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Delivery time approx. 1 week
Reviews
"The Astell&Kern SP4000 probably is the best DAP on the market right now from a technical point of view. The only downsides this time are the heavy price tag, the large dimensions and the heavy weight."
Astell&Kern SP4000 Review - Headfonia
"You have to be realistic, because at this flagship level, you can’t reinvent the wheel. But A&K managed to come up with a very focused, impressive finetuning where I hear notes in SP4k to have more weight and more solid body, while remaining very detailed and natural. The technical performance has improved with the sound being fuller, tighter, having a blacker background, and more holographic imaging under the new Advanced DAR implementation."
Astell & Kern A&K SP4000 – Twister6 Reviews
Portable high-end music player
The SP4000 from Astell&Kern is a milestone in digital high-end audio playback. Thanks to its innovative Octa-Audio circuit architecture, the SP4000 achieves unprecedented precision and clarity of the sound image.
Signal processing with four advanced AK4191 digital processors and four AK4499EX DACs enables precise signal transmission with drastically reduced noise levels. The ESA technology (Enhanced Signal Alignment) ensures flawless frequency coherence, so even the finest nuances are reproduced in exquisite detail. The high driving mode helps the SP4000 deliver powerful and stable output performance and create a sound image that impresses with both its dynamics and detail richness.
The SP4000 is the first Astell&Kern player with a full Android operating system. Any app like Tidal, Qobuz, Spotify, or Apple Music can be easily and quickly installed and used. The ultra-low-noise LDO regulation reduces noise levels by up to 97 percent compared to previous models. The Any-Layer Technology HDI-PCB and a shield made of 99.9 percent pure copper ensure maximum signal purity and reduce electromagnetic interference.
The elegant 6-inch display with 2K resolution and the new Generation 4.5 user interface combine functionality and design. The polished 904L stainless steel body and the PVD-coated ceramic back unite technological perfection and sophistication. A custom leather case made from the finest Perlinger calf leather completes the package.
The SP4000 supports high-resolution PCM up to 32-bit/768 kHz as well as DSD512 and offers versatile options with 3.5 mm and 4.4 mm headphone outputs and Bluetooth. With up to 10 hours of playback time and 256 GB internal storage expandable by microSD up to 1.5 TB, the SP4000 is the ultimate choice for audiophile music lovers.
SP4000 Highlights
- Enhanced signal processing with octa-audio circuit design
- High driving mode for premium sound quality
- Proprietary Enhanced Signal Alignment (ESA) technology minimizes group delays
- Ultra-low-noise LDO regulator for premium noise suppression
- Advanced Digital Audio Remaster (DAR) technology
- Full support for Android operating system
- New Generation 4.5 User Interface
Connections
- 3.5 mm asymmetrical headphone output / optical output
- Symmetrical 4.4mm headphone output (supports only 5-pin plugs).
- USB-C input (for charging the battery and data transfer from a PC/Mac).
- WiFi 2.4/5GHz
- Bluetooth V5.0
Specifications
The SP4000 is the first device from Astell&Kern to fully support the Android operating system. Any app like Tidal, Qobuz, Spotify, or Apple Music can be easily and quickly installed and used. The SP4000 not only delivers flagship-level audio quality but also offers exceptional comfort, making it a sophisticated digital audio player.
The Octa-Audio circuit architecture offers enhanced signal processing capabilities. Through continuous research and innovation in circuit technology, Astell&Kern has succeeded with the SP4000 in developing a true quad DAC—a feat previously considered impossible due to noise and other issues—and thereby achieving an impressive signal-to-noise ratio.
The High Driving mode enables precise reproduction of the finest sound details, allowing you to enjoy your music even clearer and more intensely.
The ESA technology (Enhanced Signal Alignment) aligns frequency signals so they arrive more evenly, minimizes frequency distortion, and significantly improves the clarity and purity of the sound.
The LDO regulator (Low Dropout) of the power supply reduces unwanted noise by up to 97% compared to previous models, resulting in an exceptionally clean and pure sound.
The Any Layer HDI (High-Density Interconnect) circuit board technology enables the precise design of complex circuits in a very small space. It minimizes signal loss and delivers an even finer and more detailed sound.
The shielding made of 99.9% pure copper prevents noise and electromagnetic interference, ensuring that the sound is clearer and sharper than ever before.
Astell&Kern's DAR technology (Digital Audio Remaster) helps produce an even more natural and refined sound. Instead of sending the audio file directly to the DAR engine, the SP4000 first uses the VSE (Virtual Sound Extender) to virtually restore lost overtones in the first phase and improve sound quality. Then, in the second phase, the enhanced DAR engine performs oversampling with greater accuracy and completeness. Thanks to this two-step approach, you hear a deeper and more penetrating sound that is closer to the original recording than ever before.
The user interface of the SP4000 has been updated to offer even more features and an emotional experience. The SP4000 captivates both visually and tactilely with its refined and modern design.
The SP4000 comes with a high-quality leather case made by Perlinger, the world-famous German leather house, crafted from calf leather. After an aniline dyeing process, Perlinger's own pigments are added to achieve a deep, radiant color. The advanced anti-aging treatment ensures that this radiant color lasts a long time and completes the SP4000 with a leather case that embodies lasting beauty, durability, and luxury.
Enhanced signal processing capabilities with Octa-Audio circuit architecture
In the SP3000, the structure for digital and analog signal processing was separated in a 1:2 ratio. In the SP4000, it has been developed into a 1:1 architecture.
This new structure, where a digital processor AK4191 is paired with a DAC AK4499EX, enables precise transmission of digital signals to a single DAC without distributing noise, allowing improved signal separation and processing.
Through continuous research and innovation in circuit technology, it has been possible to implement a true Quad DAC in the SP4000 – a feat previously considered impossible due to noise and other issues. This allows the SP4000 to achieve an impressive SNR (Signal-to-Noise Ratio) of 131 dB, matching the independent dual-audio circuit of its predecessor.
Technical details
- 6-inch touchscreen with 2K resolution (2160x1080).
- Case material: Stainless steel 904L
- CPU: Octa-Core
- DAC: 4x AKM4191 + 4x AKM4499EX (True Quad DAC).
- Decoding: up to 32 Bit/768 kHz bit-perfect playback.
- Bluetooth V5.0 (A2DP, AVRCP, aptX Adaptive, LDAC)
- WiFi 802.11 a/b/g/n/ac (2.4/5GHz)
- Supported audio formats: WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF.
- Sampling rates:
PCM: 8 kHz ~ 768 kHz (8/16/24/32 Bit per sample).
Native DSD: DSD64 (1 Bit 2.8MHz), stereo / DSD128 (1 Bit 5.6MHz), stereo / DSD256 (1 Bit 11.2MHz), stereo / DSD512 (1 Bit 22.4MHz), stereo. - Output level: Asymmetrical 4.1 Vrms / Symmetrical 8.2 Vrms (no load).
- Frequency range:
Asymmetrical: ±0.006dB - 20 Hz ~ 20 kHz.
Symmetrical: ±0.006dB - 20 Hz ~ 20 kHz
Asymmetrical: ±0.06dB - 20 Hz ~ 70 kHz
Balanced: ±0.06dB - 20 Hz ~ 70 kHz - SNR: Unbalanced 129 dB @ 1kHz / Balanced 131dB @ 1kHz.
- Crosstalk: Unbalanced -136dB @ 1kHz / Balanced -145dB @ 1kHz.
- THD+N: Unbalanced 0.0005% @ 1kHz / Balanced 0.0003% @ 1kHz.
- Output impedance: Unbalanced 3.5 mm 0.7 Ohm / Balanced 4.4 mm 1.7 Ohm
- Clock jitter: 25pS (typical)
- Reference clock jitter: 200 femtoseconds
- Internal memory: 256 GB (NAND).
- microSD card slot for memory expansion (max. 1.5 TB).
- Battery: 6780 mAh 3.8V Li-Polymer.
- Battery life: approx. 10 hours (Standard: FLAC, 16 Bit, 44.1kHz, Vol. 80, LCD Off, Low Gain).
- Charging time: approx. 4 hours (QC3.0 Charging).
- Dimensions: 85 x 149.8 x 19.5 mm.
- Weight: 615 grams.
Scope of delivery
- Astell&Kern SP4000
- Elegant calf leather case from the German tannery Perlinger.
- USB cable (USB-C to USB-A)
- Protective film for the screen
- Quick start guide (German, French, English)
- User manual stored on the player in PDF format (German, French, English)
