Astell & Kern continue innovating their flagship DAP series with the new SP4000T. Advertised as a successor to both the 3000T and standard 4000, the SP4000T boasts seamless analog sound through the first quad-tube configuration in a digital audio player. The 4000T also keeps to the trends of its inspirations with serious customization potential, further encouraged by the aforementioned tube capabilities. How does this new technology fare on its own, as well as alongside its predecessors?
What You Get:
- SPT4000T
- Protective Film
- MicroSD Card Slot Cover
- USB Type-C Cable
- Quick Start Guide
- Warranty Card
Build Design
Astell & Kern’s design philosophy with all their DAP series is to retain what is not broken; an understandable strategy considering they look great. The polygonal cuts of the 4000T’s stainless steel shell strongly reflect the neon-red lighting of the volume wheel and UI theme, illuminating a device as otherworldly as you would want a flagship to be. While it might not reinvent the A&ultima line, nor the standard 4000 model, additions the 4000T makes for the tube setup provide their own flair. A window at the back exposes the tubes, enunciating the product’s primary selling point. When the tube amplifiers are toggled, either through the Android UI or the additional tube button, it will glow the same red that peeks out under the volume wheel.
My only concern for such a figurative and literal metal design is portability, but with a device this luxurious the only portability you would likely be concerned with is moving around the room, which is more than manageable.
Feature Design
The central thesis of the 4000T is the first-of-its-kind quad tube setup. Running four Raytheon JAN6418 vacuum tubes, this outing of the “T” series separates itself from the 4000 with exclusive processing capability and customization. Triple-tube mode is another industry first, opening the tubes to three modes of operation to maximize tube potential. Triode Mode gives a lusher, low output sound. Pentode Mode is the opposite, enunciating precision and force. Ultra Linear Mode balances the Triode’s smoothness with the polish of Pentode.
This system can be further empowered by the triple amp introduced with the 3000T, giving options for OP amp, tube amp, and hybrid settings. Switching between them is just as easy as tapping the touch screen, but users should decrease the volume when switching between OP and tube options, as a loud pop will occur when activating. A significant improvement in microphonic noise suppression gives the 4000T a far quieter external profile. Speaking of previous models, the 4000T also adopts features and specs of the standard 4000, including its Octa Core CPU, High Driving Mode, enhanced signal alignment, and advanced DAR.
User Interface
Like the standard 4000, the 4000T utilizes a full Android OS. The DAP comes preloaded with Tidal and the Google Play Store, giving users immediate access to a popular hi-fi streaming option alongside simplifying the process of downloading others. Alongside the aforementioned tube settings, the 4000T offers a band
Visually, the 4000T’s UI works to actualize the build’s futuristic image. The volume display’s intersecting lasers emulate the shell’s geometric divots. Additionally, settings for the tube controls provide a visual of the tube’s influence, glowing a hotter red the more they are leaned on. This scale also affects the glowing tubes on the back. In all, this serves to create a digital device which feels like an analog machine, cleverly parallel to the audio technology inside.
Battery
Running the DAP with no enhancement features nets ten hours of playback, giving ample battery life for any extended listening session. Charging the 4000T to full takes five hours, which is slightly inconvenient but entirely understandable for a device so technologically dense.
Sound
The 4000T follows the rest of its line by leaning towards precision, though the tube settings provide a satisfying warm underbelly. I think the only thing I’d describe as truly clini cal with this DAP is the sheer potential for customization, giving those who love the overall tube sound the avenues to specialize it even more to their tastes.
Starting with the Sennheiser HD 600, its neutral signature unveiled the aforementioned warmth. It was here I tested and experimented with the different tube settings, finding each to add distinct properties to the sound. For the 600’s, I found Triode Mode gave its natural personality a relaxing polish. Moving to the opposite direction with the Campfire Bonneville, the 4000T was able to retain the IEM’s more expressive sound signature whilst pulling back a bit of the brightness. Bass was weighty yet nuanced, helped further by the higher output Pentode Mode. Dan Clark Audio’s E3 was a strong closer, utilizing the power of the 4000T to broaden its already impressive closed-back scope. The 4000T does not intrude on the statements these individual headphones make, rather it unleashes them to pursue something greater.
Although I don’t intend to brand the 4000’s tube counterpart as a pure rock machine, using the 4000T’s tube alterations to review Rush’s discography for their tour was nothing short of bliss. Fuzzy guitars developed a level of polish I thought impossible in such a chaotic effect. Intricate percussion was decipherable to the finest detail, and bass was bouncy and rewarding without overtaking the mix. The synths on “Subdivisions” gain a controlled explosiveness that truly feels analog. Even as I continue to prepare for my Montreal date, I feel as though I already saw them through the 4000T.
Summary
Astell & Kern’s newest addition to the to the A&ultima is a gargantuan stride in analog sound. The innovative tube structure, expansive customization tools, and pristine sound quality make the 4000T a title contender amongst its impossibly heavy weight class. The DAP encourages your devices by lining natural sound with additional clarity and smooth connection, all within a compact and easy to use package. For somebody looking to swing for the audio fences as far as price is concerned, the 4000T is absolutely a home run.
The Astell & Kern SP4000T is available at Audio46.
