Overview: The Astell&Kern A&norma SR15 from iRiver is a portable
high-resolution music player that delivers high quality playback. The SR15 features dual DACs
(digital-to-audio converters) with balanced and unbalanced analog outputs. It has an internal memory for storing
music files, plus a microSD slot for external memory. The SR15 has a 3.3" LCD touchscreen display, plus built-in Wi-Fi and Bluetooth.
Construction: The compact SR15 is only 2-1/4"W x 3-15/16"H x
5/8"D, and weighs
5.6 ounces. It is made from dark gray aluminum, and
features an angled LCD touch screen. The SR15
comes with a protective film to help prevent scratches. Analog controls include
a rotary volume knob on the right side, and Play/pause, Previous/rewind, and
Next/fast forward buttons along the left side.
Digital Storage: The SR15 has a built-in 64 GB internal memory. You
can also insert a microSD card in the memory card slot on the side of the
device to bring the total memory capacity of 400 GB.
Dual DACs: The SR15 is equipped with two MasterHIFI class DACs,
Cirrus Logic CS43198 for a dual-DAC configuration. The device plays any
resolution of digital files up to 24-bit/192kHz, bit-for-bit. 32-bit/384kHz
audio files are downsampled to 24-bit/192kHz, while 32-bit/352kHz is downsampled
to 24-bit/176kHz for playback. In addition, DSD 128 MHz is converted to PCM for
playback. The SR15
supports the following Audio Formats and Bit Rates:
- Audio Formats: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF
- Sampling Rates:
- PCM: 8kHz - 192kHz (8/16/24 bits per sample)
- DSD Native: DSD64 (1-bit/2.8MHz), Stereo; DSD128 (1-bit/5.6MHz)
Quad-core CPU: The A&norma SR15 utilizes a Quad-core CPU to
provide extra processing power for your digital music. The Quad-core CPU makes
your digital files sound better by removing noise and reducing distortion. It
also provides a faster, more intuitive user interface to give you a more
pleasing listening experience.
USB DAC: The USB DAC function lets you connect the SR15 for
use as a sound card for your computer for better sound quality, compared to the
built-in sound card. Connect
the unit via USB from your computer and listen to your stored digital music with
headphones, powered speakers, or home stereo. The USB DAC is compatible with
Windows 7 (32-bit/64-bit), Windows 8 (32-bit/64-bit), Windows 10
(32-bit/64-bit), and Mac OS X 10.7 or later.
Supported formats include WAV, FLAC, WMA, MP3, OGG, APE (Normal, High, Fast),
AAC, ALAC, AIFF, DFF, and DSF. Sample rates: 44.1kHz - 96kHz; Bit Rate:
Balanced/Unbalanced Outputs: The Astell&Kern SR15 offers
both balanced and unbalanced outputs on the top of the device. Balanced outputs
have an additional "cold" signal to compliment the hot signal, which reduces
external noise and increases output. The balanced output is a 4-conductor 2.5mm
port. You can also connect an
external audio device to the SR15 by connecting to both the earphones port
(ground) and the balanced port (LR), using an optional balanced cable available
from Astell&Kern. Output voltages: Balanced 4.0V (1.6 ohm), Unbalanced 2.0V
User Interface: The SR15 features a high-quality user interface to
make it easy to find and select your music files, change the volume, and
adjust the sound:
- 3.3" LCD Touchscreen: The full-color 3.3" LCD touchscreen has a
resolution of 480 x 800 pixels. The screen displays the title and artist of
the currently playing song, along with elapsed and remaining time, with the
album art in the background. On the touchscreen, you can touch the
Play/Pause, Previous/Rewind, or Next/Fast Forward icons to control playback.
You can make adjustments to the EQ, set the repeat and random modes, and add
the song to a playlist, all using the touchscreen interface.
- Rotary Volume Knob: The SR15 has a side-mounted analog-style
rotary volume knob. As you adjust the volume, the volume range is shown numerically on the display.
You can change the output to "Line Out", which locks the volume level at
- Hardware Control Buttons: There are four physical buttons on the
unit: a top-mounted power button, along with side-mounted Play/Pause,
Previous/Rewind, and Next/Fast Forward buttons.
Micro-B USB: The SR15 has a Micro-B USB port on the bottom of the unit
for connecting the unit to your computer for downloading music files and for
charging the battery. The SR15 is compatible with Windows 7, 8, and 10,
as well as Mac OS X 10.7 and up.
Wi-Fi Capability: The SR15 features built-in Wi-Fi (802.11
b/g/n--2.4GHz), allowing you to connect the device and your computer to the same
network for streaming and downloading music. With the MQS Streaming Server
software installed on your PC or Mac, you can use the SR15 to access music
files stored on your computer's hard drive or a connected HDD. In addition, the
Wi-Fi connection allows you to receive notifications of new available firmware
updates (OTA Upgrades), allowing you to download them on the spot.
Bluetooth: The SR15 also has built-in Bluetooth V4.1 with
A2DP and aptX HD profiles for
connecting a Bluetooth device to listen to music wirelessly. DSD playback is not
available via Bluetooth, and performance may be limited for high-res playback;
48 kHz or lower resolution is recommended). You must maintain a distance within
8" of the paired Bluetooth device for best audio quality and connection quality.
Car audio Bluetooth connections are not supported.
AK Connect: The SR15 can stream or download music files
stored on a computer on the same network. Using the AK Connect app (available for iPad running iOS
8.0 or later
or Android devices running version 4.2 and up), you can connect to a NAS or PC
and control it with a smartphone or tablet.
Power Requirements: The SR15 is equipped with a 3150 mAh 3.7V
Lithium-Polymer battery. The battery charges via USB in about 8 hours. A fully
charged battery can provide up to approximately 10 hours of continuous playback
time (based on FLAC, 16-bit, 44.1kHz, unbalanced output, volume 80, EQ off, LCD
Protective Film: The unit includes a protective film to keep
the touchscreen and the rear panel scratch-free.
- Frequency Response:
- 20Hz-20kHz (±0.030dB Unbalanced, ±0.024dB Balanced)
- 10Hz-70kHz (±0.038dB Unbalanced, ±0.065dB Balanced)
- Signal-to-Noise Ratio (@1kHz): 122dB (unbalanced and balanced)
- Crosstalk (@1kHz): 137dB unbalanced, 131dB balanced
- THD+N (@1kHz): 0.0008% unbalanced, 0.0009% balanced
- Clock Jitter: 70ps