To answer the question of how you can add deeper emotion through analog sound, the A&ultima SP4000T High-Resolution Digital Audio Player from Astell & Kern incorporates four Raytheon JAN6418 vacuum tubes. The tube's influence on your music can be customized with three tube modes, a triple AMP system, and tube current adjustment. This is in addition to dual DACs, each with dedicated processors, and various technologies designed to provide lossless playback, reduced noise, and a uniform volume. Operate it all through a 6" HD touchscreen with LED analog volume knob, playing music from built-in memory, microSD, or wirelessly, over Wi-Fi or Bluetooth.
Portable Vacuum Tubes
What you would normally find in a high-end home amplifier is now in the palm of your hand. The SP4000T features four Raytheon JAN6418 vacuum tubes, consisting of two pair, one for each channel of audio. The left and right channels have been meticulously matched for balanced audio. Using their 2nd gen anti-microphonic noise architecture, the tubes are fully isolated through independent modular flexible PCBs for warm, amplified music without the noise.
Triple Tube Mode
Three tube modes are joined with a triple AMP mode and tube current level adjustment for a true analog sound palette. A palette with up to 54 combinations to fit most any genre of music. The three tube modes are Triode, Ultra Linear, and Pentode.
- Triode Mode: Choose it for delicacy, as it is designed to bring out rich harmonic texture form the vacuum tubes. It's characterized by low output, low distortion, low efficiency, and smooth, delicate tones.
- Ultra Linear Mode: Choose it for balance, this mode blends the tonal color of Triode with the output of Pentode, rendering every musical genre with authority. It's characterized by mid output, similar distortion to Triode, relatively high efficiency, and a firm, yet smooth tone.
- Pentode Mode: Choose it for dynamics, this mode maximizes the tube amplifier output and dynamic range. It keeps the vacuum tube warmth without reverb. It's characterized by a high output, higher distortion than Triode, high efficiency, and a dynamic, clean tone.
Triple AMP System
Experience music through three different amp systems that deliver their own unique sound profiles. The system consists of OP AMP, Tube AMP, and Hybrid AMP modes.
- OP AMP mode: Using Astell & Kern's TERATON ALPHA technology, this mode is designed to reproduce your music's original sound without distortion. Deliver high resolution, clarity, and dynamics with ultralow noise.
- Tube AMP mode: This mode takes advantage of the real quad vacuum tubes to achieve emotional depth and warm textures that only tubes can provide.
- Hybrid AMP mode: A five-stage mode that lets you dial in the sound that best suits your taste, combining the warmth of Tube AMP with the high resolution of OP AMP mode.
Tube Current Adjustment
Choose from High, Mid, or Low. These safe operating ranges of the vacuum tubes, which you can adjust to alter the tonal texture of your music. These subtle yet striking changes are well suited for listening via headphones or IEP.
Separate Processing
Instead of digital-to-analog processing happening within the DAC, each of the two AK4499EX DACs are paired with dedicated AK4191EQ processors that use delta-sigma modulation to reduce digital noise before passing it to the DAC.
Digital Audio Remaster
Astell & Kern's second generation DAR technology (Digital Audio Remaster) works to elevate audio quality with analog-like richness. The SP4000T uses a VSE (Virtual Sound Extender) to restore lost harmonics. This two-step process gives you precision and completeness in addition to the analog warmth and nuance.
Proprietary ADP
Proprietary ADP (Astell & Kern Direct Path) technology makes it possible, even in streaming, for bit-perfect, lossless playback without Android's sampling limitation.
Crossfeed Mixing
Sound from one channel is sent to the other with a timing difference that works to center the sound image. You have the option of selecting Shelf Cutoff, Shelf Gain, or Mixer Level to customize your level of crossfeed.
ReplayGain
Uniform volume is possible with ReplayGain, which automatically adjusts the audio sources with varying volume levels to achieve uniformity. The feature works on personalized playlists and supports up to 192 kHz / 24-bit sources.
Wireless Hi-Fi with BT Sink
Use the BT Sink function to wirelessly send audio from an external device through the SP4000T via Bluetooth to utilize its processing for Hi-Fi results.
Additional Details
- 6" 2160 x 1080 display
- Up to 10 hours of battery life
- 256GB of built-in storage
- microSD slot supports up to 1.5TB
- See the vacuum tubes glow in Tube or Hybrid mode
- High Driving mode with parallel OP AMPs for a strong and stable sound
- Proprietary ESA for minimal group delay
- Multilayered TERATON ALPHA processing for sound faithful to the original source
- Any Layer HDI PCB for a small size with minimal signal loss
- 99.9% pure copper shield can helps block noise and EMI
- Seven selectable DAC filters for audio customization
- Enhanced battery protection mode
- LED lights around volume knob visually denote track bit depth
- Native DSD512, 32-bit / 768 kHz support
- Dual-antenna design for faster and more stable downloads
- Roon Ready
- Qobuz Connect support
- Android 15 OS
UPC: 810194100307