Description
PrimaLuna EVO 400 Integrated Valve Amplifier
The PrimaLuna EVO 400 Integrated Valve Amplifier is a flagship all-valve stereo amplifier combining traditional valve musicality with sophisticated engineering, premium components and exceptional build quality.
Designed for discerning hi-fi enthusiasts, the EVO 400 delivers a rich, detailed and engaging listening experience, with outstanding tonal character, natural vocals and impressive musical dynamics.
Featuring eight EL34 output valves, six 12AU7 valves, PrimaLuna’s proprietary Adaptive AutoBias system and selectable ultralinear or triode operation, the EVO 400 provides a versatile foundation for a high-performance stereo music system.
Premium All-Valve Amplification
The EVO 400 uses a carefully engineered valve amplification circuit to deliver natural, expressive music reproduction.
With the standard EL34 output valves, it produces:
- 70 watts per channel in ultralinear mode
- 38 watts per channel in triode mode
Ultralinear operation provides greater power and dynamic authority, while triode operation offers an alternative presentation that many valve enthusiasts appreciate for its tonal character and refinement.
Both modes can be selected using the supplied remote control.
PrimaLuna Adaptive AutoBias Technology
PrimaLuna’s proprietary Adaptive AutoBias system automatically monitors and adjusts output valve bias during operation.
This sophisticated technology helps maintain optimum valve operating conditions, reducing the need for manual bias adjustments.
It also allows compatible alternative output valve types to be used without conventional manual rebiasing.
Compatible Output Valve Options
The EVO 400 is supplied with eight EL34 output valves but also supports compatible KT88, KT120 and KT150 valves.
Different valve types provide alternative power outputs and sonic characteristics.
| Output valves | Ultralinear power | Triode power |
|---|---|---|
| EL34 – standard | 2 × 70W | 2 × 38W |
| KT88 | 2 × 72W | 2 × 40W |
| KT120 | 2 × 85W | 2 × 45W |
| KT150 | 2 × 88W | 2 × 50W |
Alternative valves are available separately. Valve substitution should follow PrimaLuna’s compatibility and operating instructions.
Premium Output Transformers
Custom-designed output transformers are central to the EVO 400’s performance.
Engineered for wide bandwidth and low distortion, these substantial transformers help deliver controlled bass, detailed midrange reproduction and extended high-frequency performance.
Point-to-Point Wiring
The EVO 400 uses traditional point-to-point wiring rather than relying entirely on printed circuit boards for its audio signal path.
This construction approach allows careful component placement and supports long-term serviceability.
Premium components include:
- Custom-designed output transformers
- High-quality toroidal and EI power transformers
- ALPS volume control
- Premium capacitors and resistors
- Ceramic valve sockets
- Gold-plated RCA connections
- Heavy-duty loudspeaker terminals
Dedicated Headphone Amplification
The EVO 400 incorporates a dedicated valve-powered headphone listening facility.
A front-panel 6.35mm headphone connection allows private listening with compatible headphones.
Home Theatre Bypass
A dedicated home theatre input allows the EVO 400 to be incorporated into a combined stereo and home cinema system.
This enables compatible AV processors or receivers to control the front-channel signal when using the EVO 400 for amplification.
Flexible Analogue Connectivity
Five stereo RCA inputs accommodate a range of analogue music sources, including:
- Network music streamers
- External DACs
- CD players
- Phono preamplifiers
- Other compatible analogue sources
A dedicated home theatre bypass input, tape output and subwoofer outputs provide additional system flexibility.
An optional MM phono stage can be fitted where compatible.
Premium Construction
The EVO 400 features a substantial, fully ventilated steel chassis with a carefully finished exterior.
Its premium construction, high-quality transformers and robust internal components contribute to its substantial 31kg weight.
The amplifier is available with black or silver front-panel finishes.
Key Features
- Flagship PrimaLuna EVO Series integrated valve amplifier
- Eight EL34 output valves
- Six 12AU7 small-signal valves
- 70W per channel in ultralinear mode with EL34 valves
- 38W per channel in triode mode with EL34 valves
- Selectable ultralinear and triode operation
- Proprietary Adaptive AutoBias technology
- Compatible with selected alternative output valves
- Premium custom-designed output transformers
- Point-to-point wiring
- High-quality analogue volume control
- Five stereo RCA inputs
- Dedicated home theatre bypass input
- Stereo/mono subwoofer outputs
- Tape output
- Dedicated headphone connection
- 4Ω and 8Ω loudspeaker connections
- Remote control
- Premium steel chassis
- Black or silver finish options
Complete Technical Specifications
| Specification | Details |
|---|---|
| Manufacturer | PrimaLuna |
| Model | EVO 400 Integrated |
| Product type | Integrated stereo valve amplifier |
| Amplifier design | All-valve, push-pull |
| Standard output valves | 8 × EL34 |
| Small-signal valves | 6 × 12AU7 |
| Total supplied valves | 14 |
| Alternative compatible output valves | KT88, KT120, KT150 |
| Output power, EL34 ultralinear | 2 × 70W |
| Output power, EL34 triode | 2 × 38W |
| Output power, KT88 ultralinear | 2 × 72W |
| Output power, KT88 triode | 2 × 40W |
| Output power, KT120 ultralinear | 2 × 85W |
| Output power, KT120 triode | 2 × 45W |
| Output power, KT150 ultralinear | 2 × 88W |
| Output power, KT150 triode | 2 × 50W |
| Bias system | Adaptive AutoBias |
| Frequency response | 9Hz–50kHz ±1dB |
| Extended frequency response | 8Hz–68kHz ±3dB |
| Total harmonic distortion | Below 0.1% at 1W; below 2% at rated power |
| Signal-to-noise ratio | 90dB; 98dB A-weighted |
| Input impedance | 100kΩ |
| Input sensitivity with EL34 valves | 320mV |
| Maximum gain, EL34 ultralinear | 37dB |
| Maximum gain, EL34 triode | 36.5dB |
| Stereo analogue inputs | 5 × RCA pairs |
| Home theatre input | 1 × stereo RCA pair |
| Loudspeaker outputs | 4Ω and 8Ω transformer taps |
| Additional outputs | Tape, stereo/mono subwoofer, headphone |
| Headphone connection | 6.35mm jack |
| Phono stage | Optional MM phono module |
| Remote control | Included |
| Power consumption with EL34 valves | 470W |
| Power consumption with KT88 valves | 480W |
| Power consumption with KT120 valves | 540W |
| Power consumption with KT150 valves | 550W |
| Construction | Ventilated steel chassis |
| Available finishes | Black or silver front panel |
Dimensions & Weight
| Measurement | Specification |
|---|---|
| Width | 385 mm |
| Height | 205 mm |
| Depth | 405 mm |
| Dimensions (W × H × D) | 385 × 205 × 405 mm |
| Net weight | 31 kg |
| Shipping weight | 36 kg |
| Shipping dimensions | 577 × 468 × 315 mm |
Installation Considerations
The PrimaLuna EVO 400 is a substantial valve amplifier weighing 31kg.
It requires a strong, stable equipment shelf with adequate ventilation.
Valve amplifiers generate significant heat during operation, so sufficient clearance must be provided around and above the unit.
The amplifier should not be operated without suitable loudspeakers connected, and loudspeaker impedance should be matched to the appropriate output terminals.
Recommended Applications
The PrimaLuna EVO 400 is particularly suitable for:
- Premium two-channel stereo systems
- Dedicated hi-fi listening rooms
- High-performance floorstanding loudspeakers
- Audiophile vinyl playback systems
- Premium CD and network streaming systems
- Combined stereo and home cinema installations
- Music enthusiasts seeking traditional valve amplification
Expert PrimaLuna Advice at Riverside HiFi
At Riverside HiFi, we specialise in premium hi-fi, valve amplification, loudspeaker matching and complete high-performance music systems.
Our services include:
- Valve amplifier and loudspeaker matching
- Premium stereo system design
- Turntable and phono stage integration
- Network music streamer and DAC selection
- High-performance loudspeaker demonstrations
- Professional installation and system optimisation
- Home cinema and smart home integration
Whether you’re upgrading an existing stereo system or building a dedicated listening room, Riverside HiFi can help you select the ideal equipment to complement the PrimaLuna EVO 400.
Riverside HiFi – Hi-Fi | Home Cinema | Smart Home | Professional Installation
