xDuoo MT-04 Balanced Hybrid Tube Headphone Amplifier

xDuoo MT-04 Balanced Hybrid Tube Headphone Amplifier

The xDuoo MT-04 pairs dual 6H3 vacuum tubes with a transistor-based Class A output stage, combining tube-stage character with solid-state drive in a compact desktop headphone amplifier. Balanced and unbalanced connections, adjustable gain and a transparent-panel design make it a versatile addition to a wired listening setup.

Key Features

• Two 6H3 vacuum tubes in the preamplifier stage.
• Hybrid tube-transistor design with Class A current amplification.
• Balanced headphone output rated at 2200mW into 32Ω.
• RCA analog, XLR balanced and 4.4mm balanced inputs.
• 4.4mm balanced and 6.35mm unbalanced headphone outputs.
• Selectable +12dB / +18dB gain.
• ELNA audio coupling capacitors and Rubycon filter capacitors.
• Relay protection with a 30-second power-on delay.
• Aluminum alloy enclosure with clear acrylic front and rear panels.

Tube Warmth Meets Transistor Control

The dual 6H3 tubes provide the preamplification stage, with manufacturer-described full midrange, smooth vocals and gentle treble. The transistor power stage provides current drive and control for bass impact and dynamic passages. This hybrid architecture is intended to balance an inviting tonal presentation with responsive headphone amplification.

Connect an analog source, choose the appropriate gain and settle into an album: the MT-04 offers tube-based listening character without requiring a large desktop footprint. Actual sound and listening level depend on your headphones, source and volume setting.

Class A Output Stage

The transistor-based Class A current-expansion circuit is designed for transient response and control. The balanced output provides up to 2200mW into 32Ω, with separate manufacturer ratings for loads up to 600Ω. Impedance alone does not determine headphone compatibility; sensitivity and required listening level also matter.

Balanced & Unbalanced Connections

Choose RCA analog, XLR balanced or 4.4mm balanced input to match your source. Front headphone connections include 4.4mm balanced and 6.35mm unbalanced outputs. The supplied figures specify higher channel separation and signal-to-noise performance for the balanced output.

This is an analog headphone amplifier, not a DAC. Bluetooth and a built-in battery are not included.

Adjustable Gain & Ground Terminal

An external switch selects +12dB or +18dB gain for different listening requirements. Start with low gain and a low volume setting, particularly with sensitive earphones. The external grounding post is intended to help address grounding-related hum or static interference when correctly connected; it is not a guarantee that all system noise will be eliminated.

Audio-Grade Components & Relay Protection

ELNA coupling capacitors and Rubycon filter capacitors support the analog circuit. The protection system provides a 30-second power-on delay for tube warm-up and is designed to reduce switching pops, with overload and short-circuit protection.

Aluminum Body with Clear Panels

The aluminum alloy chassis helps shield the electronics from electromagnetic interference, while clear acrylic front and rear panels reveal the internal components. At 13.6 × 11.0 × 8.1cm and approximately 0.61kg, the MT-04 fits compact desktop systems.

General Specifications

Headphone Output Power

Output Performance

All performance figures are manufacturer-provided. Measurement conditions were not specified in the supplied text and may affect results.

What's in the Box?

• 1 × xDuoo MT-04 headphone amplifier.

The complete accessory bundle was not specified in the supplied information. Please confirm the included power adapter, regional mains plug and other accessories before ordering if required.

Before You Listen

Use a power supply matching the specified DC 12V / 2A requirement and follow the manufacturer's instructions. Allow the startup delay to complete before listening. Keep the unit ventilated, avoid touching hot tubes during use and switch off the amplifier before changing connections.

Manufacturer Product Details