Description
The Astell&Kern A&ultima SP4000 in Silver is a flagship digital audio player built for listeners who demand uncompromising audio fidelity in a portable form. Running full Android with Google Play, it gives direct access to streaming services including TIDAL, Spotify and Qobuz while maintaining bit-perfect playback through Astell&Kern's proprietary ADP (Astell&Kern Direct Path) engine.
At its heart lies a true Quad-DAC Octa-Circuit architecture—four AK4191 digital processors paired one-to-one with four AK4499EX DACs—achieving a 131 dB signal-to-noise ratio. The High Driving Mode employs a parallel op-amp configuration to deliver substantial power for demanding headphones and IEMs. Proprietary ESA (Enhanced Signal Alignment) technology minimises group delay for improved clarity and imaging, while Advanced DAR v2 with Virtual Sound Extender restoration enhances detail in compressed audio.
An ultra-low noise LDO regulator cuts power supply interference by up to 97%, and a 99.9% pure copper shield can blocks electromagnetic noise. The precision any-layer HDI PCB keeps signal loss minimal within the compact chassis.
Specifications
| DAC Architecture | True Quad-DAC Octa-Circuit (4× AK4191 digital processors paired 1:1 with 4× AK4499EX DACs) |
| Signal-to-Noise Ratio | 131 dB |
| Operating System | Full Android with Google Play, Astell&Kern Direct Path (ADP) for bit-perfect playback |
| Amplification | High Driving Mode with parallel op-amps (2× parallel configuration) |
| Enhanced Signal Alignment | Proprietary ESA technology reduces group delay, improves clarity and imaging |
| Power Supply Noise Reduction | Ultra-Low Noise LDO Regulator (up to 97% noise reduction) |
| PCB Technology | Any Layer HDI (High-Density Interconnect) |
| EMI/RF Shielding | 99.9% pure copper Shield Can |
| Digital Audio Remaster | Advanced DAR v2 with Virtual Sound Extender (VSE) restoration |
| Colour | Silver (AKP22) |
| Barcode (Silver) | 8800309909033 |
