The Beauty of Simplicity Vintage Tubes, Cutting-edge Sound The N3Ultra uses a fully customised operating system streamlined to focus solely on audio applications. Creating a device that provides an authentic and minimalist experience, allowing users to enjoy the new auditory pleasure brought by the vintage JAN6418 vacuum tubes. Military-grade NOS Tubes Applicable to All Analog Outputs Equipped with two Raytheon JAN6418 military-grade miniature direct-heated pentode NOS vacuum tubes. The N3Ultra offers both single-ended 3.5mm and balanced 4.4mm Headphone and Line level analogue outputs, each capable of producing both vacuum tube and solid-state timbre. High-Quality DAC Featuring dual AK4493S DACs in fully differential output mode, the N3Ultra ensures superior audio clarity and stereo separation. Independent DAC chips and analogue audio circuits for each channel minimize crosstalk, delivering an immersive listening experience. Shock Absorber and Suspension, In-house developed mechanical and circuitry upgrades minimize microphonic effects Custom-moulded shock absorption Silicon housing to hold and shield the JAN6418 vacuum tube. Designed pairs of suspension pins into the CNC aluminium frame of N3Ultra, the JAN6418 hangs vertically with a suspension effect. Integrated the miniature vacuum tube with the body frame, achieving multi-directional stress relief for the tube's filament. Enhance stability by Introduce an appropriate amount of inter-stage loop NFB to inhibit the closed-loop gain Employ FET to control the power supply of the vacuum tube and stabilize the working current of the tube filament Classic | Modern | Solid-State - Up to Three Timbres in All Analog Outputs Instead of using the miniature pentode tube as an audio buffer, N3Ultra adopts Cayin's Gen3 vacuum tube technology and employs a two-stage timbre circuit for JAN6418: First Stage: connect the JAN6418 as a low-gain voltage amplifier Second Stage: a FET buffer is added to improve the driving capability of the timbre circuit By varying the connection method of the screen grid of the pentode tube, the JAN6418 incorporates local NFB through the screen grid, resulting in two distinct styles of circuit response, distortion, and output impedance. Fun and Versatile Portable Source - Dual Line Out On top of a dedicated 3.5mm single-ended line out, the 4.4mm balanced output can be configured into Phone out or Line out. Maximum compatibility with configurable output levels: • 3.5mm: 2.1V (High), 1.6V (Mid), 1.0V (Low) • 4.4mm: 4.2V (High), 3.2V (Mid), 2.0V (Low) Enable users to connect the N3Ultra to a variety of portable, desktop and home audio devices. Clean and Unamplified Line Out is a fixed voltage line level output bypassing volume control and headphone amplification, serving as a high-quality source for headphone amplifiers (portable or desktop) and integrated amplifiers in home audio systems Applicability of Tube Timbers Solid-state, Classic tube and Modern tube timbres are available to all analogue outputs, including 3.5mm and 4.4mm headphone and line output options. Customizing with Parametric EQ - Unlocking Numerous Mix and Match Synergy A 10-band parametric EQ is specifically designed for the N3Ultra, offering unlimited sound tuning possibilities. Allows detailed customization of IEM pairing according to listening preferences, creating a personalized audio experience tailored to the user. Fast Charging Long Playback Duration Hefty 3.85V 4500mAH Lithium battery with a carefully tuned power management system. Continuous playback up to 11.8 hours with 3.5mm single-ended IEM in solid-state timbre, and 7.6 hours with 4.4mm balanced IEM in vacuum tube timbre. Recharge quickly with QC3.0, it can charge up your DAP from 20% to 80% in around 1 hour