Cayin N3 Ultra NOS Vacuum Tube Digital Audio Player

The Cayin N3 Ultra is a music player with real valves: the successor to Cayin’s N3Pro, it puts two military-grade Raytheon JAN6418 NOS (new old stock) vacuum tubes on every analogue output. Choose Classic tube, Modern tube or solid-state sound on the headphone and line outputs alike, with the same output power in every timbre, up to 600mW balanced. Dual AK4493S DACs, a 10-band parametric EQ and a streamlined, audio-only Android system complete a compact 204g player, first shown at CanJam New York 2024.

The beauty of simplicity

The N3 Ultra runs a fully customised operating system, streamlined to focus solely on audio, for an authentic, minimalist experience built around the sound of its vintage tubes. Cayin’s DTA system bypasses Android’s sample-rate conversion for lossless playback up to 32-bit/768kHz and DSD512.

Military-grade NOS tubes on every output

Two Raytheon JAN6418 military-grade miniature direct-heated pentodes serve both the 3.5mm and 4.4mm outputs, for headphones and at line level, each able to produce a tube or solid-state timbre. Tube timbres on the line outputs are new compared with the N3Pro.

Shock absorption and suspension

Cayin’s in-house mechanical and circuit upgrades keep microphonics down. A custom-moulded silicone housing holds and shields each tube, and pairs of suspension pins designed into the CNC aluminium frame let the JAN6418 hang vertically, giving multi-directional stress relief for its filament. A measured amount of inter-stage negative feedback limits the closed-loop gain for stability, and a FET controls the tube’s power supply to keep the filament current steady.

Classic, Modern or solid-state

Rather than using the pentode as a simple buffer, the N3 Ultra uses Cayin’s third-generation tube technology in a two-stage timbre circuit: the JAN6418 is connected as a low-gain voltage amplifier, followed by a FET buffer for drive. Changing how the tube’s screen grid is connected applies local feedback through it, giving two distinct styles of response, distortion and output impedance. Pick from the pull-down menu: Classic tube, lush, warm and full-bodied with rich overtones; Modern tube, with a lively soundstage, well extended and impressively linear; or solid-state.

Dual AK4493S DACs and precision parts

Two AK4493S DACs work in mono mode for a fully differential output, with independent DAC chips and analogue circuits for each channel to minimise crosstalk and improve clarity and stereo separation. An FPGA re-clocks, de-jitters and re-shapes the data, timed by two Accusilicon AS318 femtosecond oscillators with ultra-low phase noise (−100dBc) for accurate conversion with much lower jitter. Volume is set by JRC’s NJW1195A, a low-noise, low-distortion resistance-ladder analogue volume chip common in audiophile pre-amps, controlling all four channels precisely with little power; the headphone stage uses four low-noise op-amps as two amplifiers in parallel.

A versatile source with dual line out

Besides a dedicated 3.5mm line out, the 4.4mm balanced output can be set as a headphone or line output. The line outputs are clean and unamplified, at a fixed level that bypasses the volume control and headphone amplifier, to feed a portable or desktop headphone amplifier or an integrated amplifier at home, with three levels: 2.1V, 1.6V or 1.0V from 3.5mm and 4.2V, 3.2V or 2.0V from 4.4mm. Over USB-C the N3 Ultra is also a digital transport, with USB audio output and S/PDIF coaxial embedded in the USB-C socket, and a USB DAC for a computer or phone.

A 10-band parametric EQ

A 10-band parametric EQ designed for the N3 Ultra offers almost unlimited tuning, so you can fine-tune each pairing with your in-ear monitors to your own taste.

Battery, screen and handling

A 3.85V 4,500mAh battery and carefully tuned power management give up to 11.8 hours from the 3.5mm output in solid-state timbre, or 7.6 hours from the 4.4mm output with tubes, and QC3.0 charges it from 20% to 80% in about an hour. A 4.1-inch 720 × 1280 touchscreen responds quickly, a physical knob and buttons cater to those who prefer them, and at 204g the N3 Ultra is sized for one-handed use and pockets. Store music on a microSD card up to 1TB, or add USB drives and card readers through OTG.

Good to know

• It has no Wi-Fi or Bluetooth: play music from microSD, USB storage, or use it as a USB DAC.
• For fast charging use a QC3.0 charger; PD2.0 fast charging is not supported.
• USB DAC mode needs an OTG cable to connect to your source, and Windows computers need Cayin’s driver.
• In the box: N3 Ultra, silicone protective case, tempered glass screen protector, USB-C cable and quick guide.