Cayin has introduced the RU9, a groundbreaking portable DAC and headphone amplifier that marks a new chapter in the fusion of analog warmth and digital precision. At the heart of this engineering marvel lies the Korg NuTube 6P1, a modern vacuum tube designed to bring tonal richness and warmth to portable audio. Combined with meticulous hardware design, the RU9 delivers an unprecedented level of performance and versatility.

The RU9 features a dual DAC architecture with separate AK4493SEQ chips for each channel, enabling ultra-high-resolution audio decoding. It supports PCM up to 32-bit/768kHz and DSD formats up to DSD512, processed through an advanced XMOS XU316 USB chipset with 16 cores. Amplification is equally sophisticated, utilizing a fully balanced four-channel circuit that includes six Toshiba 2SK209 JFET transistors and low-noise OPA1662 operational amplifiers for precision and clarity. This design produces dynamic, distortion-free sound through both single-ended (3.5mm) and balanced (4.4mm) headphone outputs.

One of the standout features of the RU9 is its timbre customization. With three distinct profiles—Classic Tube, Modern Tube, and Solid-State Transistor—it allows listeners to tailor the sound to their preferences. Classic Tube delivers the signature warm, saturated sound characteristic of vacuum tubes, while Modern Tube offers a cleaner, slightly brighter tonality. The Solid-State mode emphasizes neutrality and fast transients, driven by the OPA1662 amplifier circuitry. This versatility ensures the RU9 can adapt to a wide variety of musical genres and headphones.

For audiophiles seeking even more power, the RU9 introduces a Dynamic DC Hyper Mode, pushing its output to an impressive 1000mW at 32Ω impedance when externally powered. This mode enhances dynamics, transparency, and overall detail, making it ideal for demanding headphones or critical listening sessions. Additionally, the onboard battery offers up to 4.7 hours of portable operation, while Bluetooth connectivity via Qualcomm’s QCC5125 chipset supports high-definition codecs like LDAC, AptX HD, and AptX LL for wireless listening.

Crafted with precision, the RU9 features a CNC-machined aluminum chassis that balances durability and portability. A magnetic rear panel allows easy attachment to smartphones or other devices, while its compact design, weighing only 150g with a 15mm thickness, ensures convenient everyday use. The display provides real-time information, including volume, profile mode, connection type, and gain level, making operation intuitive.

The Cayin RU9 sets a new benchmark for portable audiophile equipment with its unique integration of tube and solid-state technologies, high-resolution decoding capabilities, and customizable sound profiles. Priced at $449.99, it offers a compelling mix of innovation and performance for discerning music enthusiasts.

Cayin has introduced the RU9, a groundbreaking portable DAC and headphone amplifier that marks a new chapter in the fusion of analog warmth and digital precision. At the heart of this engineering marvel lies the Korg NuTube 6P1, a modern vacuum tube designed to bring tonal richness and warmth to portable audio. Combined with meticulous hardware design, the RU9 delivers an unprecedented level of performance and versatility.

The RU9 features a dual DAC architecture with separate AK4493SEQ chips for each channel, enabling ultra-high-resolution audio decoding. It supports PCM up to 32-bit/768kHz and DSD formats up to DSD512, processed through an advanced XMOS XU316 USB chipset with 16 cores. Amplification is equally sophisticated, utilizing a fully balanced four-channel circuit that includes six Toshiba 2SK209 JFET transistors and low-noise OPA1662 operational amplifiers for precision and clarity. This design produces dynamic, distortion-free sound through both single-ended (3.5mm) and balanced (4.4mm) headphone outputs.

One of the standout features of the RU9 is its timbre customization. With three distinct profiles—Classic Tube, Modern Tube, and Solid-State Transistor—it allows listeners to tailor the sound to their preferences. Classic Tube delivers the signature warm, saturated sound characteristic of vacuum tubes, while Modern Tube offers a cleaner, slightly brighter tonality. The Solid-State mode emphasizes neutrality and fast transients, driven by the OPA1662 amplifier circuitry. This versatility ensures the RU9 can adapt to a wide variety of musical genres and headphones.

For audiophiles seeking even more power, the RU9 introduces a Dynamic DC Hyper Mode, pushing its output to an impressive 1000mW at 32Ω impedance when externally powered. This mode enhances dynamics, transparency, and overall detail, making it ideal for demanding headphones or critical listening sessions. Additionally, the onboard battery offers up to 4.7 hours of portable operation, while Bluetooth connectivity via Qualcomm’s QCC5125 chipset supports high-definition codecs like LDAC, AptX HD, and AptX LL for wireless listening.

Crafted with precision, the RU9 features a CNC-machined aluminum chassis that balances durability and portability. A magnetic rear panel allows easy attachment to smartphones or other devices, while its compact design, weighing only 150g with a 15mm thickness, ensures convenient everyday use. The display provides real-time information, including volume, profile mode, connection type, and gain level, making operation intuitive.

The Cayin RU9 sets a new benchmark for portable audiophile equipment with its unique integration of tube and solid-state technologies, high-resolution decoding capabilities, and customizable sound profiles. Priced at $449.99, it offers a compelling mix of innovation and performance for discerning music enthusiasts.