Astell & Kern A&ultima SP4000 Copper Limited Edition Portable High-Resolution Digital Audio Player exclude from earzfit it is reflected in its

it is reflected in its design the earpieces are crafted from solid stable wood with natural grain wood

Sonics grainy

Good compatibility

OK0300PRO Optical cable

Astell & Kern A&ultima SP4000 Copper Limited Edition Portable High-Resolution Digital Audio Player exclude from earzfit it is reflected in itsLimited Edition Copper The A&ultima SP4000 Copper Limited Edition goes beyond a high end portable audio player. It represents the culmination of Astell&Kerns expertise in material engineering, precision manufacturing, and refined analog sound design. SP4000 Copper is the brands most definitive answer to a single question: how far can we go in the pursuit of the ultimate sound? Copper is theoretically one of the most ideal materials for audio, yet