Teac AI-303 User manual

Z
ENGLISH
FRANÇAIS
ESPAÑOL
AI-303
USB DAC AMPLIFIER
D01395520A
OWNER’S MANUAL
MODE D’EMPLOI
MANUAL DEL USUARIO

2
CAUTION: TO REDUCE THE RISK OF ELECTRIC
SHOCK, DO NOT REMOVE COVER (OR BACK).
NO USER-SERVICEABLE PARTS INSIDE.
REFER SERVICING TO QUALIFIED SERVICE
PERSONNEL.
<The lightning flash with arrowhead symbol,
within an equilateral triangle, is intended
to alert the user to the presence of unin-
sulated “dangerous voltage” within the
product’s enclosure that may be of suf-
ficient magnitude to constitute a risk of
electric shock to persons.
BThe exclamation point within an equilat-
eral triangle is intended to alert the user to
the presence of important operating and
maintenance (servicing) instructions in the
literature accompanying the appliance.
WARNING: TO PREVENT FIRE OR SHOCK
HAZARD, DO NOT EXPOSE THIS APPLIANCE
TO RAIN OR MOISTURE.
CAUTION
oDO NOT REMOVE THE EXTERNAL CASES OR CABINETS TO
EXPOSE THE ELECTRONICS. NO USER SERVICEABLE PARTS
ARE INSIDE.
oIF YOU ARE EXPERIENCING PROBLEMS WITH THIS
PRODUCT, CONTACT THE STORE WHERE YOU
PURCHASED THE UNIT FOR A SERVICE REFERRAL. DO
NOT USE THE PRODUCT UNTIL IT HAS BEEN REPAIRED.
oUSE OF CONTROLS OR ADJUSTMENTS OR
PERFORMANCE OF PROCEDURES OTHER THAN THOSE
SPECIFIED HEREIN MAY RESULT IN HAZARDOUS
RADIATION EXPOSURE.
IN USA/CANADA, USE ONLY ON 120V SUPPLY.
1) Read these instructions.
2) Keep these instructions.
3) Heed all warnings.
4) Follow all instructions.
5) Do not use this apparatus near water.
6) Clean only with dry cloth.
7) Do not block any ventilation openings. Install in accor-
dance with the manufacturer's instructions.
8) Do not install near any heat sources such as radiators,
heat registers, stoves, or other apparatus (including
amplifiers) that produce heat.
9) Do not defeat the safety purpose of the polarized or
grounding-type plug. A polarized plug has two blades
with one wider than the other. A grounding type plug
has two blades and a third grounding prong. The wide
blade or the third prong are provided for your safety. If
the provided plug does not fit into your outlet, consult
an electrician for replacement of the obsolete outlet.
10) Protect the power cord from being walked on or
pinched particularly at plugs, convenience receptacles,
and the point where they exit from the apparatus.
11) Only use attachments/accessories specified by the
manufacturer.
12) Use only with the cart, stand, tri-
pod, bracket, or table specified
by the manufacturer, or sold with
the apparatus. When a cart is
used, use caution when moving
the cart/apparatus combination
to avoid injury from tip-over.
13) Unplug this apparatus during lightning storms or when
unused for long periods of time.
14) Refer all servicing to qualified service personnel. Servicing
is required when the apparatus has been damaged in any
way, such as power-supply cord or plug is damaged, liquid
has been spilled or objects have fallen into the apparatus,
the apparatus has been exposed to rain or moisture, does
not operate normally, or has been dropped.
oThe apparatus draws nominal non-operating power
from the AC outlet with its POWER or STANDBY/ON
switch not in the ON position.
oThe mains plug is used as the disconnect device, the
disconnect device shall remain readily operable.
oCaution should be taken when using earphones or
headphones with the product because excessive sound
pressure (volume) from earphones or headphones can
cause hearing loss.
WARNING
Products with Class !construction are equipped with a
power supply cord that has a grounding plug. The cord
of such a product must be plugged into an AC outlet that
has a protective grounding connection.
IMPORTANT SAFETY INSTRUCTIONS

3
CAUTION
oDo not expose this apparatus to drips or splashes.
oDo not place any objects filled with liquids, such as
vases, on the apparatus.
oDo not install this apparatus in a confined space such
as a book case or similar unit.
oThe apparatus should be located close enough to
the AC outlet so that you can easily reach the power
cord plug at any time.
oIf the product uses batteries (including a battery pack
or installed batteries), they should not be exposed to
sunshine, fire or excessive heat.
oCAUTION for products that use replaceable lithium
batteries: there is danger of explosion if a battery is
replaced with an incorrect type of battery. Replace
only with the same or equivalent type.
V Precautions concerning batteries
Misuse of batteries could cause them to rupture or leak lead-
ing to fire, injury or the staining of nearby things. Please read
and observe the following precautions carefully.
oBe sure to insert the batteries with correct positive (¥)
and negative (^) orientations.
oUse batteries of the same type. Never use different types
of batteries together.
oIf the remote control is not used for a long time (more
than a month), remove the batteries to prevent them
from leaking.
oIf the batteries leak, wipe away the leakage inside the
battery compartment and replace the batteries with
new ones.
oDo not use batteries of types other than those specified.
Do not mix new batteries with old ones or use different
types of batteries together.
oDo not heat or disassemble batteries. Never throw bat-
teries into fire or water.
oDo not carry or store batteries with other metallic
objects. The batteries could short circuit, leak or explode.
oNever recharge a battery unless it is confirmed to be a
rechargeable type.
oDo not expose batteries to extremely low air pressure as
it could result in an explosion or leakage of flammable
liquids or gases.
Supplier’s declaration of conformity
Model number: AI-303
Trade name: TEAC
Responsible party: 11 Trading Company, LLC
Address: 3502 Woodview Trace #200 Indianapolis, IN46268
U.S.A.
URL: https://11tradingcompany.com/contact-us/
This device complies with Part.15 of FCC Rules.
Operation is subject to the following two conditions:
1) This device may not cause harmful interference
2) This device must accept any interference received,
including interference that may cause undesired
operation.
Information
This equipment has been tested and found to comply
with the limits for a Class B digital device, pursuant to
Part 15 of the FCC Rules. These limits are designed to pro-
vide 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 communica-
tions. 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:
oReorient or relocate the equipment and/or the
receiving antenna.
oIncrease the separation between the equipment
and receiver.
oConnect the equipment into an outlet on a cir-
cuit different from that to which the receiver is
connected.
oConsult the dealer or an experienced radio/TV tech-
nician for help.
CAUTION
Changes or modifications not expressly approved by the
party responsible for compliance could void the user’s
authority to operate the equipment.

4
Model for Canada
Innovation, Science and Economic Development
Canada’s Compliance Statement:
This Class B digital apparatus complies with Canadian
ICES-003.
For European Customers
Disposal of electrical and electronic
equipment and batteries and/or
accumulators
a) All electrical/electronic equipment and waste
batteries/accumulators should be disposed of
separately from the municipal waste stream via
collection facilities designated by the government
or local authorities.
b) By disposing of electrical/electronic equipment
and waste batteries/accumulators correctly, you
will help save valuable resources and prevent any
potential negative effects on human health and the
environment.
c) Improper disposal of waste electrical/electronic
equipment and batteries/accumulators can have
serious effects on the environment and human
health because of the presence of hazardous sub-
stances in the equipment.
d) The Waste Electrical and Electronic
Equipment (WEEE) symbols, which show
wheeled bins that have been crossed out,
indicate that electrical/electronic equip-
ment and batteries/accumulators must be
collected and disposed of separately from house-
hold waste.
If a battery or accumulator contains more
than the specified values of lead (Pb),
mercury (Hg), and/or cadmium (Cd) as
defined in the Battery Directive (2006/66/
EC, 2013/56/EU), then the chemical sym-
bols for those elements will be indicated beneath
the WEEE symbol.
e) Return and collection systems are available to end
users. For more detailed information about the
disposal of old electrical/electronic equipment and
waste batteries/accumulators, please contact your
city office, waste disposal service or the shop where
you purchased the equipment.
Pb, Hg, Cd
IMPORTANT SAFETY INSTRUCTIONS (continued)
MQA and the Sound Wave Device are registered trademarks
of MQA Limited © 2016
“DSD” is a registered trademark.
The Bluetooth® word mark and logos are registered trade-
marks owned by Bluetooth SIG, Inc. and any use of such
marks by TEAC CORPORATION is under license.
Qualcomm aptX is a product of Qualcomm Technologies,
Inc. and/or its subsidiaries.
Qualcomm is a trademark of Qualcomm Incorporated,
registered in the United States and other countries. aptX is
a trademark of Qualcomm Technologies International, Ltd.,
registered in the United States and other countries.
The LHDC logo is a registered trademark of Savitech
Corporation.
Apple, Mac, OS X and macOS are trademarks of Apple Inc.,
registered in the U.S. and other countries.
Microsoft and Windows are either registered trademarks or
trademarks of Microsoft Corporation in the United States
and/or other countries.
Bulk Pet is a registered trademark of INTERFACE CO., LTD.
LDAC™ and LDAC logo are trademarks of Sony Corporation.
The terms HDMI and HDMI High-Definition Multimedia
Interface, and the HDMI Logo are trademarks or registered
trademarks of HDMI Licensing Administrator, Inc. in the
United States and other countries.
Other company names, product names and logos in this
document are the trademarks or registered trademarks of
their respective owners.
The nameplate is located on the bottom of the unit as
shown below.
Nameplate

5
Compliance of radio transmitter
and interference
This product has the function of broadband transmitter
using 2.4GHz Band.
Use frequency range: 2402MHz – 2480MHz
Maximum output power: Bluetooth® Class 2 (less than
2.5mW)
Please use only in the country where you purchased the
product.
Depending on the country, restrictions on the use of
Bluetooth wireless technology might exist.
Model for USA
Labeling of authorization
FCC ID: XEG-AI303
Model for Canada
Compliance of radio transmitter
This device contains licence-exempt transmitter(s)/receiv-
er(s) that comply with Innovation, Science and Economic
Development Canada’s licence-exempt RSS(s). Operation is
subject to the following two conditions:
1) This device may not cause interference.
2) This device must accept any interference, including
interference that may cause undesired operation of the
device.
Labeling of authorization
IC: 1559C-AI303
Model for EEA (European Economic Area)
Hereby, TEAC Corporation declares that
the radio equipment type is in compliance
with Directive 2014/53/EU., and the other
Directives, and Commission Regulations.
Model for UK
Hereby, TEAC CORPORATION declares that
the radio equipment type is in compliance
with UK Radio Equipment Regulations.
The full text of the EU and UK declaration of conformity is
available at the following internet address. Please contact
us by e-mail.
https://teacsupport.aqipa.com/
Radiation Exposure requirements
This equipment meets the regulation, which is recognized
internationally, for the case of human exposure to radio
waves generated by the transmitter.
Statement of compliance
Model for USA/Canada
This equipment complies with FCC/IC radiation exposure
limits set forth for an uncontrolled environment and meets
the FCC radio frequency (RF) Exposure Guidelines and
RSS-102 of the IC radio frequency (RF) Exposure rules. This
equipment has very low levels of RF energy that it deemed
to comply without maximum permissive exposure evalua-
tion (MPE). But it is desirable that it should be installed and
operated keeping the radiator at least 20cm or more away
from person’s body (excluding extremities: hands, wrists, feet
and ankles).
Model for EEA and UK
This equipment complies with EN 62479; Assessment of
electronic and electrical equipment related to human expo-
sure restrictions for electromagnetic fields.

6
Thank you for choosing TEAC.
Read this manual carefully to get the best performance from
this unit.
After reading it, keep it in a safe place for future reference.
Table of contents Included accessories
Check to be sure the box includes all the supplied accesso-
ries shown below.
Please contact the store where you purchased this unit if
any of these accessories are missing or have been damaged
during transportation.
Power cord × 1
Foot pads × 3
Remote control (RC-1337) × 1
Batteries for remote control (AAA) × 2
Owner’s manual (this document, including warranty) × 1
oFor information about the warranty, users living in the USA
and Canada should see pages74–75. Users living in
Europe and other regions should see page75.
Using the TEAC International Site
You can download updates for this unit from the TEAC
International Site:
https://teac.jp/int/
Click Language at the top right of the page and select the
desired country or region to access a page in the corre-
sponding language.
IMPORTANT SAFETY INSTRUCTIONS ........................2
Included accessories........................................6
Using the TEAC International Site ...........................6
Before use ..................................................7
Using the remote control ...................................7
Connections................................................8
Connecting speakers ..................................... 10
Main unit parts and functions............................. 11
Remote control parts and functions. . . . . . . . . . . . . . . . . . . . . . . 12
Basic operation ........................................... 13
MQA (Master Quality Authenticated)...................... 14
Crossfeed function ....................................... 14
HDMI (eARC) ............................................. 14
Bluetooth® wireless technology........................... 15
Energy-saving functions .................................. 18
Playing back music on a computer........................ 19
Playback operations ...................................... 22
Troubleshooting.......................................... 24
Specifications............................................. 25

7
Using the remote control
Precautions for use
VMisuse of batteries could cause
them to rupture or leak, which
might result in fire, injury or the
staining of nearby materials.
Please carefully read and observe
the precautions on page3.
oWhen using the remote control, point it toward the
remote control signal receiver on the main unit from a
distance of 5m (16ft) or less. Do not place obstructions
between the main unit and the remote control.
oWhen not using the remote control for an extended
period of time, remove the batteries to prevent leakage.
Installing batteries
Remove the cover from the back of the remote control and
insert two AAA batteries with their ¥/^oriented as shown
in the case. Replace the cover.
When to replace batteries
If the distance required between the remote and the main
unit decreases or if the unit stops responding to the remote
buttons, replace both batteries with new ones.
Dispose of the used batteries according to the instructions
on them or requirements set by your local municipality.
VPlacement precautions
oDo not install this unit in a location that could become
hot. This includes places that are exposed to direct
sunlight or near a radiator, heater, stove or other heat-
ing equipment. Moreover, do not place it on top of
an amplifier or other equipment that generates heat.
Doing so could cause discoloration, deformation or
malfunction.
oYou may stack this unit with a PD-301 or UD-301.
However, place this unit on top in order to improve heat
dissipation.
oWhen installing this unit, leave a little space (at least
5cm or 2") between it and walls and other devices in
order to allow good heat dissipation.
If you put it in a rack, for example, leave at least 5cm (2")
open above and 10cm (4") open behind it.
Failure to provide these gaps could cause heat to build
up inside and result in fire.
Maintenance
Wipe dirt from the top cover and other panel surfaces using
a soft cloth that has been slightly dampened with a diluted
neutral cleanser.
Do not wipe with chemical cleaning cloths, thinner or other
chemical agents. Doing so could damage the surface.
VFor your safety, disconnect the power cord
from the outlet before cleaning.
Before use

8
VComplete all other connections before turning the unit on
oCarefully read the manuals of the devices that you are connecting and follow their instructions when making
connections.
oDo not bundle connecting cables with power cords. Doing so could cause noise.
oConnect all plugs completely.
Connections
LR
E
DF
C
A B
Line input
connector
Subwoofer
Digital audio output
device
Digital audio output
device
DIGITAL OUT
(OPTICAL)
DIGITAL OUT
(COAXIAL)
c
Cassette deck, CD player, etc.
Audio output
(LINE OUT, etc.)
Computer
RCA cables
USB cable
Optical digital cable
RCA coaxial digital cable
Included power cord
Install the dedicated
driver on the computer
before connecting this
unit to it (page19).
RCA cable
HDMI cable
TV that supports
eARC or ARC
Wall outlet

9
A Analog audio input (LINE 1, LINE 2)
connectors
Use these to input 2-channel analog audio signals.
Connect an audio output device such as a cassette
deck or CD player to these connectors using commer-
cially-available RCA cables.
Connect this unit’s R input connector to the R output
connector of the audio output device, and this unit’s
L input connector to the L output connector of the
other device.
White (L)
Red (R)
White (L)
Red (R)
B USB input port
Use this to input digital audio from a computer.
Connect it to a computer’s USB port.
Use a commercially-available USB cable.
oInstall the dedicated driver on the computer
before connecting this unit to it (page19).
C Power inlet (~IN)
Connect the supplied power cord here.
After all other connections are complete, connect the
power cord’s plug to a wall outlet.
VDo not use any power cord other than the
one included with this unit. Use of other
power cords could result in fire or electric
shock.
VDisconnect the power plug from the outlet
if you will not use the unit for a long time.
D DIGITAL IN (COAXIAL, OPTICAL) audio
input connectors
Use these to input digital audio. Connect digital audio
output connectors of digital audio devices here.
COAXIAL: RCA digital coaxial cable
OPTICAL: Optical digital cable (TOS)
E SUBWOOFER OUT connector
If you want to use a subwoofer, connect it to this
connector.
oThe VOLUME knob on the unit front controls the
output level.
F HDMI (eARC) audio input connector

10
Connecting speakers
VPrecautions when making connections
oAfter all other connections are complete, connect the
power cord’s plug to a wall outlet.
oCarefully read the manuals of the devices that you are
connecting and follow their instructions when making
connections.
ATTENTION
oCheck the impedance of your speakers. Connect speakers
with an impedance of between 4Ω and 8Ω. If speakers
with different impedance ratings are used, the protection
circuit could operate, causing sound output to stop.
oThe red speaker terminals are positive (+) and the black
speaker terminals are negative (–). Generally, the + wire
of the speaker cable is marked to distinguish it from the
– wire of the cable. Connect the marked wire to the red +
terminal and the unmarked wire to the black – terminal.
oIf the exposed core wires at the tips of the speaker
cables should touch other cables or terminals, an electri-
cal short might occur.
Never allow speaker cables to cause a short.
oTo prevent hum and noise, avoid bundling the cables
together with the AC power cord or other cables.
How to connect speakers
1 Turn the terminal cap counterclockwise to
loosen it.
oThe speaker terminal caps cannot be fully removed
from the unit.
2 Insert the wire into the hole in the terminal
post and turn the terminal cap clockwise to
securely connect it.
oMake sure none of the wire insulation is under the
terminal and only the bare, stripped wire is touch-
ing the terminal.
3 Conrm that the cable is fastened securely
by gently pulling the cable.
Connecting with banana plugs
You can also make connections using commercially-avail-
able banana plugs. First, connect the banana plugs to the
speaker cables and then connect the plugs to the terminals.
oKeep the caps tightened when in use.
oCarefully read the instructions for the banana plugs that
you are using.
Notice about the European model
In accordance with European safety regulations,
connecting banana plugs to speaker terminals
is not allowed on European models.
The holes into which banana plugs could be
inserted have been covered with black caps.
Connect speakers using bare wires or spade lugs.
If a black cap should become separated from its
terminal, return it to its original position.

11
Main unit parts and functions
A Standby/on (¤) button
Press this to turn the unit on and put it in standby.
When the unit is turned on, the ring around the but-
ton lights blue.
oWhen this unit is in standby mode, it consumes
standby power. For this reason, we use the term
“standby”rather than “off”.
B PHONES jack
Connect a 3.5mm (1/8") stereo mini plug for head-
phones here.
oThis headphone amp circuit uses a four-pole
connector with independent left and right for
grounding. Ordinary plugs with 3 or 4poles can
be used.
oIf headphones are connected here, audio will not
be output from the speaker (SPEAKERS) terminals
or SUBWOOFER OUT connector on the back of
the unit.
Wiring illustration
L+ R+ L− R−
C SOURCE button
Use this button to select the input source.
D Input source indicators
The indicator for the source that is selected lights.
These indicators blink when an input signal is not
input properly.
This unit can play back linear PCM signals. It cannot
play back Dolby Digital, DTS, AAC and other formats.
Set the source device to linear PCM output.
E Remote control signal receiver
This receives signals from the remote control. When
operating the remote control, point it at the remote
control signal receiver.
F CROSSFEED knob
Turning this right will increase the amount that the left
and right sound signals are each mixed into the other
channel, making the overall sound more centralized in
the stereo field. Turning this all the way to the right will
make the sound mono. Turning this all the way to the
left will turn this function off (page14).
G VOLUME knob
Use this to adjust the volume. Turn it right to increase
and left to decrease the volume.

12
a MUTE button
Press this to mute the sound temporarily. To restore the sound,
press it again.
b Standby/on (¤) button
Press this to turn the unit on and put it in standby.
c Input source selection buttons
Use these to select the playback source.
d VOLUME (−/+) buttons
Use these to adjust the volume.
e UPCONVERT button
Press this to change the upconversion setting (page22).
f FILTER button
This changes the digital filter type (page22).
g DISPLAY button
This shows the playback sampling frequency (Fs) (page22).
Remote control parts and functions
You can control both this AI-303 and a PD-301
using the RC-1337 remote control.
Only the buttons used for the AI-303 are
explained in this document.

13
Basic operation
1 Press the standby/on (¤) button to turn the unit on.
2 Press the SOURCE button to select the input source.
Each time the SOURCE button is pressed, the source changes as
follows:
USB
HDMI (ARC) LINE 2
Bluetooth LINE 1
COAXIAL OPTICAL
The indicator lights for the selected source.
oThe input source indicators blink when the input signal is a digital audio format (such as Dolby Digital, DTS or
AAC).
If this is the case, check to see if the connected digital audio output device has a “PCM” setting for the digital
output format. Refer to the operation manual for that device to make this setting.
oWhen using this unit with a Windows computer, before setting this unit to USB and playing back audio files on
the computer, you must install the dedicated driver on that computer (page19).
3 Operate the audio output device.
Refer to the operation manual of the audio output device that you
are using.
4 Adjust the volume.
Turn the VOLUME knob or use the VOLUME buttons on the remote
control to adjust the volume to the appropriate level.

14
MQA is an award-winning British technology that delivers
the sound of the original master recording. The master MQA
file is fully authenticated and is small enough to stream or
download.
Visit mqa.co.uk for more information.
The AI-303 includes MQA technology, which enables you to
play back MQA audio files and streams, delivering the sound
of the original master recording.
The state of the MQA indicator shows whether the unit is
decoding and playing an MQA stream or file, guaranteeing
that the sound is identical to that of the source material.
When the MQA indicator lights blue, this shows that the file
playing is an MQA studio file that has either been approved
in the studio by the artist/producer or has been verified by
the copyright owner.
oThis unit can decode MQA streams and files only when
the playback source is USB, HDMI (ARC), COAXIAL or
OPTICAL.
Indicator during MQA playback
Type MQA indicator
MQA Green
MQA Studio Blue
MQA Core Magenta
MQA (Master Quality Authenticated)
oBy using the crossfeed function when listening through
headphones, a sound that is closer to the sound heard
from speakers can be re-created. In particular, this can
improve appreciation of music recorded with extreme
left and right channel separation, which was common in
the early days of stereo recording, as well as when listen-
ing for extended periods.
oWhen using speakers, the sound image will be focused
toward the center of the stereo field. This has the effect
of making vocals and narration clearer and easier to
understand.
oTurn the CROSSFEED knob all the way to the left to turn
off the crossfeed function and use ordinary stereo play-
back. Turning this all the way to the right will focus all
the sound to the center and make it mono.
HDMI (eARC)
By using a single HDMI cable to connect the HDMI connec-
tor of this unit to the ARC connector of a TV that supports
ARC (Audio Return Channel) or eARC (Enhanced Audio
Return Channel), digital audio (up to 192kHz/24-bit) from
the TV or player connected to the TV can be output from the
speaker and headphone jacks of the AI-303.
Since HDMI CEC is supported, the TV remote control can be
used to adjust the volume of this unit and mute it. In addi-
tion, the power of this unit can be linked to turning the TV
power on/off (standby).
oHDMI CEC support commands differ according to the TV,
so synchronized operation with all TVs is not guaranteed.
oThis unit complies with the eARC (Enhanced Audio
Return Channel) specification, but it does not support
the decoding of Dolby Atmos®, Dolby TrueHD, DTS:X™,
DTS-HD and other formats. Set the audio output of the
TV to linear PCM before connecting.
oThe digital audio signals that can be output varies by
TV. Even if a Blu-Ray Player or other playback device out-
puts high-resolution audio signals, the TV might restrict
resolution to 48kHz/16-bit. For details, check with the
manufacturer of the TV that you are using.
Crossfeed function

15
Bluetooth® wireless technology
Bluetooth® notes
When using this unit with a mobile phone or other Bluetooth
devices, they should be no more than about 10m (33ft)
apart.
Depending on the circumstances of use, however, the effec-
tive transmission distance might be shorter.
Wireless communication with every device that supports
Bluetooth wireless technology is not guaranteed.
To determine the compatibility between this unit and
another device that supports Bluetooth wireless technology,
refer to that device’s operation manual or contact the shop
where you purchased it.
Content protection
This unit supports SCMS-T as a form of content protection
when transmitting audio, so it can play protected audio.
Transmission security
This unit supports security functions during Bluetooth wire-
less transmission in accordance with the Bluetooth standard
specifications, but it does not guarantee the privacy of such
transmissions.
TEAC CORPORATION will bear no responsibility should an
information leak occur during Bluetooth wireless transmission.
Profiles
This unit supports the following Bluetooth profiles.
oA2DP (Advanced Audio Distribution Profile)
oAVRCP (Audio/Video Remote Control Profile)
In order to transfer audio using Bluetooth wireless transmis-
sion, the Bluetooth device must support A2DP.
In order to control playback on the Bluetooth device, it must
support AVRCP.
Even if a Bluetooth device supports the same profiles, though,
its functions might differ according to its specifications.
Codecs
This unit supports the following codecs. It will automatically
select one that is appropriate for the other Bluetooth device
during audio transfer.
oLDAC
oLHDC
oQualcomm® aptX™ HD audio
oQualcomm® aptX™ audio
oAAC
oSBC

16
1 Press the standby/on (¤) button to turn the unit on.
2 Press the SOURCE button one or more times to select
Bluetooth ( ).
This puts the unit into Bluetooth mode.
3 Pair or connect with another Bluetooth device.
Pairing with another Bluetooth device
The first time another Bluetooth device is used with this unit, they
must be paired.
To prepare this unit to pair, put it into Bluetooth mode and press
the SOURCE button or remote control button for at least three
seconds. When this unit is ready to pair, its indicator flashes rapidly.
After this unit enters pairing mode, pair with it (shown as AI-303) on
the other Bluetooth device. The indicator stops flashing and stays lit
when pairing completes and they are connected.
For details, refer to the operation manual of that Bluetooth device.
To connect with a Bluetooth device that has already been paired,
follow the connection procedures for that device.
oWhen pairing or connecting, devices should be within a few
meters of each other. If they are too far apart, pairing and con-
nection afterwards might become impossible.
oIf you want to delete pairing data and initialize the Bluetooth cir-
cuit, press the SOURCE button or remote control button for at
least 10 seconds. At this time, all input indicators will flash twice.
VATTENTION
Regardless of the connection standby states of this unit and the
other Bluetooth device, if the Bluetooth indicator continues blinking
for a long time, turn off both this unit and the other device. Then,
restart them and conduct connection procedures again.
Bluetooth®wireless technology (continued)

17
4 Start audio output on the other Bluetooth device.
oConfirm that the volume is turned up on the other Bluetooth
device. If the volume of the audio being output is not turned up,
no sound might be output from this unit.
5 Adjust the volume.
oThe volumes of this unit and the other Bluetooth device are
not linked. This unit cannot control the volume of the other
Bluetooth device, and that device cannot control the volume of
this unit.
NOTE
oYou cannot select the codec to be used by pressing a button, for
example.
oDue to the characteristics of Bluetooth wireless technology, compared
to the playback on the Bluetooth device, audio output through this
unit will be slightly delayed.
Checking the Bluetooth audio codec
The audio codec being used for Bluetooth playback is shown by the green
indicator.
Support for multipoint connection
Connecting with 2 Bluetooth devices at the same time is possible. Audio
can only be output from one at a time when connected. Output from the
device that most recently started playback will be prioritized. Playback will
be stopped on the previously playing device.
LDAC is an audio coding technology developed by Sony that enables the transmission of High-Resolution
(Hi-Res) Audio content, even over a Bluetooth connection.
Unlike other Bluetooth compatible coding technologies such as SBC, it operates without any down-con-
version of the Hi-Res Audio content*, and allows approximately three times more data** than those other
technologies to be transmitted over a Bluetooth wireless network with unprecedented sound quality, by
means of efficient coding and optimized packetization.
* excluding DSD format contents
** in comparison with SBC (Subband Coding) when the bitrate of 990kbps (96/48 kHz) or 909kbps
(88.2/44.1kHz) is selected

18
This product has energy-saving sleep and standby states.
The operation of these functions depend on the automatic standby setting
and the selected input source.
Sleep overview
Only when the input source is USB, HDMI (ARC), Bluetooth, COAXIAL
or OPTICAL
If there is no digital input signal from the selected source and no operation
occurs for about three minutes, the unit will enter sleep mode.
Inputting the selected digital signal will wake the unit (automatic power
on function).
oWhen in sleep mode, the input indicators will light dimly.
When the automatic standby function is on
The unit will enter standby mode after about 30 minutes if it remains in
sleep mode or if there is no sound when the input source is LINE. When in
standby mode, inputting the selected digital signal will not turn the unit
on again.
Press the standby/on (¤) button on the main unit or the remote control
to turn the unit on again.
oPower consumption in standby mode is 0.5W or less.
Checking procedure
If the automatic standby function is off, all the input indicators will light
temporarily when the unit is turned on.
Setting the automatic standby function
When the unit is in a standby state, press and hold the standby/on (¤)
button. After about three seconds the input indicators will change as
shown below and the automatic standby setting will change.
From all lit to two flashes: automatic standby function on
From the current input indicator lit to all indicators lit: automatic standby
function off Press and hold
Energy-saving functions

19
Playing back music on a computer
Operating systems that have been
confirmed for use
We provide information about operating systems that have
been confirmed for use on the product web page at the
following URL.
https://teac.jp/int/product/ai-303/
Installing the driver
When using Mac
This unit can be operated with the standard OS driver, so
there is no need to install a driver.
A dedicated driver must be installed on the computer, how-
ever, to use Bulk Pet.
When using Windows
The dedicated driver must be installed on the computer.
Installing the driver on a computer
Install the dedicated driver on the computer after download-
ing it from the following URL.
For details about installation and OS setting procedures, see
the installation guide included with the driver.
https://teac.jp/int/product/ai-303/download
The sampling frequencies that can be transmitted are 44.1kHz,
48kHz, 88.2 kHz, 96kHz, 176.4kHz, 192 kHz, 352.8kHz and
384kHz.
2.8MHz, 5.6MHz and 11.2MHz DSD are also supported.
When properly connected, you will be able to select “TEAC
USB AUDIO DEVICE” as the audio output for the operating
system.
Downloading playback application
TEAC HR Audio Player
You can download Mac and Windows versions of our free
TEAC HR Audio Player application that supports playback of
DSD files.
https://teac.jp/int/product/ai-303/download

20
Playing back audio files on a computer
1 Connect this unit to the computer using a USB cable.
oWhen a dedicated driver is necessary for connection, it must be
installed on the computer beforehand (page19).
oUse a cable that has a USB Type-C connector for connecting to this
unit.
2 Turn the computer on.
oConfirm that the computer has started up correctly.
3 Press the standby/on (¤) button to turn the unit on.
4 Press the SOURCE button repeatedly to select USB.
5 Start playback of an audio le on the computer.
If you can adjust the volume from the computer, set it to its maxi-
mum level and use this unit’s VOLUME knob to adjust the level for
the best audio quality.
oIf you are using the TEAC HR Audio Player application, the vol-
ume cannot be adjusted from the computer.
USB cable
Playing back music on a computer (continued)