Astell & Kern is expanding its A&ultima line of flagship portable players with the launch of the SP4000T. It arrives alongside a new pair of in-ear monitors, the Clarus. Both are set to make their debut at this year’s Vienna High End Show (4th June to 7th June).
Astell & Kern’s new A&ultima SP4000T teases a combination of “cutting-edge digital audio” with “classic analogue technology” thanks to its harnessing of vacuum tube amplification.
The new player uses independent dual-tube structures dedicated to left and right channels, the same separated configuration normally associated with classic tube amps. Further, dual flagship AK4499EX DACs and dedicated signal processors across each channel promise a “deep, refined experience” and enhanced “clarity, depth and sonic purity”.
The SP4000T offers three distinct tube sound modes, each of which has its own unique sonic signature. ‘Triode Mode’ emphasises rich harmonics and a warmer, more immersive presentation, whereas 'Pentode Mode' focuses more on dynamic impact and a cleaner, more energetic presentation.
For a third way, ‘Ultra Linear Mode’ promises a blend of the tonal richness of ‘Triode’ with the power and control of the ‘Pentode’ setting.
Astell & Kern’s valve-sporting PMP supports PCM files up to 32-bit/768kHz alongside DSD512, as well as 256GB of internal memory which can be expanded out to 1.5TB via the included microSD port.
Bluetooth codec support is provided via aptX Adaptive and LDAC codecs, while a ‘Bluetooth Sink’ mode allows the SP4000T to function as a Bluetooth DAC for external devices.
The new A&K features a 6-inch HD touchscreen display and is available in either a stainless steel or copper finish. Prices are yet to be confirmed, but considering the established SP4000 player launched at around £3999 / $4000, we doubt the tech-laden SP4000T will come particularly cheap.
Also arriving alongside the SP4000T portable music player are A&K’s latest in-ear monitors, the Clarus, which will be making their bow at this month’s High End Show in Vienna.
Acting as the latest addition to A&K’s high-end IEM series, the new in-ears are built around a 10-driver architecture, with a dynamic driver handling the low frequencies, an array of balanced armature drivers focusing on the mid-range and a host of MEMs units promising to “render the upper frequencies with exceptional precision”.
Again, no prices or official release date are currently available, but we’ll let you know as soon as we have official facts and figures.
We are heading to High End Vienna 2026 very soon, so we’ll be in the best position to give you the low down on everything being showcased, including A&K’s latest releases.
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