‘More drivers than a Formula 1 grid’: A&K brings Christmas early for audiophiles with its new premium audio player with built-in quad vacuum tubes plus new ‘Tribrid’ 9-driver IEMs to pair with it

Astell & Kern unveils a new portable Hi-Res Audio player and earphones
The SP4000T audio player has four more vacuum tubes
Clarus in-ear monitors offer nine drivers in ‘Tribrid’ design

Astell & Kern has just revealed its next two major releases, and while we’re missing practical details like price and availability just yet, as well as a few key details and specs, we’re very interested in what has been teased so far.

The two products are the A&K SP4000T, a premium audio player with some exciting amplification, and the Clarus, which are new in-ear monitors with more drivers than a Formula 1 grille. Let’s take a look at both of them.

Clarus in-ear monitors

(Image credit: Astell&Kern)

The Astell & Kern Clarus are the brand’s latest wired IEMs, following the Luna that was unveiled just under a year ago as its fourth pair of buds in this product line.

The SP4000T player

Two A&K SP4000T on a desk next to some Luna IEMs.

(Image credit: Astell & Kern)

The major new release is the SP4000T. This is the long-awaited successor to the SP3000T, which we gave a glowing five-star review, and it justifies itself as a new model with clear upgrades.

The real feature of the SP4000T is that it has four built-in vacuum tubes, arranged in a quad formation, to allow a warm sound profile in a greater number of variations than before.

We’ve seen some portable audio players with dual vacuum tubes – such as the SP3000T or the Shanling M8T, both of which used the same JAN6418 tubes that the SP4000T does – but using four gives an even greater amount of versatility than two would.

This number allows tubes dedicated to both left and right channels, and in combination with amp and tube current adjustments, A&K promises three main sound profile modes: ‘Triode’ for rich harmonics and natural acoustics, ‘Pentone’ for power and ‘Ultra Linear’ which mixes the two.

Another upgrade to the A&K SP4000T is the improved five-stage anti-microphonic architecture, which goes further in stopping potential distortion in the vacuum tubes caused by them being in a portable unit (tubes have historically not performed very well).

It looks like A&K is also opening up to more wireless music with upgraded support for LDAC and aptX Adaptive, and a new mode also lets you use the unit as a wireless Bluetooth DAC for your smartphone. Not only that, but a new dual Wi-Fi antenna means you can stream music more reliably.

Otherwise, you’re looking at a digital audio player running Android 15 that comes in either stainless steel or copper models, and also comes with a leather travel case. It comes with 256 GB of storage as standard, but can be expanded up to 1.5 TB via microSD.

While the exact price of the Astell & Kern SP4000T isn’t known yet, I’m guessing it could cost more than its predecessor’s price of $2,999 / £3,199 / AU$5,299 – but if it performs better, it’ll be worth a spot on our list of the best Hi-Res Audio players.