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  • Astell&Kern SP4000 - Black - Open Box, Like New
Out of Stock - Allows Pre-Orders

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  • Astell&Kern SP4000 - Black
  • Astell&Kern SP4000 - Silver

Astell&Kern SP4000

Flagship Digital Audio Player

  • Enhanced signal processing with Octa audio circuit architecture
  • Supports High Driving Mode for premium sound quality
  • Minimizes group delay using ESA (Enhanced Signal Alignment) technology
  • Ultra Low Noise LDO Regulator for top-tier noise suppression
  • Precision sound with Any Layer Type PCB
  • Equipped with 99.9% Pure Copper Shield Can
  • First Astell&Kern device to support full Android OS
  • First Astell&Kern device to feature advanced DAR technology
  • Features 4.5th generation UI with functionality and emotional design
Regular price £3,799.00
Sale price £3,799.00 Regular price
Unit price

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Black
Silver
Black - Open Box, Like New

  • Estimated Delivery:Dec 08 - Dec 12

Astell&Kern SP4000

Astell&Kern SP4000

As part of the A&ultima series—Astell&Kern’s flagship lineup combining cutting-edge technology and top-tier specifications—the SP4000 surpasses the boundaries set by the SP3000, once regarded as the ultimate reference.

Built upon an advanced Octa audio circuit architecture, the SP4000 distills the purest essence of audio engineering, delivering a sound experience unlike anything before it—refined, powerful, and remarkably close to perfection. Discover the SP4000 and experience sound on an entirely new level.

Enhanced Signal Processing Capabilities with Octa Audio Circuit Architecture

In the SP3000, the digital-to-analog signal processing structure was separated in a 1:2 ratio. With the SP4000, it has evolved into a 1:1 architecture. This new structure, where one AK4191 digital processor is paired with one AK4499EX DAC, allows digital signals to be delivered precisely to a single DAC without the need to distribute noise, enabling improved signal separation and processing. Through continuous research and innovation in circuit technology, the SP4000 successfully implements a true Quad DAC—a feat previously considered impossible due to noise and other issues. As a result, the SP4000 achieves an impressive SNR (Signal-to-Noise Ratio) of 131dB, on par with the independent dual audio circuit of its predecessor.

Supports High Driving Mode for Premium Sound Performance

The SP4000 features twice as many OPAMPs arranged in parallel compared to its predecessor, delivering richer and more detailed sound. High Driving Mode provides powerful and stable output—much like a four-wheel-drive vehicle confidently navigating rough terrain. It’s designed to reproduce even the most delicate sonic details with precision, allowing you to enjoy deeper, clearer, and more immersive music.

Top-Tier Noise Suppression (Ultra Low Noise LDO Regulator)

The SP4000 features a newly implemented LDO (Low Dropout) Regulator in its power supply,which reduces noise by up to 97% compared to previous models. LDO Regulators are high-performance components typically used in precision medical devices and 5G communication equipment. They help stabilize battery voltage and effectively suppress noise, resulting in cleaner, purer sound.

To achieve the highest sound quality, the SP4000 incorporates top-tier Any Layer HDI (High-Density Interconnect) PCB technology. Commonly used in smartphones and high-performance electronic devices, this advanced circuit board allows for the precise design of complex circuitry within a compact space. It minimizes signal loss, enabling the delivery of a more refined and detailed sound.

The SP4000 is equipped with a precision-engineered Shield Can to block various types of noise and electromagnetic interference that could affect the audio block. For the first time in Astell&Kern's lineup, a 99.9% pure copper Shield Can is used—providing not only exceptional shielding performance but also delivering sound that is clearer and more distinct than ever before.

Sound Design With DAC Filters

With the SP4000, you can enjoy the fun of creating your own sound style by directly selecting various DAC filters provided by the DAC manufacturer. Design your own sound through 6 DAC filters.

Sound Type
 
Impulse Response
 
Filter name
 
Remarks
 
Edge
  • Natural TonewaveSuper Slow Roll-offNo echo reproduces
    natural sound    Ultra-Sharp
  • Acoustic TonewaveShort Delay Slow Roll-offMinimal echo reproduces
    original sound    Sharp
  • Traditional TonewaveSlow Roll-offMinimal echo reproduces
    original sound    Middle
  • Harmonic SoundwaveLow dispersionShort echo reproduces
    original sound    Middle
  • Acoustic SoundwaveShort Delay Sharp Roll-offPost echo enhances
    bass sound    Sharp
  • Traditional SoundwaveSharp Roll-offPre and post echoes make
    powerful sound    Slow

Material Innovations

To achieve the goal of the A&ultima series, which is 'to provide the best value that no one can imitate while using the most innovative and uncompromising design and craftsmanship', the SP4000 uses 904L stainless steel material that has never been attempted before in a portable audio player. Using this material has expanded its value from just a digital device to the realm of a luxury good.

904L stainless steel is harder and more difficult to process than general stainless steel requiring significantly more time and effort. However, due to its excellent durability and corrosion resistance, it has a characteristic that does not lose its beauty and is why it is used in expensive luxury watches where perfection in all materials and parts must be pursued with an irreplaceable and wonderful luster. Experience the uncompromising beauty and luxury of the SP4000 produced by Astell&Kern’s experienced craftsmanship.

Real-Time Information with LED Lights

The LED light surrounding the power button provides information on the Bit Depth of the currently playing song, and also adds a visually pleasing element by making it shine and stand out.

Technical Details

General Specifications

  • SP4000 (PPF51)

  • Black, Silver

  • Stainless Steel 904L

  • 6-inch 2K (2160 x 1080) touch screen

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

  • PCM: 8kHz ~ 768kHz (8/16/24/32bit), DSD Native: DSD64 ~ DSD512 (Stereo)

  • Unbalanced: 4.1Vrms, Balanced: 8.2Vrms (No Load)

  • Octa-core

  • AKM4191 x4 + AKM4499EX x4 (Real Quad DAC)

  • Up to 32bit / 768kHz Bit-to-Bit playback

  • USB Type-C (charging & PC/MAC)

  • 3.5mm Unbalanced, 3.5mm Optical, 4.4mm Balanced (5-pole)

  • Wi-Fi 802.11 a/b/g/n/ac (2.4/5GHz), Bluetooth V5.0 (aptX HD, LDAC, LHDC, SBC, AAC)

  • 85mm (W) x 149.8mm (H) x 19.5mm (D)

  • 615g (21.7oz)

  • OTA upgrade supported

  • 0℃ ~ +40℃ (32℉ ~ 104℉)

Audio Specifications

  • ±0.006dB (20Hz~20kHz) │ ±0.06dB (20Hz~70kHz)

  • 129dB (Unbalanced) │ 131dB (Balanced)

  • -136dB (Unbalanced) │ -145dB (Balanced)

  • 0.0005% (Unbalanced) │ 0.0003% (Balanced)

  • 0.0004% (800Hz/10kHz, 4:1)

  • 3.5mm: 0.7Ω │ 4.4mm: 1.7Ω

Clock Source

  • 25pS (Typ)

  • 200 Femto Seconds

Storage

  • 256GB NAND

  • microSD x1 (Max. 1.5TB)

Battery

  • 6,780mAh 3.8V Li-Polymer

  • About 4 hours (QC3.0)

  • About 10 hours (FLAC 16bit 44.1kHz, Vol.50, LCD Off)

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