PB6

Four Military-Grade JAN6418 Tubes | Fully Powered Tubes for Maximum Performance
The PB6 utilises four military-grade JAN6418 directly heated pentode vacuum tubes manufactured by Raytheon within a fully balanced 4-channel amplification architecture. iBasso designed the anode power supply to deliver 22.5V, providing excellent headroom and strong dynamic performance. All vacuum tubes are carefully tested and matched using APX555 audio measurement equipment to ensure channel consistency and exceptional sound quality. The fully balanced design delivers a rich, warm tube character with a natural listening experience.

Tube + Class AB Dual Output Modes | Switch Between Tube Warmth and OP-AMP Clarity
The PB6 supports both Tube and Class AB output modes. In Tube mode, the four JAN6418 tubes act as the amplification stage, producing a smooth, rich and warm presentation with the distinctive characteristics of vacuum tube sound. In Class AB mode, the PB6 employs a classic OP-AMP + BUF headphone amplifier circuit using four BUF634A buffers for current amplification, delivering enhanced resolution and excellent dynamic range.

8.4V High-Voltage Battery Pack | Higher Efficiency and Cleaner Power
The PB6 uses an 8.4V high-voltage polymer battery pack, significantly improving power efficiency and transient response. Compared to conventional single 3.7V battery designs, the higher-voltage configuration greatly reduces ripple interference generated during DC-DC conversion, resulting in cleaner and more stable power delivery. This allows musical detail and dynamic range to be reproduced with greater accuracy and realism.

12V External Power Supply | Desktop-Grade Performance
The PB6 supports an external 12V DC power supply, enabling a voltage swing of up to 24V. When connected to external power, output increases to 2300mW + 2300mW at 32Ω, fully unlocking the amplifier’s driving capability. This allows the PB6 to power demanding full-size headphones with performance approaching high-quality desktop headphone amplifiers.

High-Precision 4-Channel NJW1195A Volume Control
The PB6 features the NJW1195A high-precision 4-channel volume control IC, offering fine 0.5dB adjustment steps. This hardware-based volume control enables precise adjustment while helping reduce background noise for a cleaner listening experience. It also eliminates the channel imbalance commonly associated with traditional analogue potentiometers at low volume levels, ensuring accurate left/right channel balance throughout the entire volume range.

Selectable High and Low Bandwidth Modes | Tailor the Sound to Your Preference
The PB6 offers both high-bandwidth and low-bandwidth headphone output modes. High-bandwidth mode delivers faster transient response, greater control and improved resolution, while low-bandwidth mode creates a softer, warmer sound signature. This flexibility allows listeners to tailor the presentation to their personal preferences.

PORON Suspension Damping | Suppresses Microphonic Effects
To minimise microphonic effects, all four tubes are suspended using PORON damping material, isolating tube vibration from affecting sound quality. In addition, a metal mesh shielding cover is fitted around the tubes to reduce external electromagnetic interference.

3.5mm Single-Ended and 4.4mm Balanced Input / Output
The PB6 provides both 3.5mm single-ended and 4.4mm balanced inputs and outputs. This flexible design allows sources with only a 3.5mm output to connect to the PB6 while benefiting from 4.4mm balanced headphone output, offering increased resolution and stronger dynamic performance associated with balanced amplification.