Astell & Kern A&futura SE300 Music Player With R-2R DAC

The Future of Analog Sound, SE300

A&futura from Astell&Kern is a product line that represents Astell&Kern’s ceaseless efforts for innovation. SE300, the fourth model in the A&futura range is a premium digital audio player that inherits this identity and expands the scope of sound with an entirely new implemented technology.

A&futura SE300 is equipped with an ultra-refined R-2R DAC, Class A/AB dual amps born with our proprietary TERATON ALPHA technology, and for the first time a self-developed FPGA optimized technology. With these unrivaled components, it offers the true sound philosophy and technology of Astell&Kern.

Immerse yourself into the true analog sound that the SE300 produces with Class-A AMP and R-2R DAC technologies, for the first time in an Astell&Kern player.

• Fully Discrete 24 bit R-2R DAC
• Equipped with 96 ultra-precision 0.01% & TCR10 resistors
• New Dual AMP (Class A/AB) mode
• Option for OS / NOS modes
• Implemented self-developed and optimized FPGA technology
• New Crimson theme UI/UX
• Supports Bluetooth 5.0 and wireless Hi-Fi aptX™ HD, LDAC

Fully Discrete 24bit R-2R DAC

To ensure the A&futura SE300 audio player better reproduces analog sounds, we set out to combine the DAC and AMP sections for the first time during the initial design phase.

The SE300 comes supplied with an R-2R DAC, instead of a Delta-Sigma DAC that is most commonly used in other audio players. R-2R DAC, also known as Ladder DAC, as it arranges resistors in a ladder form, offers natural yet dynamic Hi-Fi sounds, but it is extremely technical and difficult to execute as it requires complex refined resistor units and hard to manage current controls. However, despite these technical challenges, after several years for development and a lot of trial and error we have managed to overcome this and create a new analog sound. In the process, we have meticulously selected each and every one of the 96 ultra-precision resistors and finalized our R-2R DAC technology.

SE300 takes us one step closer to realizing analog sound from a digital source and is the result of a long journey taken by Astell&Kern with uncompromising craftsmanship to find the ultimate sound solution.

Realization of 24-bit Decoding with R-2R DAC
The R-2R DAC within the SE300 arranges 48 pairs (23xR and 25x2R) of 96 ultra-precision resistors to create analog signals, in turn realizing true Hi-Fi 24-bit decoding.

Ultra-precision resistor Design, the Key to Hi-Fi Sound
It is key to total the accurate current value with resistors that has the smallest error ranges in order to create Hi-Fi sound with an R-2R DAC. To realize this, Astell&Kern inspected each specifically selected ultra-precision resistor of 0.01% error range to complete the design of SE300.

Ultra-precision TCR10 Specifications
To create Hi-Fi sound without distortions within such an extreme precision design, we analyzed and preconceived any potential impacts that may be caused by changes in temperature. The SE300 comes with special *TCR10 specifications to minimize the changes in the 0.01% resistor error range.

* TCR10: 10 ppm/℃ Low Temperature Coefficient of resistor

Supporting Class A/AB Dual AMP Mode

The SE300 comes with a Dual AMP mode. Class A amplification that creates low distortions and natural sounds and a Class AB amplification that plays dynamic sounds with high efficiency so users can pick and choose from the two amps according to their listening preferences and genre of music that they are playing.

Experience the true sounds that only Astell&Kern can deliver with the SE300 that comes with an R-2R DAC and Class A/AB Dual AMPs born from Astell&Kern’s unique proprietary designs that reduces power consumption whilst enhancing output and removing noise.

Class A AMP mode
Class A AMP is an analog amp that offers the best linear output, amplifying signals without distortion or loss of signal and providing soft, warm, and natural sounds. The refined analog signal created directly by the R-2R DAC, reproduces a sound closest to the original analog audio through the organic and powerful Class A AMP.

Class AB AMP Mode
Class AB AMP is an analog amp that offers a powerful output with the added benefit of high efficiency. This presents dynamic and crisp sounds with less harmonic distortion.

2-Step Gain Mode for the Perfect Hi-Fi Experience

For seamless use of sensitive IEMs and hard to drive headphones, a device must provide suitable output, respective of the connected device’s specification.

The SE300 supports a 2-step Gain Level mode to create the prefect match for a wide range of headphones and IEMs, maintaining an optimal sound output. The two-step gain setting with “Normal” and “High Gain” modes can generate a high current output to create a powerful sound and excellent driver control.

With up to 6 Vrms from the balanced connections, driving high-impedance headphones has never been easier.

Output Level

• Normal Gain: Unbalanced 2Vrms, Balanced 4Vrms
• High Gain: Unbalanced 3Vrms, Balanced 6Vrms

* Based on condition no load, there may be differences depending on the measurement method.

TERATON ALPHA, The Essence of A&K Audio Technologies

It would not have been possible to combine the exquisitely designed R-2R DAC with ultra-precision resistors and Class A AMP, which was considered impossible to miniaturize, without the innovative audio technology of TERATON ALPHA. SE300 is an innovative audio player that is applied with current and temperature control of TERATON ALPHA technology and an optimized FPGA design.

TERATON ALPHA, engineered through endless research, is Astell&Kern’s unique technology that has been designed to produce audio playback that is as close to the original sound through effective power noise removal, efficient power management and unwavering amplification, and a fully converted audio output interface.

Circuit structures of R2R DAC and Dual A/AB AMP that are applied for the first time in the SE300 is completed with the sound solution of TERATON ALPHA, creating the purest form of sounds and music.

Supporting Optimized FPGA OS / NOS Modes

The SE300 comes with Astell&Kern’s exclusively developed FPGA and provides optimized OS / NOS modes.

The SE300 uses an FPGA (Field Programmable Gate Array) that we self developed for optimized design instead of using common off the shelf commercial semiconductor chipsets, relaying digital signals to the R-2R DAC through its algorithm. Astell&Kern’s FPGA, developed specifically for the SE300, supports the most ideal OS (Over Sampling) / NOS (Non-Over Sampling).

Enjoy the sound styles reproduced by NOS and OS modes, meticulously designed for the SE300’s hardware and programs.

NOS (Non-Over Sampling) Mode

In NOS mode, the player reproduces the pure original sound without any digital processing, allowing users to enjoy the true unprocessed sounds decoded by the R-2R DAC itself.

OS (Over Sampling) Mode
OS mode offers partial digital processing that expands the bandwidth of the original signal to offer impressive details, with an expansive sense of space creating crisp and clear sounds.

OS Option		Maximum Conversion Rate
PCM	OS Mode	Supports up to 8x conversion 44.1kHz range PCM will be converted to 352.8kHz for playback 48kHz range PCM will be converted to 384kHz for playback
PCM	NOS Mode	BYPASS (ex. 44.1kHz => 44.1kHz)
DSD	OS/NOS Mode	Supports up to DSD 256 for playback

New Experience, New User Interface

The SE300 comes with a redesigned Crimson-themed UI/UX transforming into a “true music player” for users to deeply connect with their music listening experience.

The new UI/UX is designed so that users can quickly browse music categories and re-discover songs within their music library. We also added an easy album art search function so that users can re-discover the joy of viewing and interacting with music album art whilst listening to their music.

The crimson theme focuses on edge, simplicity, and dark mode keywords. The color theme of black with red highlights lowers visual fatigue and offers intuitive user experiences, and many other improvements were made to the device’s user-friendliness of app service, artist view, album sorting, and the album art search function. Immerse yourself in music with the new UI/UX.

Real-Time Information Confirmed by Light

Behind the exquisite A&futura SE300 volume wheel is an LED light that is reminiscent of rising waves. With the LED light that radiates from the inside of the SE300, users can check the Bit Depth information of the currently playing music or the current AMP mode.

* The LED can be turned on or off according to the user’s preference.

• RED 16bit
• GREEN 24bit
• BLUE 32bit
• VIOLET DSD

Other features

Adoption of 5.46 inch Full HD Display

Experience the SE300 more vividly and comfortably with a wide 5.46-inch, large-screen Full HD display.

Supports Native DSD256, 32bit/384kHz

SE300 supports DSD256 and up to 32bit/384kHz with Astell&Kern’s unrivalled audio technology, allowing you to fully enjoy your favorite music anywhere you like.

ReplayGain Automatically and Uniformly Adjusts Playback Volume

ReplayGain, which adjusts sound sources with different volumes to an identical level, has been incorporated. Now, enjoy your own playlists seamlessly through the ReplayGain feature on SE300. * ReplayGain supports up to 24-bit/192 kHz sound sources.

AK File Drop to enjoy wireless transfers

The new AK File Drop function in the SE300 makes file transfers easier and more convenient. Using AK File Drop, you can freely transfer files wirelessly through a PC, smartphone, or FTP program located on the same network. Music file management is now possible with a cableless, wireless solution.

Wireless Hi-Fi Sound Through BT Sink

BT Sink function connects the SE300 to an external device via Bluetooth, similar to connecting a smartphone with a BT speaker. Music from an external device, such as a smartphone can now be played back in high-quality on the SE300 using the BT Sink function.

DESIGN

The design concept for the A&futura SE300 is ‘Stream’. Like small ripples on water turning into crashing waves, we designed the SE300 with Class A AMP, the ultimate AMP form, to have a unique identity.

The main body made from aluminum has streamlined surfaces that represent the flow of music. Through this, we create a firm yet flexible image. We added intensity by using contrasting materials such as stainless steel and glass to further enhance the theme of ‘Stream’. In addition to this, the bottom section of the device curves outward, allowing for a more ergonomic grip whilst using the player.

The right side of the SE300 is coated with stainless steel to enhance visual focus. The polished side and triangular-patterned volume wheel are key to creating powerful and visually striking contrasts. The straight pattern on the rear of the volume wheel elevates the visual density and allows users to control volume and visually check the changes. The wheel lighting is placed behind the volume wheel to avoid direct exposure whilst allowing the light to be reflected on the side decorations and volume wheel knurl, creating the effect of light bursting from the inside.

The rear glass also features a new etching pattern, continuing the concept of ‘Stream’ The basic pattern features the A logo of Astell&Kern, designed to present an overall flow of stream with differences in size. This etching pattern amplifies the sense of flow with the differences in inclinations, adding a sense of depth to the rectangular rear glass that may otherwise look dull.

Specification

General Specifications

• Model

  SE300

• Body Color

  Platinum Silver

• Body Material

  Aluminum and Stainless Steel

• Display

  5.46inch HD 1080 x 1920 touch screen

• Supported Audio Formats

  WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF

• Sample rate

  PCM : 8kHz ~ 384kHz (8/16/24/32bits per Sample)
  DSD : DSD64(1bit 2.8MHz), Stereo / DSD128(1bit 5.6MHz), Stereo / DSD256(1bit 11.2MHz), Stereo

• Output Level
  [Normal] Unbalanced 2Vrms │ Balanced 4Vrms (Condition No Load) [High] Unbalanced 3Vrms │ Balanced 6Vrms (Condition No Load)

• CPU

  Quad-core

• DAC

  Full Discrete R-2R

• Decoding

  Support up to 32bit / 384kHz playback

• Input

  USB Type-C input (for charging & PC & MAC)

• Outputs

  Unbalanced Out (3.5mm), Optical Out(3.5mm)
  Balanced Out (2.5mm, only 4-pole supported | 4.4m, only 5-pole supported)

• Wi-Fi

  802.11 a/b/g/n/ac (2.4/5GHz)

• Bluetooth

  V5.0 (A2DP, AVRCP, Qualcomm® aptX™ HD, LDAC)

• Dimensions

  3.01” (76.45mm)[W] x 5.49” (139.45mm)[H] x 0.69” (17.6mm)[D]

• Weight

  About 11.18oz (317g)

• Feature Enhancements

  Firmware upgrade supported (OTA)

• Operating Temperature

  0℃ ~ + 40℃ (32℉~ 104℉)

Audio Performance

• Frequency Response

  ±0.038dB (Condition : 20Hz~20kHz) Unbalanced │Balanced
  ±0.45dB (Condition : 20Hz~70kHz) Unbalanced │Balanced

• S/N

  114dB @ 1kHz, Unbalanced │ 115dB @ 1kHz, Balanced (Normal Gain)
  115dB @ 1kHz, Unbalanced │ 115dB @ 1kHz, Balanced (High Gain)

• Crosstalk

  -135dB @ 1kHz, Unbalanced │ -144dB @ 1kHz, Balanced

• THD+N

  0.006% @ 1kHz, Unbalanced │ 0.006% @ 1kHz, Balanced

• IMD SMPTE

  0.005% 800Hz 10kHz (4:1) Unbalanced │Balanced

• Output Impedance

  Unbalanced Out 3.5mm (1.3ohm) │ Balanced Out 2.5mm (1.3ohm), 4.4mm(1.3ohm)

Clock Source

• Clock Jitter

  25pS (Typ)

• Reference Clock Jitter

  500 Femto Seconds

Storage Capacity

• Built-in Memory

  256GB [NAND]

• External Memory

  microSD x1 (Max. 1TB)

Battery

• Capacity

  5,050mAh 3.8V Li-Polymer

• Charge Time

  about 3.5hours (9V 1.67A Charging)

• Playback Time

  about 12hours (Standard : FLAC, 16bit, 44.1kHz, Vol.50, LCD Off, Normal Gain)

Supported OS

• Windows 10,11(32/64bit) MAC OS X 10.7

Note: Audio was NOT muted during the measurement. – The image/specification may be changed without notice to improve product performance and quality.