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In stock and available for immediate delivery.
The new RU9 offers exceptional features at an extremely fair price: It uses the same tubes as the "big" C9II. It also features two AKM DACs in mono configuration and a powerful output power of up to 1000mW per channel.
Best of all, it's compact and lightweight, can be connected directly to your smartphone, tablet, or computer, and offers absolutely stunning sound quality!
Reviews
"I found RU9 to be not just another dongle or a portable DAC/amp. As I mentioned earlier in the introduction of the review, this latest release from Cayin takes the concept of a “dongle” to a whole new level, making it a hybrid dongle. It is not only compact and MagSafe-ready to carry attached to your smartphone via a wired or wireless connection, but also adds NuTube into the equation with three different timbre settings to fine-tune the sound of RU9."
"The Cayin RU9 represents a bold experiment in portable audio design, successfully combining vacuum tube processing, magnetic smartphone integration, wireless connectivity, and substantial amplification in a device that challenges conventional category boundaries.
Sound quality, while not reaching the heights of premium portable or desktop equipment, provides a satisfying listening experience that justifies the device's existence. The tube processing adds genuine musical value, particularly in modern mode where technical performance remains strong while gaining harmonic richness. The amplification capability impresses across a wide range of headphones and IEMs, with the external power mode unlocking additional performance for demanding loads."
Review: Cayin RU9 Portable Tube DAC/Amp | The Headphone List
Highlights
Nutube 6P1 application
Supports both single-ended 3.5mm and balanced 4.4mm PO/LO outputs.
Each output can be switched between tube and solid state mode.
3 sound styles: Classic丨Modern丨SS
Classic:
- No global negative feedback; each stage uses local feedback.
- Tube amplification results in higher total harmonic distortion (THD).
- The rich harmonic texture creates a warm, nostalgic sound – the classic “tube sound”.
Modern:
- Introduces global negative feedback to define the overall gain.
- The THD is significantly reduced.
- Harmoniously clean, quieter background while maintaining the warmth of the tubes.
- Produces a sweet, clear and delicate modern tube sound.
semiconductor:
- Based on precisely tuned operational amplifier ICs and peripheral circuits.
- Offers neutral timbre, fast transients and high-precision audio reproduction.
- Ideal for listening to music with its original, unadulterated character.
Dual AKM AK4493SEQ DAC
Equipped with two AK4493SEQ DACs, each operating in mono mode. The left and right channels are decoded separately to reduce crosstalk and achieve better channel separation.
16-core XMOS XU316 processor
Uses the latest generation XMOS XU316 USB audio solution for powerful digital processing.
Triple power supply modes
The built-in 2000 mAh lithium battery allows for up to 4.7 hours of battery life. It also supports USB power from an external device (without recharging the battery) and an external DC power supply for higher Ausgangsleistung.Kompatibel with QC/PD fast charging.
Hyper Mode
A special feature for use with DC-powered headphones. Increases the static operating current and voltage for improved audio performance.
Balanced: 1000mW + 1000mW at 32Ω; 1170mW + 1170mW at 16Ω
Single-ended: 420 mW + 420 mW at 32 Ω; 610mW + 610mW at 16Ω
Magnetic back
- The magnetic back allows seamless attachment to smartphones.
- Included is a custom Cayin leather case – hand-stitched, made of supple leather, with precise cutouts and a magnetic back for a secure hold.
- With L-shaped USB cable, ergonomically angled to avoid hand strain.
Vibration isolation
- Custom-made anti-vibration system for the Nutube vacuum tube.
- Featuring a custom-made silicone housing on a flexible FPC circuit board and a vertical suspension system with pins to prevent microphony.
Elegant and compact
- CNC-machined one-piece metal housing.
- Weighs only 150 g and is 15 mm thick.
Well-thought-out details
- 0.96-inch color display with adjustable brightness.
- Knurled volume control with finely tuned resistance.
- Side-mounted multi-color indicator light for charge status and display of sample rate and format.
Diverse application possibilities
USB audio DAC
- Supports UAC1.0 (driverless) and UAC2.0 modes.
- Compatible with smartphones, computers, digital audio players, tablets and game consoles.
S/PDIF input/output
- Uses Qualcomm QCC5125 for high-resolution Bluetooth transmission.
- Supports LDAC and other HD Bluetooth codecs.
