iBasso D17 Atheris Portable DAC and Headphone Amplifier

R2R + 1-Bit Dual Structures

The D17 utilizes iBasso's in-house developed discrete R2R and 1-bit DAC. It features a four-channel, fully balanced symmetrical R2R discrete component DAC, utilizing a total of 284 high-precision film resistors with an accuracy of 0.01%.

The R2R decoding provides a natural, delicate sound with a natural analog presentation, offering a unique lively listening experience. The in-house developed 1-bit DAC employs 8 sets of 8E, totaling 64 PWM-DACs, delivering a landscape of rich musical details and extremely high-resolution audio playback.

Three Selectable DAC Modes

• NOS mode: PCM utilizes the R2R DAC for decoding, while DSD utilizes 1-bit DAC decoding
• OS mode: this mode sends all decoding duties to the R2R DAC and sends all audio to PCM format
• SD mode: this mode sends all decoding to 1-bit DAC structure and converts all audio to DSD format

284 High-Precision Resistors

The D17 adopts a four-channel fully balanced symmetrical R2R architecture with 284 meticulously selected ultra-precise film resistors with a tolerance of one ten-thousandth. Equipped with in-house developed hardware resistor compensation circuitry and software compensation algorithms, the D17 achieves a THD+N of -104 dB in R2R mode, outperforming mainstream R2R devices by over ten decibels and competes with various flagship R2R desktop DACs. R2R decoding offers a rich analog voicing, producing a warm, delicate sound with exceptional musicality.

1-Bit Architecture

In 1-bit mode, the four channels L+, L-, R+, and R- each have 16E, totaling 64 PWM-DAC units working together. This is controlled by the FPGA-Master 3.0 with nanosecond-level precise I/O delay management while compensating for wiring delay to ensure that the signal edges arriving at the DAC are aligned and strictly synchronized. This not only achieves an impressive THD+N of -114 dB but also significantly enhances sound detail and density.

FPGA-Master 3.0 Inside

The D17 is equipped with iBasso's in-house developed FPGA-Master 3.0 architecture, deeply integrated with two Accusilicon ultralow-phase noise femtosecond oscillators to create a pure, unified single-clock source. Through nanosecond-level, high-precision delay control and real-time clock regeneration technology, the system can simultaneously compensate for R2R decoding and 1-bit decoding, reducing clock jitter and distortion to extremely low levels. This ultimately delivers highly accurate sound reproduction, ensuring that every detail is presented in its original form.

Fully Balanced Headphone Amp with Incredible Power

The two Nutube 6P1 tubes on the D17 impart a unique tube character and a warm, mellow yet dynamic texture to the sound. The anode is powered by a 24V high-voltage supply, providing better linearity. Paired with the high-performance TI buffer amplifier BUF634A, it ensures a steady and powerful source of power. As a result, the D17 can deliver over 1200mW per side at 32 ohms, easily driving a wide range of flagship IEMs and high-impedance headphones.

Secondary Reduction of Microphonic Effect

The D17 adopts a composite isolation system composed of a double-layer PCB combined with damping materials. The two PCB layers are connected via pin connectors, effectively dispersing and attenuating lateral stress and significantly reducing resonance.

The tube is placed on the second PCB layer using damping materials, providing a secondary reduction of microphonic effects. Actual measurements show that the microphonic effect is below the human ears? perceptual threshold. Among all iBasso tube amplifier products, it consistently performs at the forefront.

Dual-Battery Architecture Demonstrates Solid Power

The D17 features a dual-battery power supply architecture, with the DAC and headphone amplifier powered by separate batteries. This dual architecture ensures that the headphone amplifier section receives a stable current supply while effectively isolating digital interference.

Whether under high gain or heavy load, the D17 can consistently maintain a pure and stable output, significantly reducing distortion caused by unstable power supplies. It truly delivers a clear and pristine sound quality, capable of presenting your recordings with the utmost musical quality.

24-Position, 4-Section Stepped Attenuator

The D17 supports both analog and digital volume adjustments. The analog volume uses iBasso?s 24-position, 4-section stepped attenuator, which is only one-tenth the size of the traditional stepped attenuator while retaining all their advantages.

The difference between the left and right channels is less than ?0.1 dB. Digital volume adjustment is performed via a professional DSP module. The combination of analog and digital volume control allows for more precise volume output.

Further Technical Details

• 284 high-precision film resistors with a low temperature coefficient of 0.01% (25ppm)
• Two Nutube 6P1 vacuum tubes, with a lifespan of up to 30,000 hours
• Custom 24-position, 4-section stepped attenuator, with channel tolerance less than ?0.1 dB
• Two Accusilicon ultralow-phase noise femtosecond crystal oscillators
• Professional audio DSP chip, with a theoretical dynamic range of up to 192 dB and THD+N reaching -174 dB
• Ultralow-noise analog power supply, with noise as low as 0.6?V, which is lower than the 0.8?V of the LT304x by Linear Technology
• Dual-battery architecture, with separate batteries powering the digital and amplification sections
• iBasso custom film capacitors and vintage SPRAGUE capacitors
• 1.3-inch OLED display

Key Specs

General

Connectivity

Performance

Digital Audio

Compatibility

Power

Physical

Packaging Info