Astell&Kern A&ultima SP4000T Portable Music Player

Reimagine Analog Sound, A&ultima SP4000T

A&ultima SP4000T is the culmination of nearly two years of dedication and exploration, beginning from the planning and development stages of SP3000T. DAC, Tube, and AMP – the essential elements of high-end audio — may be accessible to anyone. Yet even with the same elements, what is ultimately created from them is an entirely different matter. Using the canvas of SP4000, the essence of digital sound, Astell&Kern held onto one defining question over the past two years: “How can we bring deeper emotion through analog sound?”

The answer was drawn with sincerity and endless passion, stroke by stroke. Every trace of that journey is distilled into SP4000T. Astell&Kern’s own analog sound – comfortable to listen to, yet revealing new depth and character the longer you experience it. Discover it for yourself with A&ultima SP4000T.

Triple AMP System

A&ultima SP4000T, built on Astell&Kern’s exclusive Teraton Alpha technology, achieves a perfect fusion of true analog sound from the Quad-configured Real Vacuum Tubes and the dynamic sound of the OPAMP. SP4000T offers TUBE AMP mode for the authentic analog sound of a tube amplifier, OP AMP mode delivering Astell&Kern’s signature clarity and expansive soundstage, and HYBRID AMP mode combining the best of both analog warmth and high-resolution output.

Experience a distinctly differentiated sound through the T Series‘ signature amplifier technology.

Overwhelming High Resolution and Dynamics, OP AMP Mode

High resolution that reproduces the original sound without distortion, an unparalleled sense of space, and the ultimate in clarity and dynamics — OP AMP mode delivers the pinnacle of high-quality sound that Astell&Kern has pioneered across every product. The ultra-low noise and high resolution achieved through Astell&Kern’s TERATON ALPHA technology will reveal new dimensions of music you have never experienced before, across every genre.

True Analog Sound, TUBE AMP Mode

The warm texture and unique soundstage of a Tube Amp cannot be replicated by any modern digital amplifier. Beloved since the very first appearance of tube amplifiers, they remain unmatched in conveying the emotional depth of music. SP4000T’s TUBE AMP mode pairs the deep, rich analog sound exclusive to its Quad-configured Real Vacuum Tubes with groundbreaking low noise achieved through cutting-edge technology and craftsmanship — letting you lose yourself entirely in the music.

Astell&Kern’s Advanced HYBRID AMP Mode

Beyond just two modes – Tube AMP and OP AMP, a next-generation Hybrid AMP mode lets you handpick your preferred tonal character. Combining the analog sensibility with the advantages of high-resolution output, the five-stage HYBRID AMP mode allows you to freely dial in the perfect sound for your taste and your music.

High Driving Mode for the Ultimate Sound

The SP4000T inherits the beloved High Driving Mode from the SP4000, acclaimed by audiophiles worldwide. With twice as many OPAMPs arranged horizontally, it delivers even greater sonic density. Like a four-wheel-drive vehicle conquering rough terrain, High Driving Mode channels superior driving power to produce a stronger, more stable sound – precisely articulating even the most easily missed sonic details, and designed for a deeper, more vivid listening experience.