds
( J~ Jl Jl) to inform you of the change to Al Noise
Canceling. press the
AI NC MODE button again.
Ambient analysis starts and the most effective noise
canceling mode
is set automatically.
c
1Press the Al NC MODE button.
When you press the AI NC MODE button and
the POWER switch is set to "ON". sounds
come from the headphones to inform you that
the unit
has started analyzing ambienl sound
components (approx. 3 seconds).
During analysis, sound reproduction from the
unit is stopped and the POWER indicator
lights in pink.
When analysis is compleled. the most
effective noise canceling mode is set
automatically, and sound reproduction from
the headphones starts.
Mode names
A: Noise mainly in an airplane is effectively reduced.
B: Noise mainly in abus or atrain is effectively
reduced.
C: Noise mainly found in an office environment (Pc.
copier. air ventilation, etc.) is effeclively reduced.
Utilizing the AI Noise
Canceling
•To disconnect the cord. pull it oul by the plug, not
Ihe cord. as the inner conductors lTlay break.
When connecting
to the stereo mini
Jack of the remote
control supplied
with a WALKMAN®,
etc.
*"WALKMAN"' and "WALKMAN"' logo are
registered trademarks
of Sony Corporation.
Headphones r
2Turn on the power on the right side of the
headphones.
The POWER indicator lights up in blue, and a
short beep sounds from the unit.
~ lm/ POWER
©~ lfJ~f;~
3Put on the headphones.
After confirming the cord on the left and the
POWER switch on the right, put on the
headphones.
Adjust the car pads so as to cover your cars.
Tactile dot
(on the left)
'~'TipS
When the banery rUIlS ou!. you can supply the power to
the he;Klphones in one of the following ways:
Connecl the headphones to the AC power adaptor
by
following the steps shown in "Charge the
headphones."
You (:an use the headphones while charging.
Use the supplied connecting cord with battery case.
See "'How
to use the connecting cord with battery
case" for details.
1Connect the headphones to the AV
equipment.
Using your AC power
adaptor abroad
You can use your AC power adaptor in any
country or area that uses 100 V to 240 VAC,
50/60 Hz, by connecting a plug adaptor. If the
country you visit employs a different shaped
socket, use the correct plug adaptor.
Consult your nearest travel bureau for the type of
plug adaptor needed for your trip.
Listening to music
Notes
•When connecting the cord, insert the plug into the
jack until the green portion
of the plug disappcars.
4 Starl playing on the AV equipment
connected to the headphones.
Note
Plnyback is nOI available when there is no
power.
When the rechargeable
battery is low
When the rechargeable battery is low. short beeps
sound from the unit for 8 seconds and the
POWER indicator blinks slowly.
When the battery level is getting lower, a long
beep sounds from the unit for 2 seconds and the
POWER indicator blinks quickly, and all
operations are stopped. Move the POWER switch
to "OFF" in this case.
Usage time*1
Approx.
15 hours*'
AC power
adaptor
(supplied)
Approx. Jhours 'c
Connect the supplied AC power adaptor to the DC
IN 6V jack on the headphones and an AC outlet.
The charge indicator lights up in orange and
charging stat1s.
Note
Use the AC power adaptor supplied with this unit. Do
not usc any Olhcr AC power adaptor since il may
cause
the unillO malfunction.
The headphones contains arechargeable Lithium-
Ion battery. Charge the batte!)' before usc.
~
Polarity of the plug
Avoid exposure to temperature extremes. direct
sunlight. moisture. sand. dust or mechanical shock.
Neve~r leave in acar parked in the sun
Connect
the AC power adaptor to an easily accessible
AC outlet. Should you nOlice an abnormality in the
AC power adaptor. disconnect it from the AC out lei
immedimely.
Do not install the
AC power adaptor in aconfined
space. such as abookcase or built-in cabinet.
To reduce
the risk of fire or electric shock. do not
place objects filled with liquids. sllch as vases. on the
AC power adaptor.
Charge
in an environmental temperature of between
O°C and 40°C (between ~2°F and 104°Fl. Otherwise.
the banery may not be fully chargcd
If you haven'l used the headphones for along period
of time. the life of the rechargeable banery may
become short. This will improve when you repeat the
charging and discharging process several times.
When
the banery life reduces to hall'. this may be the
end of baltery lifetime. For how
to change halteries.
consul! your place of purchase or aSony dealer.
Do not store Ihe headphones in hot places for ;1 long
period of time. When storing
it for more than ayear.
charge
Ihe banery once ayear 10 prevent over
dischargc
You cannot charge Ihe rechargeable ballery using the
supplied connec!ing cord with baltery case.
Charging time
Digital equalizer delivers ideal frequency
response and high-quality music
reproduction.
High SIN
ratio achieved through digital
signal processing.
Lightweight design creates extremely
comfortable wearing fit.
Generous usc of lightweight materials such as
Magnesium and A7075 aluminum alloy.
Pressure relieving urethane cushion in
the earpad.
The carpad structure provides comfort without
stress cven after extended usc.
General charging and usage time
f
To an AC6et _ IlO~'--..©
~~
I~-
To DC IN
6V Jack -'?
Charge
indicator
Built-in monitor function lets you
silence the audio to listen outside.
Digital noise canceling headphones
with Sony's unique DNC Software
Engine.
Creation of ahigh-precision canceling signal
delivers outstanding noise canceling
performance.
AI (Artificial Intelligence) Noise
Canceling function.
Automatic selection of the optimal noise
canceling mode based on intelligent analysis of
environmental ambient noise.
Charging is completed after about three hours.
and the charge indicator goes oul.
Disconnect the AC power adaptor after the
charging has finished.
'I At 1kHz. 0.1 mW + 0.1 mWoutput
.: Hours required to fully charge an empty ba!lery
_.1 Timc stated above may vary. depending all ambicnt
tempermure or conditions of lISC.
Features
Charge the headphones

General
Type Closed dynamic
Driver unit 40
mm. dome type (CCA Wadopted)
Power handling capacity
lOOmW
Impedance 40 Q at IkHz
Sensitivity 102
dB/mW
Frequency response
5424,000 Hz
Total Noise Suppression Ratio*1
Approx. 20 dB*1
Power source DC 3.7 V: Built-in lithium-ion
rechargeable baue!)',
2xLR6 (size AA) baueries. or AC
power adaptor
Mass Approx. 195 g(6.9 oz)
Design and specifications are subject to change
without notice.
Specifications
No operation works
Set the POWER switch of the headphones to
"OFF," confirm the connections, and then set
the POWER switch back to "ON."
Reset the headphones.
•Insert a pointed object, such as the tip of a
clip, into
the hole located under the RESET
button on the right housing, and press until
the button slightly rebounds.
Supplied accessories
Connecting cord (0.5 m, gold plated stereo mini
plug) (I)
Connecting cord (1.5 m, gold plated Ltype stereo
mini plug) (I)
Connecting cord with battery case (I)
Carrying case (I)
Plug adaptor for in-flight use*3 (single/dual) (I)
Gold-plated unimatch plug adaptor (stereo phone
plug +-+ stereo mini jack) (I)
Sony LR6 (size AA) batteries (2)
AC power adaptor (1)
Operating Instructions (I)
Product Information (I)
Startup guide (I)
Card warranty (I)
*J Under the Sony measurement standard.
For details about the Total Noise Suppression
Ratio amount for each mode, refer to the
Product Information booklet.
*2 Equivalent to approx. 99 % reduction of energy
of sound compared with not wearing
headphones (NC MODE A).
*3 May not be compatible with some in4flight
music
services.
Precautions
Troubleshooting
What is noise canceling?
The noise canceling circuit actually senses outside
noise with built-in microphones and sends an
equal-but-opposite canceling signal to the
headphones.
Note on headphones
Preventing hearing damage
Avoid using headphones at high volume. Hearing
experts advise against continuous, loud and
extended play. If you experience aringing in your
ears, reduce the volume or discontinue use.
If you have any questions or problems
concerning the system that are not covered in
this
manual, please consult your nearest Sony
dealer.
The headphones contain a noise canceling circuit.
No sound
Turn on the headphones.
When connecting the connecting cord with
battery case, turn on the power of the battery
case.
Check that the rechargeable battery is not
depleted.
When connecting the connecting cord with
battery case, check that the batteries have not
expired.
Check the connection of the headphones and
the AV equipment.
Check that the connected AV equipment is
turned on.
Turn up the volume of the connected AV
equipment.
The noise canceling effect may not be
pronounced in avery quiet environment, or
some noisc may be heard.
Thc noise canceling effect may vary depcnding
on how you wear the headphones.
The noise canceling function works for noise in
the low frequency band primarily. Although
noise is reduced, it is not canceled completely.
When you use the headphones in atrain or a
car. noise
may occur depending on street
conditions.
Howling may occur if you do not wear the
headphones correctly.
Howling may occur if you place an object such
as finger close to inside of the headphones.
Keep it away from the headphones.
Mobile phones may cause interference and
noise. To avoid interference, use noise
canceling feature only with wireless
transmitters turned off (Airplane Mode).
Interference noise can also occur from nearby
mobile phones. Should this occur, locate the
headphones further away from the mobile
phone.
Notes on usage
Clean the headphones with asoft dry cloth.
Do
not leave the plug dirty otherwise the sound
may be distorted.
Be sure to consult a Sony dealer when the
earpads become dirty or damaged, or when the
headphones require repair work.
Do not leave the stereo headphones in a
location
subject to direct sunlight, heat or
moisture.
Do not listen with the headphones while
driving or cycling
As your headphones reduce surrounding sound, it
may cause atraffic accident. Also avoid using
them where hearing must not be impaired, for
example, at a railroad crossing, a construction
site, etc.
Power does not turn on
Check if the battery has expired (the POWER
indicator dims) .
•
[f the power does not turn on, even after
charging the headphones. the rechargeable
battery may be damaged. Consult your place
of purchase or a Sony dealer in this case.
Replace the alkaline batteries in the battery
case with new ones.
Muffled sound
Turn down the volume of the connected AV
equipment.
Charge the headphones.
Replace the alkaline batteries in the battery
case with new ones.
Connector
The unit contains arechargeable Lithium-Ion
baltery. For environmental conservation. be sure
to remove the built-in rechargeable batteries from
the unit
before disposing. and dispose of the
hatteries appropriately.
Disposing of the unit
1Pull ofT the earpad on the left housing.
and unwind the two screws located as in
the illustration.
Note
Be careful not to break the internal wires.
Note
Be careful not to break the internal wires
when disconnecting the connector.
2 Turn down the left housing and pull off
the outer cover.
Note
Remove (he rechargeable battery. taking care
not (0 damage it.
3Keep the cord away from the rechargeable
battery.
First. remove the adhesive tape on the surface
of the batlery. Then. loosen the cord just
beside the rechargeable battery.
4Pull out the connector on the board.
5 Remove the rechargeable battery.
The rechargeable battery is firmly installed by
adhesive tape. Take out the rechargeable
battery by lifting up in the direction of the
arrow shown in the illustration.
10 hours <>
Approx. hours*1
Battery life
Son vAlkaline
LR(; (size AA) b .. lIery
Battery type
'Q'Tips
The power supply of ,he n.:ch;lrgeable hattery is
consullled firs!. unless the b,lllcry runs oul.
If you connect and turn on the cOlmccling cord with
the hanery (,:asc in "dv,mel.' when the rcchargeahk'
haltery is low. you can usc the headphones
uninterrupted, even after the ballcry in the
headphones runs oul.
See sleps 2 104 of "Listening 10 music" for
the following selling sleps.
At"cr use. SCi the POWER switch of both the
headphones and the ballcry case to ;'OFF:'
The housings rotate to make them flat for easy
storage
in the carrying case (supplied), or in ascat
pocket. Restore to their usual position before using.
5Set the POWER switch of the
headphones
to "OFF:' and then set the
POWER switch of the battery case to
"ON."
The POWER indicator on the battery case
lights up green. ?
POWER switch -e ~
POWER indicator ---;+~
Note
Because the supplied bauery was included in the
package from the time
of manufacture (as a
convenience to the user).
it is possible thai the
battery life may be
somewhat depleted hy the time
of purchase. The actual life of the supplied battery
may be shorter than the standard lime described in
this manual
when using afresh hattery.
Turn oil the power of the headphones.
After use
'I Output:.ltl kHz.O.lIllW+O.1 mW
': Time Slated .. hove may vary. <.Iepl:"nding ou ambient
tel11perawre or conditions of use.
Notes
The use of manganese batlcril's is nol recolllillended.
since this type of banery has an extremely short
usae.ctll11C
1'h .... -battery case supplies the power to Ihe
headphone:-. for operation purposes only. It docs not
charge the internal reehargcable battery in the
headphones.
The
POWER indil'alor of the battery case becomes
dim when the baltery life is readling the limit
Replace the ballery with
new ones at the time.
The supplied connecling cord with ballery case
is
only for the$e headphones. Do not connect to mher
equipment.
Flat Storage
Putting the headphones
in the carrying case
Rotate the housings to be flat before putting them
in lhe carrying case.

SONY:
3-280-434-12(1)
Noise Canceling
Headphones
Product Information ----Jm
Informations concernant Ie produit Ii3I
Produktinformationen m
Informaci6n del producto III
Informazioni sui prodotto D
Informa<;6es sobre 0produto 61
MDR-NC500D
©2008 Sony Corporation

Content
I. Introduction 4
2. Principle of Operation of MDR-NC500D and Its Configuration 5
2.1. Feedback Type and Feedforward Type 6
2.2. System configuration
of MDR-NC500D 7
2.3. Advantages
of Digitization 8
3. AI Noise Canceling Function 9
3.1. Operation of AI Noise Canceling function 10
4. Specialized Driver Unit 10
5. High-Quality Sound Unique to Digital 11
6. Weight saving mechanism 12
7. Other Features 13
7.1. Monitor function 13
7.2. Swivel mechanism 13
7.3. Detachable connecting cord 13
7.4. Power supply 13
7.5. High-quality sound BTL headphone amplifier 13
Appendix: Indication of Canceling Performance
for Noise Canceling Headphones
14
1.1. Total Noise Suppression Ratio 14

1. Introduction
MDR-NC500D is the Digital Noise Canceling Headphones, which Sony developed as the
first
of their kind in the world.
For this development, Sony put in all of its acoustical analysis technology, digital signal
processing technology and transducer technology.
By digitizing the noise canceling function, we succeeded in improving the performance in
the following points which, were difficult to be addressed with the conventional analog signal
processing:
•High canceling performance
•AI (Artificial Intelligence) Noise Canceling function
•Excellent sound quality
•Higher Signal to Noise ratio

2. Principle of Operation of AfDR·NC500D
and Its Configuration
The noise canceling headphones make acanceling signal by analyzing with their noise
canceling circuit the surrounding noise collected by the small noise detection microphone built
in their main body.
With this canceling signal superimposed on the regenerative signal from the connected
equipment, reproduction from the driver unit reduces surrounding noise and makes it possible
to listen to music more clearly.
+
1. Waveform of noise
(original sound)
Surrounding noise is collected by
the noise detection microphone
built
in the headphones and its
signal is analyzed with the noise
canceling circuit.
2. Inverted sound
waveform
The inverted sound, which can
negate the analyzed noise, is
generated.
3. Sound waveform
canceled by
superimposition
By overlaying the original sound
with the inverted sound, the
original sound is negated. This
reduces noise at the eardrum.
For the noise canceling, the following two methods are mainly used:
•Feedback type
•Feedforward type
Continued
5GB

!leaH: ~
2.1. Feedback Type and Feedforward
Type
Feedback type
The noise canceling function of the "feedback type" is used in MDR-NC500D.
In the feedback type, the noise detection microphone is placed close to the ear.
By collecting noise
in the position closer to the ear, anoise canceling effect with high
accuracy can be obtained.
The audio signal
of noise collected by the noise detection microphone is analyzed on real
time with the noise canceling circuit (NC circuit), producing acanceling signal
to always
minimize the noise at the eardrum. The canceling signal is reproduced from the driver unit.
Using this method enables the cancellation effect to be increased with the changing
environmental noise addressed.
Feedforward type
In the feedforward type, the noise detection microphone is attached outside the
headphones.
The NC circuit analyzes the noise signal collected by the noise detection microphone to
estimate what kind
of sound the noise will become when it comes to the eardrum. And from
this estimated result, acanceling signal to minimize the noise
is made and it is reproduced
from the driver unit.
This type enables miniaturization
of the headphones since it is not necessary for the noise
detection microphone to be located near the ear where space is limited.
Noise detection
microphone
Noise
Feedback type
Noise
Feedforward type

Comparison between Feedback Type and Feedforward Type
Feedback type Feedforward type
Noise canceling effect Excellent Good
Anti dependency of noise
canceling effect against Better Average
individual difference /fitting
difference
Miniaturization Less suitable More suitable
2.2. System configuration of MDR·NC500D
The Internal Block Diagram of MDR-NC500D is shown below:
AID
converter
---+
Audio In
·
·
·
·
·
·
·
----'
,
·..
"'-.''''. -
Headphone
"~::rt,, -+i>~[(]
Driver unit
'-<J~ction
'--:-:-----' Microphone microphone
••••••••• ~ ••• , •• ~ ••••. 'amplifier
Internal Block Diagram of Noise Canceling
Headphones of
MDR-NC500D
The noise detection microphone of MOR-NC500D collects noise
around the ear.
The noise signal is digitized through the microphone amplifier and
high-speed
AID converter and is inputted in Digital Signal Processor
(OSP). Then the DNC software engine inside
DSP generates the canceling
signal, which is inverted to the original noise.
Meanwhile, the regenerative signal
of amusic source supplied from
the audio input terminal is digitized by the high-speed
AID converter and is
inputted in DSP. Then, its frequency characteristic is adjusted by the digital
equalizer inside OSP. After the canceling signal is added, the regenerative
signal
is reproduced as asound by way of the high-speed 01Aconverter,
the headphone amplifier and the driver unit.
Mixing
of the reproduced sound and the outside noise at the ear
negates only environmental noise, making it possible to enjoy music etc.
calmly.
•
High-speed AID,
D/A converter
Continued

_ 7 _ _ "
2.3. Advantages of Digitization
The performance of noise canceling headphones greatly depends on the efficiency of the
filter circuit (NC filter) between the microphone to detect noise and the driver unit
to
reproduce the canceling signal.
In MDR-NC500D, the filter circuit for noise canceling is realized on the
DSP as the
digital signal processing
of the newly developed "DNC software engine."
In addition to general advantages such as accurate computation results, no theatrical
variation, and no electric noise, the digital signal processing has also the advantage
of making
it possible to create special filter shapes, which were not able to be realized with existing
analog filters.
During the development
of the DNC software engine, the architecture of internal filter
computation was thoroughly examined in order to implement amore effective noise canceling.
The know-how
of Sony's digital sound treatment was used to construct asoftware engine
specialized in the noise canceling treatment and the calculation accuracy was heightened.
Noise canceling with less residual noise and higher Signal
to Noise ratio was made possible.
Example of the characteristic of
conventional NC filter Example of the characteristic of digital NC filter
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Frequency Frequency

3.AI Noise Canceling Function
tMll Illll
The characteristics of environmental noise vary with the scene to be used.
In an airplane, for example, low and midrange frequencies can have alarge noise energy
and other frequency ranges have asmaller noise energy.
On the other hand,
in the environment such as an office, the noise energy is small but
distributed over awider range.
In MDR-NC500D, the filter circuit to control anoise canceling ratio was digitized and it
is controlled by software.
This enables the filter characteristic to be switched: AI Noise Canceling function with
which MDR-NC500D selects automatically the filter characteristic (noise canceling mode) that
is the most suitable for the user's environment.
AI Noise Canceling function
Digital technology allows selection from multiple
noise canceling modes.
The headphones analyze the outside noise and
automatically select the optimal canceling mode.
_0_" A -- B ------. C
Frequency
,
/0 ,,'
/" ,,'
to ,,'
(/C
--r
I
I
\ I
\ jA
'...,0
Noise canceling ratio
*Manual mode selection is also possible.
NC MODE A
Noise mainly in an airplane is effectively
reduced.
~
NC MODE B
Noise mainly in abus or atrain is effectively
reduced.
NC MODE C
Noise mainly found in an office environment
(PC, copier, air ventilation, etc.) is effectively
reduced.
Continued
9
GB

3.1. Operation of AI Noise Canceling function
The operation of actual AI Noise Canceling function is as follows:
1. Press the AI NC MODE button to start the analysis program. *
2. Built-in DSP analyzes the sound information of noise from the noise detection
microphone.
Its specific value
is extracted from the signal and the most effective noise canceling
mode is selected.
3.
The noise canceling operation is started in the selected mode.
*During analysis, reproduction
of music source and noise canceling function are temporarily stopped in order to
gather exact noise information.
MDR-NC500D completes the above-mentioned processing
in ashort time
of about 3seconds.
The analysis algorithm of AI Noise Canceling (ATNC)
developed aproprietary calculation technique based on the
Auditory psychology emphasizing the frequencies, which make
noise more audible to the ear.
It is the very realization
of "smart headphones" which can
follow man's feeling.
With the AI Noise Canceling function only made possible
by Digital, please enjoy its comfortable canceling effect.
4. Specialized Driver Unit
Tn order that feedback type headphones obtain
awider canceling range, it is necessary to minimize
the time delay between the output
of the driver unit
and the input to the noise detection microphone.
By integrating the noise detection microphone
with the driver unit to minimize the time delay,
MDR-NC500D achieved astable and wider range
canceling performance.
Moreover, the use
of re-informed diaphragm
significantly improved the canceling performance
against environmental noise with ahigh sound
pressure that
is generated in avery low frequency.
10
GB
DSP used in
MDR-NC500D
Driver unit

5. High-Quality Sound Unique to Digital
MDR-NC500D digitized the NC circuit and used the digital equalizer in the playback
system.
The acoustical system
of noise canceling headphones is generally based on the design,
which emphasizes low frequency in order to maximize the effect with limited electric power.
Moreover,
in the case of the noise canceling headphones of feedback type, in principle
their music signal is impacted by the canceling function, so that the quality
of the reproduced
sound is also impacted.
To solve these problems, an equalizer circuit is prepared in the audio input side.
The digital equalizer mounted in MDR-NC500D blocks the impact on the sound quality
and also brings about high-quality sound to maximize the intrinsic performance
of the driver
unit. By generously providing the digital equalizing technology accumulated with
Sony's AV
amplifiers and Hi-Fi audiovisual apparatus and using the newly developed computation
method optimized to the system,
it was made possible to reproduce amusic source with a
sense
of realism from deep bass to silky highs.
Characteristic of
acoustical system Characteristic of
digital equalizer Total characteristic
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Desired
characteristic
Frequency Frequency Frequency

6. Weight saving lI1echanislI1
,
Magnesium and 7075 aluminum are used as the material for the housing and the
headband, respectively.
By using these unstintingly, the mass is reduced to as small as 195 g or more than 10 %
weight reduction. *
* In comparison with MDR-NC60.

7. Other Features
IUt/Uk
7.1. Monitor function
MDR-NC500D is equipped with the monitor function to make the surrounding sound
more audible by muting music etc. during reproduction when you are spoken to, for example.
While wearing the headphones, you can hear an announcement etc. in an airplane or in a
train only by pressing the button.
During monitoring, disturbing noise can be reduced by the noise canceling function.
7.2. Swivel mechanism
Amechanism to reduce the storage thickness by rotation of the housing is used in order to
enhance portability. (Swivel mechanism)
7.3. Detachable connecting cord
The main body side of the headphones connecting cord is detachable.
According to the equipment in combination, you can select the connecting cord of optimal
length from accessories. When using the noise canceling function without any music playback,
etc., disconnect the cord for comfortable use.
Moreover, the connecting cord with battery case also serves as power source.
MDR-NC500D can be used longer in combination with the built-in lithium ion
rechargeable battery.
7.4. Power supply
MDR-NC500D supports three kinds of power supply methods: Built-in lithium-ion
rechargeable battery, Alkaline LR03 (size AA) battery
*1 and AC power adaptor.
The AC power adaptor is of 100 Vto 240 Vmulti-voltage type.
It can be used almost all over the world. *2
*1 When the connecting cord with battery case is used. Two Alkaline LR03 (size AA) batteries are used.
*2 Use with the outlet of adifferent shape needs an optional plug adapter.
7.5. High-quality sound BTL headphone
amplifier
The headphone amplifier is of BTL (Bridged Transformer-Less) type.
You can enjoy apowerful sound with awide dynamic range.

Appendix: Indication of Canceling Performance
for Noise Canceling Headphones
1.1. Total Noise Suppression Ratio
Total Noise Suppression Ratio (TNSR) of noise canceling headphones is expressed with
the following formula:
TNSR =10 log (P I Po)
• Po =Energy of sound observed at the ear not wearing headphones
• P =Energy
of sound observed at the ear wearing headphones
*The above energy of sound measurements are weighted.
TNSR is the value measured using the noise signal based on abroad spectrum.
As compared with the method
of measuring the noise canceling ratio at acertain point of
frequency, TNSR enables the canceling performance in the actual usage environment to be
more objectively evaluated.
Moreover, it can evaluate the canceling performance in each noise environment by using
the signals
to simulate the spectrum distribution of real-world noise such as an airplane and a
train.

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[Sony's conventional method]
Noise before
Wearing (ON) wearing
----. Frequency
INoise canceling ratio =Difference between
ON and OFF
Largest value (one point)
Q)
:;
VI
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[Total Noise Suppression Ratio (TNSR)]
----. Frequency
Total Noise Suppression Ratio =Difference in noise energy
when not wearing the
headphones and when the
Noise Canceling function
is
active.
[Example of notation]
TNSR: 20 dB
Total Noise Suppression Ratio (typical values) Unit: dB
Airplane Train/Bus Office
NC MODE A20.0 18.0
17.1
NC MODE B17.0 20.3 18.3
NC MODE C14.9 15.0 18.9
•Based on Sony's one noise source simulations.
•Note: Noise canceling ratio
(Sony's conventional method) more than 25 dB (at MODE A)

Printed in Malaysia
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