Matrix Audio NA-1

Matrix Audio NA-1, Class A headphone amplifier

When Matrix Audio decided to design a desktop Hi-Fi system with separate components, the manufacturer made a clear technical choice: pure Class A discrete amplification, with no switching, no switching transistors. The NA-1 is the amplification component in this N series, alongside the NT-1 (network transport) and the ND-1 (converter). A 6 kg block of CNC-machined aluminum, with four independent amplification stages under the hood and an 80-watt toroidal transformer.

A layered design to isolate the stages

The NA-1 adopts an unconventional vertical internal structure. The preamp circuit, linear power supply, and capacitor bank occupy the lower PCB; the headphone amplification stage is placed above, on a separate PCB. This physical layout isolates the voltage and current amplification sections, limits interference between them, and optimizes heat dissipation. The heat generated by Class A (35W at idle) naturally rises toward the upper and side ventilation grilles.

The aluminum chassis is CNC-machined from a solid block. The feet incorporate MA-DAMPER PRO dampers, developed in collaboration with Audio Bastion, which combine five materials (aluminum, stainless steel, rubber, isolation balls, and composite cork) to filter mechanical vibrations.

Power and control for any type of headphone

The figures speak for themselves. In balanced output, the NA-1 delivers 18 watts into 33 ohms, 4.5 watts into 300 ohms, and 2.3 watts into 600 ohms. In single-ended mode, it drops to 7 watts into 33 ohms. Output impedance remains below 1 ohm, ensuring a high damping factor that allows the amplifier to control transducer movement with authority, including the most current-hungry planar headphones.

Two gain modes are independently available for the headphone output (+17dB / +23dB) and for the preamp output (+15dB / +21dB). High headphone gain mode increases voltage swing for high-impedance models. High preamp gain mode is useful with active speakers or a power amplifier with low input sensitivity.

A black background and an oversized power supply

The power supply is built around an 80W encapsulated (“potted”) toroidal transformer, a technique that reduces mechanical vibrations and electromagnetic radiation. A metal shield surrounds the whole assembly. The filtering capacitors total 39,000 µF of capacitance, distributed across independent rails for the preamp and the power stage.

The stated measurements reflect this meticulous design: signal-to-noise ratio of 120 to 123 dB depending on gain (A-weighting) for the headphone output, total harmonic distortion + noise below 0.0007%. Channel separation reaches -134 dB in balanced mode and -126 dB in single-ended mode.

A motorized old-school potentiometer

Matrix Audio chose a motorized ALPS Type 27 quadruple potentiometer for volume control. This analog component, prized for its precise channel matching, can be operated manually or via infrared remote control. In the latter case, the front-panel knob physically turns, a retro touch that is more than cosmetic: it lets you know the volume level at a glance.

The included remote control (RM4E) provides access to all functions: volume, mute, input selection, output selection, gain mode. Five remote control addresses can be programmed to avoid conflicts if several Matrix devices are used together.

Complete connectivity for flexible integration

On the input side, the NA-1 accepts one balanced source via XLR and two single-ended sources via RCA. All three inputs can be switched from the front panel or the remote control.

On the headphone output side, three connectors are available simultaneously: 4-pin XLR, 4.4 mm Pentaconn, and 6.35 mm jack. No need to choose or unplug one headphone to use another.

The preamp outputs (XLR and RCA) allow connection to a power amplifier or active speakers. The NA-1 can also combine headphone output and preamp output in parallel, convenient for switching between headphones and speakers without changing cabling.

The trigger system (12V input and output) allows synchronized power on/off with other compatible devices.

Sound signature and uses

The tonal behavior of the NA-1 reflects its Class A design: refined and airy highs, dense and textured mids, firm and articulate bass. The stereo image unfolds broadly, with precise placement of sound sources. Class A brings that characteristic fluidity, without the hardness sometimes heard in the most dynamic passages with other topologies.

This signature is equally suited to extended listening and critical analysis of mixes or masters. The mute function instantly cuts the signal, useful in the studio.

Technical Specifications

Pure Class A Amplification

• Fully discrete pure Class A architecture
  • Continuous amplification, with no switching
  • 4 independent modules in symmetrical configuration
  • Extremely low distortion
• Lively, dense, and natural sound reproduction
  • Absolute fluidity
  • Rich and organic timbre
  • Compression-free dynamics

Power and control

• Output power: up to 18 W balanced
• Ultra-low output impedance: < 1 Ω
• Dual independent gain modes
• Universal compatibility: high-impedance headphones, demanding planar models, audiophile flagships
• Operation with authority, stability, and precision

Soundstage and imaging

• Multilayer and symmetrical architecture
  • Exceptional channel separation
  • Reduced interference
  • Holographic stereo image
• Listening performance
  • Wide and deep soundstage
  • Ultra-precise instrument placement
  • Perfectly legible micro-details

Power supply

• Shielded toroidal transformer: 80 W
• Filtering capacity: 39000 µF
• Separate power supply for each stage
• Absolute black background
• No electrical pollution
• Intact dynamics, even at low volume

Analog volume control

• Motorized ALPS Type 27 potentiometer
  • Smooth and precise adjustment
  • Remote control with physical knob rotation
• Elegant and tactile interaction

Connectivity

• Inputs
  • 1 × balanced XLR
  • 2 × RCA
• Headphone outputs
  • 4-pin XLR
  • 4.4 mm balanced
  • 6.35 mm
• Preamplifier outputs
  • XLR
  • RCA
• Total versatility, from headphones to active speakers

Mechanical and thermal design

• Internal architecture in separate layers
• Optimized heat dissipation
• Advanced mechanical isolation (MA-DAMPER PRO)
• Stable, silent, and durable performance

Design and manufacturing

• CNC-machined aluminum chassis
• Premium minimalist finish
• Matrix Audio aesthetic DNA

Sound signature

• Typical Class A reproduction
  • Highs: refined, open, never aggressive
  • Mids: rich, textured, embodied
  • Lows: deep, firm, and articulate
• Perfect balance between precision and musicality

Power and consumption

• Voltage: 100–240 V AC
• Standby power consumption: < 1 W
• Operating power consumption: 35 W
• Maximum power consumption: < 80 W

Dimensions and weight

• Width: 330 mm
• Depth: 275 mm
• Height: 97 mm
• Weight: 6.16 kg

Box contents

• Remote control
• Power cable
• User manual
• Warranty card

General information

The NA-1 is a pure Class A desktop headphone amplifier and preamplifier designed by Matrix Audio. Paired with the NT-1 (network transport) and the ND-1 (digital-to-analog converter), it becomes the heart of an ultimate and scalable desktop Hi-Fi system.