Atoll Electronique CD400 Evolution black

Fourteen years after the introduction of the first CD400, Atoll is renewing its flagship with this Evolution version. The Normandy-based manufacturer has thoroughly redesigned the mechanism, power supplies, and conversion stages to create a player that lives up to its ambitions. With its dual mono architecture, ten regulated power supplies, and in-house-developed top-loading mechanism, this French player draws on nearly three decades of expertise in designing high-fidelity electronics.

A proprietary top-loading mechanism

The heart of the CD400 Evolution is a reading mechanism designed and manufactured by Atoll. The top-loading system, combined with a massive aluminum platter mounted on suspension, effectively isolates the disc from unwanted vibrations. This construction, decoupled from the main chassis, improves the accuracy of laser reading and reduces jitter. A magnetic clamp holds the CD in place during playback.

The mechanism accepts commercial CDs as well as CD-R and CD-RW burned discs, including those containing MP3, WMA, or AAC files. CD Text display is supported when the disc contains such metadata.

Dual mono architecture and high-end conversion

Each audio channel has its own Burr-Brown PCM1792A digital-to-analog converter, a chip renowned for its linearity and dynamics. This fully dual mono configuration continues with independent symmetrical stages for each channel, minimizing crosstalk.

The output stages are based on bipolar transistors biased in class A, operating without global feedback. This technical choice promotes linear behavior and low harmonic distortion (0.002% at 1 kHz). Current sources use transistors and LEDs to ensure optimal stability. High-quality MKP coupling capacitors complete the audio circuit.

A power supply serving musicality

The power supply is often the weak link in digital sources. Atoll has opted for an architecture with four separate transformers: a 30 VA linear transformer for the general power supply, two 10 VA toroidal transformers dedicated to the audio stages (one per channel), and a 1.6 VA transformer for control logic. This separation prevents interference between digital and analog circuits.

Ten independent regulators power the different sections of the player, for a total filtering capacity of 48,000 µF. This generous energy reserve ensures dynamics of 132 dB and an equivalent signal-to-noise ratio.

An integrated external DAC

Beyond CD playback, the CD400 Evolution can serve as a digital-to-analog converter for other sources. Three digital inputs are available: an asynchronous USB-B input compatible with PCM streams up to 32-bit/192 kHz (XMOS chip with firmware developed specifically for Atoll), a coaxial S/PDIF input, and an optical S/PDIF input, the latter two accepting signals up to 24-bit/192 kHz. A network player, computer, or television can thus benefit from the CD400’s conversion section.

On the output side, the player offers comprehensive analog connectivity with unbalanced RCA and balanced XLR outputs. Three digital outputs (AES/EBU, coaxial, and optical) allow the CD400 to be used as a CD transport feeding an external converter.

Build and finish

The chassis combines a 2 mm steel structure with solid aluminum side panels. The 10 mm-thick front panel, brushed, micro-bead blasted, and anodized, features high-precision engraving. Two finishes are available: natural aluminum or black.

The high-contrast OLED display shows playback information and can switch off automatically after five seconds of inactivity. Six front-panel buttons provide access to the main functions. The supplied remote control can operate all Atoll devices (amplifiers, preamplifiers, tuners, DACs) and offers advanced functions such as programming, random playback, or repeat.

Integration into an audio system

The CD400 Evolution naturally pairs with other components in Atoll’s 400 Evolution range (IN400 Evolution integrated amplifier, PR400 preamplifier and AM400 power amplifier, DR400 Evolution CD transport). The balanced XLR outputs fully exploit the potential of amplifiers equipped with balanced inputs, while the RCA outputs ensure compatibility with any hi-fi system.

The USB input requires the installation of a specific driver under Windows, available for download from the Atoll website. macOS and Linux systems generally recognize the player without any additional drivers.

Technical Specifications

Construction and Chassis

• 10 mm solid aluminum front panel, brushed, bead-blasted, and anodized
• Solid aluminum side panels
• 2 mm steel chassis with anti-vibration system
• Top-loading mechanism developed in-house with suspended mounting and solid aluminum platter
• High-contrast OLED display with automatic standby function
• ATOLL remote control included

Power Supply

• 2 toroidal transformers of 10 VA for the audio stages
• 1 linear transformer of 30 VA for the main power supply
• 1 linear transformer of 1.6 VA for control logic
• 10 regulated and independent power supplies
• Total capacitance: 48,000 µF

Audio Conversion and Processing

• Dual PCM1792A DACs, one per channel
• 100% balanced audio processing
• Class A bipolar transistor audio stages, without feedback
• Current sources by transistors and LEDs for optimal stability

Audio Performance

• Signal-to-noise ratio: 132 dB
• Dynamic range: 132 dB
• Total harmonic distortion at 1 kHz: 0.002%
• Slew rate: 1.3 µs
• Output impedance: 5.6 Ω
• Output level: 2.1 Vrms

Connectivity

• Digital inputs
  • 1 coaxial S/PDIF input 24-bit / 192 kHz
  • 1 optical S/PDIF input 24-bit / 192 kHz
  • 1 asynchronous USB-B XMOS input: PCM 16 to 32-bit up to 192 kHz
• Audio outputs
  • 1 balanced stereo XLR output
  • 1 unbalanced stereo RCA output
  • 1 AES/EBU output
  • 1 optical digital output
  • 1 coaxial digital output

General Information

• Dimensions: 440 × 340 × 100 mm
• Weight: 12 kg
• Standby power consumption: < 0.5 W
• Operating power consumption: 18 to 24 W