Description
PrimaLuna EVO 400 Valve Preamplifier
The PrimaLuna EVO 400 Valve Preamplifier is a premium high-end stereo preamplifier designed to deliver outstanding musical transparency, natural tonal richness and exceptional performance in sophisticated hi-fi systems.
As the flagship valve preamplifier in PrimaLuna’s EVO Series, the EVO 400 combines a dual-mono circuit architecture, premium valve rectification, carefully selected components and extensive analogue connectivity.
Featuring six 12AU7 signal valves and two 5AR4 rectifier valves, the EVO 400 provides a refined analogue foundation for demanding stereo systems.
Designed to partner a high-quality separate power amplifier, it offers both balanced XLR and conventional RCA connections, making it particularly versatile for premium hi-fi installations.
Premium All-Valve Preamplification
The EVO 400 uses six 12AU7 valves in its audio circuitry to provide natural, detailed and expressive music reproduction.
Its carefully engineered valve architecture is designed to preserve musical dynamics, tonal accuracy and stereo imaging.
Unlike an integrated amplifier, the EVO 400 does not contain a loudspeaker power amplification stage.
It must be connected to a compatible stereo or mono power amplifier.
Dual-Mono Circuit Architecture
The EVO 400 features a sophisticated dual-mono design intended to maintain separation between the left and right audio channels.
This arrangement supports precise stereo imaging, excellent channel separation and a spacious musical presentation.
Valve Rectification
Two 5AR4 rectifier valves form part of the preamplifier’s power supply design.
Valve rectification is a distinctive feature of PrimaLuna’s premium preamplifier architecture and contributes to its carefully engineered power supply.
Premium Power Supply
The EVO 400 incorporates custom-designed transformers and high-quality power supply components.
PrimaLuna’s AC Offset Killer circuitry is designed to reduce unwanted transformer noise caused by DC offset on the mains supply.
This helps provide quieter mechanical operation in suitable electrical environments.
Traditional Point-to-Point Wiring
The EVO 400 features carefully assembled point-to-point wiring and premium internal components.
Its construction includes:
- Custom-designed transformers
- Premium internal signal wiring
- High-quality resistors and capacitors
- ALPS volume control
- Ceramic valve sockets
- Gold-plated RCA connections
- Balanced XLR connectivity
- Heavy-gauge ventilated steel chassis
This approach reflects PrimaLuna’s emphasis on build quality and long-term serviceability.
Balanced XLR Connectivity
The EVO 400 provides two pairs of balanced stereo XLR inputs and one pair of balanced stereo XLR outputs.
Balanced connections are particularly useful when partnering compatible high-end DACs, network streamers and power amplifiers.
They can help reduce susceptibility to interference in appropriately configured systems.
RCA Analogue Connectivity
Three stereo RCA inputs provide connectivity for conventional analogue sources, including:
- CD players
- Network music streamers
- External digital-to-analogue converters
- Phono preamplifiers
- Other compatible line-level audio components
Home Theatre Bypass
A dedicated home theatre bypass input allows the EVO 400 to be incorporated into a combined high-end stereo and home cinema system.
With suitable system configuration, a compatible AV processor can control the front-channel signal during home cinema playback.
Flexible Analogue Outputs
The EVO 400 provides variable RCA and XLR stereo outputs for connection to compatible power amplifiers.
A separate fixed-level RCA tape output is also provided.
This combination makes the EVO 400 suitable for a wide range of premium audio systems.
Optional Moving-Magnet Phono Stage
The EVO 400 is compatible with PrimaLuna’s optional PhonoLogue EVO moving-magnet phono stage.
Alternatively, an external phono preamplifier can be connected through a standard analogue input.
The optional phono stage is not included as standard.
Remote Control
A substantial remote control provides convenient operation from the listening position.
Premium Construction
The EVO 400 features a heavy-gauge ventilated steel chassis, substantial transformers and carefully selected internal components.
Its 24kg net weight reflects the substantial construction expected from a high-end valve preamplifier.
Key Features
- Flagship PrimaLuna EVO Series valve preamplifier
- Premium all-valve analogue circuitry
- Dual-mono design
- Six 12AU7 signal valves
- Two 5AR4 rectifier valves
- Custom-designed power supply
- PrimaLuna AC Offset Killer circuitry
- Traditional point-to-point wiring
- Premium internal components
- Three stereo RCA inputs
- Two stereo XLR inputs
- Dedicated home theatre bypass input
- Stereo RCA preamplifier output
- Stereo balanced XLR preamplifier output
- Fixed-level RCA tape output
- Optional PhonoLogue EVO MM phono stage
- Remote control included
- Heavy-gauge ventilated steel chassis
- Designed for premium separate power amplifiers
Complete Technical Specifications
| Specification | Details |
|---|---|
| Manufacturer | PrimaLuna |
| Model | EVO 400 Preamplifier |
| Manufacturer model reference | EVO 400-3 |
| Product type | Stereo valve preamplifier |
| Circuit architecture | Dual-mono |
| Signal valves | 6 × 12AU7 |
| Rectifier valves | 2 × 5AR4 |
| Total valve complement | 8 |
| Rated output | 2V per channel |
| Frequency response | 18Hz–38kHz ±1dB |
| Extended frequency response | 12Hz–75kHz ±3dB |
| Total harmonic distortion | Less than 0.5% at 2V |
| Signal-to-noise ratio | 93dB |
| A-weighted signal-to-noise ratio | 98dB |
| Input impedance | 220kΩ |
| Output impedance | 256Ω |
| Input sensitivity | 650mV for rated output at maximum volume |
| Gain | 9.7dB |
| Stereo RCA inputs | 3 pairs |
| Stereo XLR inputs | 2 pairs |
| Home theatre input | 1 stereo pair |
| Stereo RCA preamplifier output | 1 pair |
| Stereo XLR preamplifier output | 1 pair |
| RCA tape output | 1 pair |
| Optional phono stage | PrimaLuna PhonoLogue EVO MM |
| Remote control | Included |
| Power consumption | 61W |
| Loudspeaker power output | None — separate power amplifier required |
Dimensions & Weight
| Measurement | Specification |
|---|---|
| Width | 385 mm |
| Height | 205 mm |
| Depth | 405 mm |
| Overall dimensions (W × H × D) | 385 × 205 × 405 mm |
| Net weight | 24 kg |
| Shipping weight | 29 kg |
| Shipping dimensions (W × H × D) | 468 × 315 × 577 mm |
Installation Considerations
The PrimaLuna EVO 400 is a substantial valve preamplifier weighing 24kg.
It should be installed on a stable, suitably rated equipment shelf with adequate ventilation.
As the valves generate heat during operation, sufficient clearance should be provided above and around the unit.
For optimum performance, the preamplifier should be partnered with a compatible high-quality power amplifier and carefully selected loudspeakers.
Balanced XLR connections may be particularly beneficial where compatible equipment is used.
Recommended Applications
The EVO 400 is particularly suitable for:
- High-end two-channel stereo systems
- Dedicated audiophile listening rooms
- Premium valve or solid-state power amplifiers
- High-resolution network music streaming
- High-performance CD and DAC systems
- Audiophile vinyl playback systems with a suitable phono stage
- Combined stereo and home cinema installations
- Luxury residential hi-fi systems
Expert PrimaLuna Advice at Riverside HiFi
At Riverside HiFi, we specialise in premium hi-fi, valve amplification, high-performance loudspeakers and complete music system design.
Our services include:
- Valve preamplifier and power amplifier matching
- High-end stereo system design
- Loudspeaker selection and demonstrations
- Turntable and phono stage integration
- Network streamer and DAC selection
- Premium interconnect and loudspeaker cable advice
- Home cinema and smart home integration
- Professional installation and system optimisation
Whether you’re building a new high-end separates system or upgrading an existing installation, Riverside HiFi can help you select the ideal components to complement the PrimaLuna EVO 400.
Riverside HiFi – Hi-Fi | Home Cinema | Smart Home | Professional Installation
Important: This product is a stereo preamplifier only. A separate power amplifier is required to drive passive loudspeakers.
