A Pocket Powerhouse
True to the core values of Astell&Kern, high fidelity sound lies at the heart of the SR25 MKII,
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
sound than its predecessor, allowing the clear expression of each and every instrument and vocal note.
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 keeps everything we love about the SR25 and adds new design features. It will produce the best sound quality anywhere, anytime.
- 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
Performance Mode for Ultra High Resolution Sound
Not all DACs sound the same.
The SR25 MKII delivers improved performance across the board compared to the SR25, including bass response, dynamic range, soundstage, imaging and more.
The SR25 MKII utilizes Astell&Kern's latest audio design technology for clear and natural high-resolution sound with more clearly defined upper and lower ranges providing listeners with a deeper, more rounded sound.
Bit-to-Bit playback is available in models up to the SR25 MKII 32 bit 384 kHz. Native DSD audio is available up to 11.2 MHz, for uncompressed sound quality, staying true to the artist’s original intention, in high-resolution and with minimal distortion.
With seamless playback performance supporting native DSD256 up to 32 bit/384 kHz, you will derive even more pleasure from your music.
32-bit bit-to-bit Playback by the SR25 MKII
32-bit Playback by Other Products
Multiple Output Options
The SR25 MKII supports 4.4mm balanced output.
With 2.5mm, 3.5mm and 4.4mm output options, you can connect an even wider variety of devices.
The 4.4mm balanced output provides improved dynamic range and bass response, supports a wide soundstage, offers clear imaging, and captures subtle details in the audio source.
Enjoy your music without worrying about adaptors.
SR25 MKII Output Structure>
Silver Plating Shield Can
Astell&Kern products apply shield cans so that noise and electromagnetic interference, which occur
when the countless parts are in operation, do not affect the audio block.
The SR25 MKII has taken it a step further by applying highly conductive, hyper-pure silver plating on the existing shield cans for perfect shielding that provides excellent audio performance.
Excellent Continuous Playback Time
No need to worry about battery life.
The SR25 MKII can play continuously for 20 hours with just one full charge, thanks to its optimized, energy-efficient circuitry.
Enjoy your own personal musical performance anytime, anywhere with the SR25 MKII’s extended playback time and its portability.
* Music in FLAC format, 16 bit, 44.1 kHz, unbalanced, volume at 50,
EQ Off, LCD Off
* Playback time may vary depending on the user environment.
Wireless Hi-Fi Sound Through BT Sink
The newly introduced BT Sink function connects the SR25 MKII 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 SR25 MKII using the BT Sink function.
ReplayGain Automatically and Uniformly Adjusts Playback Volume
ReplayGain, which adjusts sound sources with different volumes to an identical level, has been applied. Now, enjoy your own playlists seamlessly through the ReplayGain feature on SR25 MKII.
- ReplayGain supports up to 24bit/192 kHz sound sources.
The new AK File Drop function in the SR25 MKII makes files 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.
The A&norma SR25 MKII inherits the overall design identity of the A&norma SR25 model, highlighting
the rhythmic freedom of music through the harmonious combination of design elements.
The top and bottom edges of the bezel are angled, giving the impression of a smaller rectangle floating freely inside the chassis. The pattern on the side is designed to draw attention to the volume wheel whilst conveying an impression of sound.
Mercury D. Sliver
3.6inch HD (720 x 1,280) TFT LCD
Supported Audio Formats
WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF, MQA
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), Stereo
Unbalanced 2Vrms / Balanced 4Vrms (Condition No Load)
Cirrus Logic CS43198 x2 (Dual DAC)
Support up to 32bit / 384kHz Bit-to-Bit Playback
USB Type-C input (for charging PC & MAC)
Unbalanced Out (3.5mm), Balanced Out (2.5mm, only 4-pole supported | 4.4mm, only 5-pole supported)
802.11 b/g/n (2.4GHz)
V4.2 (A2DP, AVRCP, Qualcomm®aptXTM HD, LDAC)
2.5 ”(63.5 mm) [W] x 4.26 ”(108.3 mm) [H] x 0.63 ”(16.1 mm) [D]
about 6.27 oz (about 178 g)
Firmware upgrades supported (OTA)
0℃ ~ + 40℃ (32℉~ 104℉)
±0.014dB (Condition: 20Hz~20kHz) Unbalanced / ±0.011dB (Condition: 20Hz~20kHz) Balanced
±0.10dB (Condition: 20Hz~70kHz) Unbalanced / ±0.12dB (Condition: 20Hz~70kHz) Balanced
Signal to Noise Ratio
122dB @ 1kHz, Unbalanced / 124dB @ 1kHz, Balanced
-138dB @ 1kHz, Unbalanced / -144dB @ 1kHz, Balanced
0.0006% @ 1kHz, Unbalanced / 0.0005% @ 1kHz, Balanced
0.0004% 800Hz 10kHz(4:1) Unbalanced / 0.0003% 800Hz 10kHz(4:1) Balanced
Unbalanced Out 3.5mm (1.2ohm) / Balanced out 2.5mm (1.8ohm), 4.4.mm (1.7ohm)
- Frequency Response
Reference Clock Jitter
- Clock Jitter
3,150mAh 3.7V Li-Polymer Battery
Continuous Playback Time
about 20hours (Standard : FLAC, 16bit, 44.1kHz, Unbalanced, Vol.50, EQ Off, LCD Off)
about 2.5hours (5V 2A General Charging)
microSD (Max. 1TB) x1
- Built-in Memory
Windows 8,10 (32/64bit), MAC OS X 10.7 and up
- Supported OS
- Audio was NOT muted during the measurement.
- The image/specification may be changed without notice to improve product performance and quality.