Astell&Kern A&ultima SP4000 Portable Music Player

🧾 Overview

The Astell&Kern A&ultima SP4000 is a no-compromise flagship portable music player crafted from 904L stainless steel. Featuring a true quad-DAC architecture (4× AK4191 + 4× AK4499EX), octa-core processing, and a 6″ 2K display, it delivers reference-grade sound with massive headroom and ultra-low noise. Designed for connoisseurs, SP4000 elevates both wired and wireless listening to a new level.

✅ Key Features

• ✅ Real Quad DAC: 4× AKM AK4191 + 4× AKM AK4499EX with Octa Audio Circuit Architecture :contentReference[oaicite:1]{index=1}
• ✅ PCM up to 32-bit/768 kHz & native DSD512; bit-to-bit playback :contentReference[oaicite:2]{index=2}
• ✅ 904L stainless-steel chassis, ceramic rear; premium Perlinger shrunken calf leather case included :contentReference[oaicite:3]{index=3}
• ✅ Powerful output: up to 8.2 Vrms balanced / 4.1 Vrms unbalanced (no load) :contentReference[oaicite:4]{index=4}
• ✅ 6″ 2160×1080 touch display, octa-core CPU, dual-band Wi-Fi, BT 5.0 (LDAC/aptX HD/LHDC) :contentReference[oaicite:5]{index=5}
• ✅ Enhanced ESA timing, ultra-low-noise LDO, 99.9% copper shielding (noise suppression) :contentReference[oaicite:6]{index=6}

📦 What’s in the Box

• 📦 Astell&Kern A&ultima SP4000 player
• 👜 High-End Perlinger shrunken calfskin leather case
• 🔌 USB-C → USB-C cable (1 m)
• 🛡️ 3× screen protectors
• 📖 Quick start guide & warranty info

Box contents confirmed by multiple trusted retailers/reviews. :contentReference[oaicite:8]{index=8}

🔄 Compatibility

✔ Works with balanced (4.4 mm) and unbalanced (3.5 mm) headphones; optical S/PDIF via 3.5 mm.
✔ USB-DAC mode for Windows/macOS; USB-C audio out to external DACs.
✔ Wireless playback via LDAC/aptX HD/LHDC over Bluetooth; dual-band Wi-Fi for streaming apps. :contentReference[oaicite:9]{index=9}

📦✈️ Shipping & Returns

• 📦 Insured worldwide delivery
• 🔄 14-day return policy
• 🛡️ 2-year EU warranty

📝 Reviews

• 🔹 Audio46 — unboxing confirms leather case, USB-C↔USB-C cable, protectors, docs; praises dynamics and refinement. :contentReference[oaicite:10]{index=10}
• 🔹 Moon Audio — highlights Octa Audio Circuit, ESA timing and ultra-low-noise regulation; strong shielding. :contentReference[oaicite:11]{index=11}
• 🔹 Wallpaper* — notes 6″ 2160×1080 display, 904L steel, Perlinger case, and Android app access. :contentReference[oaicite:12]{index=12}

⚠️ Warning

⚠️ Warning: Extended sessions with the SP4000 may trigger spontaneous library “remasters,” late-night firmware checking, and an irresistible urge to upgrade every pair of headphones you own.