TEAC - AI-303 USB DAC Amplifier

The only connection between the AI-303 and a TV is an HDMI cable. Supporting ARC/eARC and HDMI CEC, volume control and power on/off of the AI-303 can be controlled from a TV remote, while receiving PCM 192/24 Hi-Res audio as long as the TV supports the resolution. Thanks to its small footprint, installing the AI-303 on a TV cabinet is possible.
* Please set the digital output to "PCM" in the output settings of the TV.

In order to maximize studio master quality sound quality of the digital source, the D/A converter on the AI-303 equips two types of digital filters and x2Fs, x4Fs, and x8Fs up-conversion processing to pursue your preferred sound.

Connections with the digital sources are up-to-dated. The AI-303 equips an HDMI for TV, a USB-C for PC/Laptop and Coaxial/Optical for conventional digital music players, maximizing potential of each digital source with the high performance D/A converter.

The Bluetooth® receiver is employed for easy wireless connection with a smartphone, supporting high-resolution wireless codecs including LDAC^®, LHDC, and Qualcomm^® aptX^™ HD, in addition to other standard Bluetooth^® codecs such as Qualcomm^® aptX^™, AAC, and SBC. The LEDs on the front panel indicate which codec is engaged when connection is established.

The AI-303 also supports wide variety of digital devices such as smartphone/tablet and portable digital audio player that support USB Audio 2.0, via a self-powered USB-C port allowing auto device detect when the device equips a USB-C. Most Android devices and recent iPad Air/iPad Pro that equip USB-C port allow single USB-C cable connection without extra devices.
*1 An additional USB Camera Adapter from Apple is required when connecting to an iPhone.
*2 When connecting to an Android device, "OTG Connection" must be turned on or "USB Debug" must be turned on from the developer option menu.

A two pairs of LINE inputs even fits your existing audio system including CD players and analog turntables.
* Analog turntable must be equip a built-in Phono amplifier.

The compact AI-303 accommodates a high energy efficient and high performance Ncore^® power amplifier designed by Hypex, borrowed from upper model, delivering clear and crisp sound with rich musicality.

The headphone amplifier circuit is designed as separated ground on both Left and Right channels from the pre-amplilfier section to headphone jack which is 4-pole type. By separating the both grounds, the channel separation is significantly improved while realizing clear sound stage.
*1 Ground-separate connection is available with Headphones with a 4-pole plug.
*2 Headphones with a conventional 3-pole plug is also compatible.
*3 Pin assignment of the 4-pole jack: Tip: L+, Ring: R+, Ring: L–, Sleeve: R–

The headphone amplifier employs the Coupling Capacitor Less Circuit (CCLC) design, which eliminates these negative effects caused by capacitors and provides a high-dimensional headphone listening environment with sufficient low-frequency range and good response, while conventional headphone amplifier design that employs output stage coupling (or removal of DC signal) inevitably affects the sound due to capacitors, such as sound changes, phase delays, and low-frequency level drops.

The Crossfeed function provides natural sense of sound source deployment on Headphone listening, while emphasizing presence of the center source to improve lack of center sound and clarifies human voice range such vocal, narration and dialogues. The Crossfeed effect is adjustable with the CROSSFEED knob on the front panel.

The AI-303 supports MQA full decoding to enjoy studio master quality sound, from any digital inputs USB-C, HDMI, Coaxial and Optical inputs from MQA streaming and MQA CD from CD player via digital connection.

The AI-303 equips a dedicated SoC for digital processing, and various digital processes including MQA decoding are performed on the SoC. For studio master quality sound, the digital filters required for analog conversion are also processed in the SoC instead of in the D/A converter.
In addition to an FIR filter with short delay and slow roll-off characteristics, an RDOT filter with natural timbre and sound field reproducibility based on analogy completion technology using fluency theory is available for the digital filter, which can be said to be the key to tone.
In combination with up-conversion, subtle differences in sound nuance varies by type of filters are realized.
Furthermore, when the RDOT filter is selected with the up-converter turned off, the D/A converter operates as a NOS (Non Over Sampling) D/A converter. in NOS mode, pre-echo and post-echo due to impulse response are suppressed and fluctuations in the time axis direction are eliminated, enabling faithful analog conversion to the input waveform. This enables analog conversion with high fidelity to the input waveform.

Unlike conventional volume circuit, the front volume circuit of the AI-303 is designed not to pass the music signal directly.
By reading the value of the volume knob, the circuit reproduces the value with a resistive ladder type attenuator on the circuit board, thereby transmitting the music signal to the amplifier in the shortest path and maintaining the purity of the signal.
The system also achieves low distortion and high S/N even when the volume is attenuated, so that the original clear sound of the sound source is delivered even at low volume levels without loss of sound quality.
In the last, but least, the level difference of the Left and Right channels (gang error) and crosstalk between both channels are minimized.

When used as a USB DAC, the AI-303 operates in asynchronous mode, where the input signal timing is regulated by the on-board clock, the connection with PC/Laptop and the AI-303 realizes purer digital signal transmission without affecting USB transmission jitters.

When sending a huge amount of digital data of high-resolution sound sources through a USB cable, the conventional transmission method causes a large uneven processing load on both the sending PC and the receiving USB DAC, which may result in problems such as sound interruption. However, "Bulk Pet" realizes stable data transfer by averaging the processing load on both sides to transfer a certain amount of data consistently. Since the sound quality also changes as the load status of the PC changes, you are able to select your preferred sound quality from four pre-set transfer modes.

TEAC’s unique three-point support foot "Stress-less Foot" is employed to enable stable installation without being affected by even the slightest distortion of the floor surface. Unlike conventional foot, the Stress-less foot is designed not to fix to the chassis directly, allowing it to vibrate freely to achieve a more natural sound.
The foot, made of machined steel, is not firmly fixed, but is mounted hanging from the bottom, enabling a more natural and rich sound with a sense of sound source deployment similar to that of a conventional pinpoint spike foot.

The built-in Bluetooth^® receiver engages connections with two difference devices at the same time. For example, when playing songs from a smartphone, the AI-303 can switch to another just like input source select without having annoying reconnection steps.
* Simultaneous playback is not supported.

Spec description