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Cayin RU9 flagship USB DAC and headphone amplifier

AED 1,700

Ash

4.9

17 items live

Item Details

Age

1-6 months

Condition

Almost no noticeable problems or flaws

Warranty

No

Usage

Used only a few times

Posted on: 2nd November 2026

Description

The RU9 features a unique multi-powering architecture that directly impacts its amplification muscle:
• 🔋 Battery Mode: Uses the internal battery to avoid draining your smartphone. It outputs up to 620mW at 32Ω via the balanced port.
• 🔌 Bus Mode: Bypasses the battery to run directly off standard USB power.
• 🚀 Hyper DC Mode: When hooked up to an external power supply via its second USB-C port, it unleashes a massive 1000mW x 2 at 32Ω, essentially mimicking desktop-tier hardware.
• 🔋 Battery Life: Runs for roughly 3 to 4.7 hours on a single charge.

🎵 Triple-Timbre Options & Architecture

The digital-to-analog stage is handled by dual AK4493SEQ DAC chips combined with an XMOS XU316 processor, supporting up to 32-bit/768kHz PCM and native DSD512. The centerpiece is its triple-timbre physical switch or menu:
1. Classic Tube: Engages the Korg Nutubes without global feedback, resulting in a traditionally warm, musical, and mid-centric signature.
2. Modern Tube: Uses global feedback for lower distortion and noise, delivering hybrid technical precision blended with tube staging.
3. Solid-State: Bypasses the tubes entirely, using OPA1662 op-amps and Toshiba JFET transistors for a clean, fast, and neutral reference sound.

📲 Connectivity & Usability

• Physical I/O: Features a 4.4mm balanced output, a 3.5mm single-ended output (switchable between headphone and line-out), and a 3.5mm coaxial S/PDIF output.
• Dual USB-C Ports: One dedicated solely to audio data/USB power and another for independent fast charging/DC power input.
• Wireless: Operates as a Bluetooth 5.1 receiver supporting high-res codecs like LDAC and aptX HD.
• Form Factor: Weighs 150 grams and spans roughly the footprint of a deck of cards. It includes a 0.96-inch status display, side playback controls, and a smooth physical volume wheel.
• Shielding: Despite housing delicate vacuum tubes, it features robust structural cancellation against magnetic and radio (EMI) interference when attached to a phone