A Pocket Powerhouse
True to the core values of Astell&Kern, high fidelity sound lies at the heart of the SR25 MKII, delivering exceptional audio performance to a diverse range of music lovers. The most distinctive feature of the Astell&Kern A&norma product line is its compact form factor. However, the SR25 MKII offers more detailed sound than its predecessor, allowing the clear expression of each and every instrument and vocal note.

• A true high-resolution music player, bit-perfect playback up to 32bit/384kHz and Native DSD (DSD256)
• Dual DAC of CS43198, MasterHIFI tier chipset from Cirrus Logic and new quad-core CPU with Performance Mode for outstanding response and performance
• Improved audio quality compared to the predecessor, SR25, and Versatile connectivity with addition of 4.4mm balanced output support
• WiFi, Two-way Bluetooth (LDAC and aptX HD) for wireless streaming, plus Open APP Service for music streaming apps such as Amazon Music, Qobuz, Tidal, Spotify, Apple Music and many more!
• Supported Audio Formats: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF, MQA
• 20 hours of continuous playback and 64GB of internal memory plus 1 microSD card slot (up to 1TB cards)

The SR25 MKII offers more versatile connectivity options with the addition of a 4.4mm balanced output for the first time in an A&norma player, LDAC, as well as Qualcomm aptX HD, which support and deliver true audiophile sound quality.

The SR25 MKII is a true mass premium product
Improved audio quality compared to the SR25
Versatile connectivity with addition of 4.4mm balanced output support
Energy-efficient design resulting in 20 hours of continuous playback
Supports two-way Bluetooth and high-definition codecs (Qualcomm aptX HD, LDAC)
ReplayGain automatically maintains constant volume

The SR25 MKII keeps everything we love about the SR25 and adds new design features. It will produce the best sound quality anywhere, anytime.

General Specifications

• Model: SR25 MKII
• Body Color: Mercury D. Silver
• Body Material: Aluminum
• Display: 3.6" HD (720 x 1,280) TFT LCD
• Supported Audio Formats: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF, MQA
• Sample Rate:
  • PCM: 8kHz ~ 384kHz (8/16/24/32bits per Sample)
  • DSD Native: DSD64 (1bit 2.8MHz)
  • Stereo/DSD128 (1bit 5.6MHz)
  • Stereo/DSD256 (1bit 11.2MHz)
• Output Level: Unbalanced 2Vrms / Balanced 4Vrms (Condition No Load)
• CPU: Quad-core
• DAC: Cirrus Logic CS43198 x2 (Dual DAC)
• Decoding: Support up to 32bit / 384kHz Bit-to-Bit playback
• Input: USB Type-C input (for PC & MAC)
• Outputs: Unbalanced Out (3.5mm)/ Balanced Out (2.5mm, only 4-pole supported - 4.4m, only 5-pole supported)
• Wi-Fi: 802.11 b/g/n (2.4GHz)
• Bluetooth: V4.2 (A2DP, AVRCP, Qualcomm aptXTM HD, LDAC)
• Dimensions: 2.5" (63.5 mm)[W] x 4.26" (108.3 mm)[H] x 0.63" (16.1 mm)[D]
• Weight: about 6.27 Oz (about 178 g)
• Feature Enhancements: Firmware upgrades supported(OTA)
• Operating Temperature: 0°C ~ + 40°C )32°F ~ 104°F)

Audio Performance

• Frequency Response:
  • ±0.014dB (Condition: 20 Hz~20 kHz) Unbalanced / ±0.011dB (Condition: 20Hz~20kHz) Balanced
  • ±0.10dB (Condition: 20 Hz~70 kHz) Unbalanced / ±0.12dB (Condition: 20Hz~70kHz) Balanced
• Signal to Noise Ratio: 122dB @ 1kHz, Unbalanced / 124dB @ 1kHz, Balanced
• Crosstalk: -138dB @ 1kHz, Unbalanced / -144dB @ 1kHz, Balanced
• THD+N: 0.0006% @ 1kHz, Unbalanced / 0.0005% @ 1kHz, Balanced
• IMD SMPTE: 0.0004% 800Hz 10kHz(4:1) Unbalanced/ 0.0003% 800Hz 10kHz(4:1) Balanced
• Output Impedance: Unbalanced Out 3.5 mm (1.2 Ohm) / Balanced Out 2.5 mm (1.8 Ohm), 4.4.mm (1.7ohm)

Clock source

• Clock Jitter: 25ps (Typ)
• Reference Clock Jitter: 70ps

Battery

• Capacity: 3,150mAh 3.7V Li-Polymer Battery
• Continuous Playback Time: About 20hours (Standard: FLAC, 16bit, 44.1kHz, Unbalanced, Vol.50, EQ Off, LCD Off)
• Charge Time: About 2.5 hours (5V 2A General Charging)

Memory:

• Built-in Memory: 64 GB[NAND]
• External Memory: microSD (Max 1TB) x1

OS:

Supported OS: Windows 8,10 (32/64bit), MAC OS X 10.7, and up

Firmware

User Manual

SR25 MKII Software & Driver

Dreamus USB Audio Device Driver

SR25MKII Open Source Code