Class-D Power Amplifier: In order to deliver high-quality audio
performance, the TEAC AI-503 incorporates a well-regarded, high-output power
amplifier made by ICEpower a/s. This guarantees high-resolution playback of
delicate signals as well as excellent linearity at higher output levels. The use
of a compact, high-efficiency Class-D power amplifier enables the inclusion of a
dual-mono circuit configuration in the DACs (highly beneficial to digital audio)
while retaining a small, stylish form-factor.
- 8Ω Rating: 30 watts x 2
- 4Ω Rating: 60 watts x 2
High-Capacity Toroidal-Core Power Transformers: Power is supplied by
efficient toroidal-core power transformers specifically designed to suppress
magnetic flux leakage and prevent electromagnetically-induced noise, providing
clean and stable current at all times.
High-Performance VERITA AK4490 DACs: The TEAC AI-503 utilizes
high-performance VERITA AK4490 DACs, made by Asahi Kasei Microdevices
Corporation. Along with native playback of 11.2MHz DSD signals through direct
processing, a wide range of high-resolution audio sources (including
384kHz/32-bit PCM digital input) are supported. These DACs enable the
reproduction of the finely etched detail and outstanding sense of stereo
placement that are the hallmarks of quality high-definition high-resolution
audio sources. The AK4490 is a member of the Asahi Kasei Microdevices
Corporation Audio4pro family brand of products developed for professional audio
devices and high-end digital audio applications.
Dual-Mono Configuration: As well as helping deliver class-leading
levels of power, the sophisticated dual-mono configuration also extends to the
DAC and the preamp. The dual-mono layout incorporates two completely independent
mono circuits for the left and right channels. Starting with the
high-performance VERITA AK4490 DACs, this arrangement provides outstanding
isolation between the two channels. The suppression of interference between the
left and right channels is particularly important when it comes to headphone
TEAC-QVCS High-Precision Volume Control Circuit: For the preamp
circuit, the AI-503 employs the TEAC-QVCS (Quad Volume Control System), an
ingenious circuit with a fully-balanced design. It allows balanced processing of
the audio signal at every stage, from immediately after digital-to-analog
conversion until the signal reaches the volume amplifier. Control signals,
transmitted from the volume knob, simultaneously adjust the variable-gain
amplifier-type volume controls of four independent circuits - providing a
positive and negative for both the left and right channels. Using this system,
the unnecessary manipulation of audio signals is eliminated, and the left/right
and positive/negative independence of the audio signals is preserved until a
point immediately before the power amplifier, achieving a clear sound quality
with outstanding channel separation (this process only applies to the balanced analog
inputs). What's more, "gang errors" (level discrepancies between left and right
channels at low volumes), which can be a particular issue during headphone
listening, have been completely eliminated, so you can enjoy accurate audio even
when using low-impedance in-ear monitors.
Asynchronous USB w/ Built-in 44.1kHz & 48kHz Clocks: The AI-503 supports
asynchronous transfer mode when connected by USB, allowing it to control PCM and
DSD signals by synchronizing them with its own clock (generated by a
high-precision crystal oscillator) rather than synchronizing with a computer
clock signal that is invariably unstable and noisy. Two dedicated internal
clocks (running at 44.1kHz and 48kHz) are built-in. By clocking signals that are
a multiple of the clock frequencies to an audio-grade, high-precision crystal
oscillator, featuring inherently low phase noise, the damaging effects of jitter
on audio quality can be largely suppressed and the audio source can be
reproduced more faithfully.
Discrete, Push-Pull Headphone Amp: The dedicated headphone amp employs
Class AB operation, as well as a discrete push-pull circuit and op amp. TEAC has
applied all the expertise we gained during the development of the UD-503 to give
this model a circuit design that suppresses noise while maintaining the wide
operational range of a Class-A amplifier. The fine details and nuances of your
music, as captured in high-resolution audio, are delivered naturally. The AI-503
headphone circuit design also features completely separated grounding for left
and right channels from the amp to the final 4-pole jack. By completely
separating the grounding of the left and right channels from the amplifier,
channel separation is greatly increased and a much more transparent soundstage
achieved. In addition, the headphone amp output features a 2-stage
gain-switching function which enables optimal volume setting when listening
through anything from low-impedance in-ear monitors to high-impedance 600Ω
Note: Earphones and headphones with 3-pole plugs can also be used, but to
benefit from separate left/right ground drive, you should use earphones or
headphones with 4-pole plugs.
All Metal Chassis: Since the enclosure is completely made of metal
panel-work, which is resistant to external noise, the infiltration of
electromagnetic noise generated by computers and other equipment is
well-suppressed. This creates an electrically "clean" internal environment with
little noise, even in outside environments that offer difficult conditions for
audio equipment. The metal chassis also has 8mm-thick aluminum panels on both
ends. These features prevent twisting and bending, resulting in a strong and
stable body structure. In addition, its compact footprint, allows it to be
placed on tables, sideboards and in other small spaces.
Asynchronous USB-B 2.0 Input: The TEAC AI-503 is equipped with a
rear-panel Asynchronous USB-B 2.0 port for connection to your Windows PC or Mac computer,
TEAC HR Audio Player software. Through the use of its USB-B input and the TEAC
HR Audio Player, the AI-503 supports resolutions up to 11.2MHz DSD and
384kHz/32-bit PCM (plus other formats like 24-bit/192kHz FLAC). In addition,
"DSD native playback" (in which DSD is converted directly to analog without
first being converted to PCM) is also supported.
Bluetooth Audio Streaming: The TEAC AI-503 features built-in
Bluetooth A2DP/AVRCP with support for wireless audio streaming from your
Bluetooth-enabled smartphone (including iPhone & Android), tablet (including
iPad & Android), or computer (including Windows or Mac), or laptop. The AI-503's
onboard Bluetooth receiver supports LDAC and aptX, as well as AAC, in addition
to Bluetooth's standard SBC codec. You can also control basic playback
functions, like Play/Pause & Previous/Next Track. from the included remote
control. There is no song/artist/album info display.
- LDAC: LDAC is an audio coding technology developed by Sony that
enables the transmission of High-Resolution (Hi-Res) Audio content
(excluding DSD), even over a Bluetooth connection. Unlike other Bluetooth
compatible coding technologies such as SBC, it operates without any
down-conversion of the Hi-Res Audio content, and allows approximately 3x
more data than those other codecs to be transmitted over a Bluetooth
wireless connection with unprecedented sound quality.
- aptX: aptX is an audio coding technology by Qualcomm which
enables stereo "CD-like" audio quality (48kHz/16-bit LPCM) over a Bluetooth
wireless connection. Many Bluetooth-enabled Android smartphones & tablets
Note: This unit will only pair & connect to one device at a time.
Optical & Coaxial Digital Inputs: The AI-503 is outfitted
with one optical (toslink) input and one coaxial (RCA) digital input for
connection of other digital audio sources like your CD/SACD, Blu-ray/DVD player,
or network player. These digital inputs will accept two channel linear PCM (not
Dolby Digital/DTS). The coaxial digital input supports 32, 44.1, 48, 88.2, 96,
176.4, and 192kHz sampling frequencies (16- or 24-bit). The optical digital
inputs support only 32, 44.1, 48, 88.2, and 96kHz sampling frequencies (16-or
24-bit). Both digital inputs also support 2.8MHz DSD audio files.
Front-Panel Combo Jack: The TEAC AI-503 has a front-panel 3.5mm jack
which can be used as an analog or digital input. This front-panel input jack is
a convenient way of connecting digital audio players with optical digital and
analog outputs. It will accept an analog stereo minijack cable or mini-toslink
cable (both sold separately). The unit will automatically switch to analog or
digital according to the type of plug connected.
Analog Input: In addition, the unit has a rear-panel stereo
analog RCA input, so you can also connect an analog turntable with a built-in phono EQ amplifier, a
cassette deck, or other piece of analog equipment (all sold separately).
Binding-Post Speaker Terminals: The TEAC AI-503 is equipped
with four binding-post speaker terminals to connect a pair of loudspeakers (4-8Ω).
The binding-post speaker terminals will accept bare wire (up to 8AWG),
spade-connectors, pin-connectors, and banana plugs (single only).
Analog Pre-Out: Thanks to its analog stereo pre-outs, the AI-503 can also be used as a high-quality
preamp. As the volume from the RCA pre-out jacks can be varied, you can achieve an upgraded audio system simply by connecting a power amplifier.
3.5mm Headphone Output: The TEAC AI-503 is equipped with a front-panel
3.5mm (4-pole) headphone jack with a maximum output of 280mW + 280mW and support
for 16-600Ω headphones. When headphones are
connected, audio will not output from the unit's speaker terminals or preamp
outputs. 3-pole & 4-pole headphone cables can be used
HR Audio Player App (for Windows & Mac): The
TEAC HR Audio Player is a free music playback software which allows
connection of the AI-503 to your computer via USB for native playback of 11.2MHz
DSD, 384kHz PCM and other high-resolution music files (including 24-bit/192kHz
FLAC). TEAC HR Audio Player even supports ASIO 2.1 and DoP (DSD over PCM) formats, allowing native
playback of 11.2MHz DSD audio sources on Windows PC and Mac computers. The TEAC HR Audio Player may be installed on a Windows (7 and above) PC
or Mac (OS X 10.7 and above) computer. When using this software with a Windows
computer, you must install a dedicated driver on that computer before connecting
the AI-503 via USB.
Digital Filters: Filter types include 4 PCM and an "Off" mode , as
well as 2 DSD digital filters. You can use the remote control to set the optimal
filter, according to the input file format and type of music. You can also
change the filter during music playback so that you can fine-tune the audio
- PCM Filters: FIR Sharp (steep roll-off used to sharply cut
signals outside the audio band), FIR Slow (slow roll-off used to gently cut
signals outside the audio band), SDLY Sharp (short delay with steep roll-off
used to sharply cut signals outside the audio band), or SDLY Slow (short
delay with slow roll-off, used to gently cut signals outside the audio band)
- DSD Filters: Cutoff Frequency of 50kHz or Cutoff
Frequency of 150kHz
Note: When receiving signals at 352.8kHz or 384kHz, the digital filter
will be disabled during playback regardless of this setting.
Aluminum Volume Knob & IR Remote: TEAC pays great attention to each
and every control, including an aluminum volume knob with firm torque and an
aluminum alloy topped IR remote. The remote offers Power, Volume, Mute, Input,
Filter, Upconvert, Menu, and Playback controls.
Dimmable VU Meters: Providing a visual indicator of system gain,
analog level meters are built into the front of the unit. These meters provide a
stylish insight into operating levels of the system and feature a dimmer
function which can be set to one of four levels (bright, normal, dim, off),
allowing you to adjust the brightness to match the lighting of the room, you can
also turn off the operation of the level meters completely.
Auto Power Down: If there is no signal from the selected
input source and no operation has occurred for approximately 30 minutes, the
AI-503 will enter standby mode. Power consumption in standby mode is 0.2W or