NAT Audio — Amplifiers
Single Evo Vacuum Integrated Tube Amplifier
Pure class A triode performance with unprecedented signal transparency.
The Single Evo represents a masterclass in minimalist engineering, stripping away every non-essential passive component to allow the musical signal to flow without obstruction. By eliminating coupling capacitors, chokes, and inter-stage transformers from the signal path, NAT Audio has created an integrated amplifier of startling transparency and immediacy.
Positioned as the evolution of a decade-long pursuit of the perfect integrated platform, the Single Evo introduces the proprietary Linear Field output transformer. This breakthrough technology ensures that frequency response remains uniform regardless of the speaker load, allowing for consistent performance across a wide variety of 2 to 16-ohm loudspeaker designs.
Sonically, the amplifier delivers the intimate, tactile presence synonymous with direct-heated triodes, yet possesses the grip and dynamic headroom typically reserved for far more powerful designs. It is an instrument of remarkable balance, presenting complex musical textures with poise, clarity, and an expansive soundstage that serves the performance above all else.
Key Features
01
Direct-coupled signal path
Features zero coupling capacitors, chokes, or transformers in the signal section, ensuring absolute transparency.
02
Linear Field output transformer
Ensures the frequency response remains completely stable and independent of the connected speaker impedance.
03
GM70 direct-heated triode
Utilises high-performance military-grade GM70 output tubes for a pure, zero-feedback class A experience.
04
Balanced connectivity
One of the few single-ended integrated amplifiers to offer both true balanced inputs and outputs.
05
Adaptive bias control
Automatically manages output tube dissipation to maintain constant current performance throughout the tube lifespan.
Chapter 01
Design & Philosophy
The engineering philosophy behind the Single Evo focuses on the removal of mechanical and electrical barriers. By utilizing nano-crystalline core input transformers, the design preserves the integrity of balanced signal sources while maintaining a strictly single-ended amplification topology. This is a deliberate choice for those who value signal purity over the convenience of traditional circuit designs.
Chapter 02
Build & Materials
Each unit is housed in a substantial chassis crafted from 20mm thick solid aluminium, providing a rigid, non-resonant foundation. The internal power supply is equally overbuilt, featuring five separate sections with over 300 Joules of energy storage, ensuring that the 50W output stage is never starved of current during demanding dynamic peaks.
Chapter 03
Sonic Signature
The Single Evo does not impose a signature; it reveals the recording as it exists. Listeners will note a lack of the traditional 'tube bloom' in favour of a more accurate, percussive, and physically present soundstage. It is a revealing, honest amplifier that rewards high-sensitivity speaker systems with a rare combination of holographic imaging and rhythmic authority.
Specifications
TypeSingle-ended class A integrated tube amplifier
Frequency response8 Hz to 60 kHz
Power / output50 W @ 8 ohms
Inputs / outputsBalanced and RCA inputs, subwoofer pre-out
Dimensions (H × W × D)330 mm × 483 mm × 400 mm
Weight39 kg
Finish optionsBlack or silver aluminium