Astell&Kern unveils limited-edition copper-bodied portable premium music player and leather valet case

Luxury audio auteur Astell&Kern has expanded its flagship portable line-up with the A&ultima SP4000 Copper, a limited-edition version of its top-tier digital audio player, alongside the Collector’s Atelier, a premium leather valet case. 

The A&ultima SP4000 Copper sits at the top of Astell&Kern’s player hierarchy and shares the core architecture of the standard SP4000. That includes a quad-DAC configuration, an octa-circuit design and a fully balanced signal path, all intended to preserve signal integrity from digital source to analogue output.

The chassis is milled from 99.98 per cent pure copper, a material long valued in audio engineering for its conductivity and shielding properties, but rarely used at this scale due to its softness and tendency to oxidise.

Astell&Kern says the SP4000 Copper required a multi-layer stabilisation process and highly controlled machining to ensure durability and a consistent finish.

The SP4000 Copper is positioned as a limited-edition product for those who value both sound quality and material craftsmanship…

Astell&Kern A&ultima SP4000 Copper design

Those material choices are not purely cosmetic. Copper’s electrical characteristics are said to reduce internal noise and interference, contributing to a sound signature that emphasises natural tonal weight and low-level detail.

According to the company, the new player delivers authoritative bass, a dense and expressive midrange and treble that decays smoothly, aiming to present music as a cohesive, lifelike whole rather than a collection of Hi-Fi effects.

As with other A&ultima models, the physical interface, screen integration and control layout are designed to support focused listening, reinforcing the sense that this is a purpose-built audio instrument rather than a lifestyle gadget.

Collector’s Atelier valet case review

Alongside the player, Astell&Kern is shipping the Collector’s Atelier, a leather valet case designed to house your digital audio player, earphones and accessories.

The case is made using leather from Perlinger, a German tannery founded in 1864. The leather is premium male calf leather sourced from the Togo region of Africa and treated using Perlinger’s proprietary Shrunken leather process.

This technique avoids the use of heat, instead relying on a chemical shrinking process that preserves the leather’s natural grain and softness.

The result is a material that is supple, elastic and resistant to minor scratches, with a texture that develops greater depth and lustre over time.

The aim, according to the manufacturer, is to create an accessory that enhances the ownership experience and reflects the same attention to detail as the audio gear it houses.

The Astell&Kern A&ultima SP4000 Copper limited edition is priced at £3,999 ($4,499 / €4,699), the Collector’s Atelier valet case is also available, for £229 ($260).