Astell&Kern SP4000T A&ultima Hi-Res Music Player, Silver Overview
The Astell&Kern SP4000T A&ultima Hi-Res Music Player is designed for listeners who want flagship portable playback with real vacuum tube character and detailed digital control. It uses four Raytheon JAN6418 vintage vacuum tubes in a quad configuration, with Triple Tube Mode giving a choice of Triode, Ultra Linear, and Pentode operation. These work alongside Astell&Kern’s Triple AMP system, letting you switch between Tube AMP, OP AMP, and Hybrid AMP modes.
Its digital stage uses dual AK4191EQ processors and dual AK4499EX DACs, with separate digital and analogue signal paths to help reduce noise and preserve detail. High Driving Mode, ESA signal alignment, Advanced DAR upsampling, Crossfeed, ReplayGain, and seven DAC filters give plenty of scope for fine-tuning. Native DSD512, 32-bit/768kHz playback, Android 15, Roon Ready support, Qobuz Connect, BT Sink, USB PD 3.0 fast charging, and a 6-inch Full HD display make the SP4000T a powerful portable player for local libraries and modern streaming.
Product Ref: 395311
Full Description
View Full DescriptionQuad Tube Analogue Character
The SP4000T uses four Raytheon JAN6418 vacuum tubes in a balanced quad arrangement, with separate tube structures for the left and right channels. Triple Tube Mode lets you switch between Triode, Ultra Linear and Pentode operation, giving you different analogue characteristics to suit your music and headphones. This makes it easier to move between a softer, more relaxed presentation and a more direct, energetic sound while keeping the benefits of a fully balanced tube design.
Triple AMP Flexibility
Tube AMP mode focuses on the warmer character of the vacuum tubes, while OP AMP mode delivers Astell&Kern’s cleaner and more precise solid-state presentation. Hybrid AMP mode combines both approaches, with five adjustment stages that let you control how much tube character is introduced into the signal. This gives you useful flexibility when changing headphones, genres or listening conditions, allowing the SP4000T to move between analogue warmth and a more neutral, high-resolution sound.
Advanced Digital Control And Streaming
Dual AK4191EQ processors and dual AK4499EX DACs separate digital and analogue processing, helping reduce interference and maintain cleaner signal handling. Android 15 supports a modern interface alongside Roon Ready, Qobuz Connect and BT Sink for flexible streaming and wireless playback. USB PD 3.0 fast charging makes day-to-day use more convenient, while the 6-inch Full HD display gives you more space to browse music, manage settings and control both local files and network streaming services.
Features
- Four Raytheon JAN6418 vacuum tubes bring genuine valve amplification and analogue character to a portable digital audio player.
- Triple Tube Mode offers Triode, Ultra Linear and Pentode settings for adjusting the balance between warmth, richness and dynamics.
- Tube AMP, OP AMP and Hybrid AMP modes give you flexible control over warmth, clarity and overall output character.
- Three levels of tube current adjustment let you fine-tune tonal density, texture and the sense of space around instruments.
- Dual AK4191EQ processors and AK4499EX DACs separate digital and analogue duties to support cleaner, more precise signal handling.
- Native DSD512 and 32-bit/768kHz support allows the SP4000T to handle demanding high-resolution music files.
- High Driving Mode uses a parallel OPAMP configuration to increase driving capability and dynamic range while keeping noise controlled.
- ESA signal alignment technology reduces group delay, helping different frequencies reach you with more consistent timing.
- Advanced DAR upsampling uses VSE restoration before processing to provide more complete upsampling of compatible music.
- Android 15 with Astell&Kern Direct Path supports modern streaming while enabling bit-perfect playback where supported.
- Roon Ready and Qobuz Connect provide flexible options for hi-res streaming, network playback and music library control.
- A 6-inch Full HD display and USB PD 3.0 charging make browsing and everyday portable use more convenient.
Specifications
| Body Colour | SilverCopper |
|---|---|
| Body Material | Stainless SteelCopper |
| Display | 6" 2160 × 1080 2K Touchscreen |
| DAC | 2 × AKM AK4191EQ2 × AKM AK4499EX |
| Vacuum Tubes | 4 × Raytheon JAN6418 |
| CPU | Octa-Core |
| Supported Audio Formats | WAVFLACWMAMP3OGGAPEAACALACAIFFDFFDSF |
| PCM Support | 8 kHz – 768 kHz, 8 / 16 / 24 / 32-Bit |
| DSD Support | DSD64 (2.8 MHz)DSD128 (5.6 MHz)DSD256 (11.2 MHz)DSD512 (22.4 MHz) |
| Maximum Decoding Resolution | Up To 32-Bit / 768 kHz Bit-Perfect Playback |
| Output Level | 4.2 Vrms Unbalanced8 Vrms Balanced |
| USB Input | USB Type-C For Charging And PC / Mac Audio |
| Unbalanced Output | 3.5 mm |
| Optical Output | 3.5 mm |
| Balanced Output | 4.4 mm 5-Pole |
| AK Cradle Compatibility | Supported |
| Wi-Fi | 802.11 a/b/g/n/ac/ax, Dual-Band 2.4 / 5 GHz |
| Bluetooth | Bluetooth 5.2 |
| Bluetooth Profiles And Codecs | A2DPAVRCPQualcomm® aptX™ HDLDACLHDCSBCAAC |
| Frequency Response | 20 Hz – 20 kHz: ±0.006 dB Unbalanced / ±0.006 dB Balanced20 Hz – 70 kHz: ±0.06 dB Unbalanced / ±0.06 dB Balanced |
| Signal-to-Noise Ratio | 124 dB @ 1 kHz Unbalanced125 dB @ 1 kHz Balanced |
| Crosstalk | -136 dB @ 1 kHz Unbalanced-145 dB @ 1 kHz Balanced |
| THD+N | 0.0006% @ 1 kHz Unbalanced0.0004% @ 1 kHz Balanced |
| IMD SMPTE | 0.0004% @ 800 Hz / 10 kHz (4:1) Unbalanced |
| Output Impedance | 0.7 Ω (3.5 mm Unbalanced)1.7 Ω (4.4 mm Balanced) |
| Clock Jitter | 25 ps (Typical) |
| Reference Clock Jitter | 200 fs |
| Internal Storage | 256 GB NAND |
| External Storage | 1 × microSD, Up To 1.5 TB |
| Battery | 7,450 mAh, 3.8 V Li-Polymer |
| Charging Time | Approximately 5 Hours (PD 3.0) |
| Playback Time | Approximately 10 Hours |
| Supported Operating Systems | Windows 10 / 11 (32 / 64-Bit)macOS X 10.7 Or Later |
| Firmware Updates | OTA |
| Operating Temperature | 0°C – 40°C |
| Dimensions (W × H × D) | 85.7 × 150 × 19.5 mm |
| Weight | 565 g |
| Product Code | AKP28 |
| EAN | 8800309901167 |
| Reviews of our service
View all
