The Marantz MODEL 40n is a premium integrated stereo amplifier designed for systems that combine traditional analog sources with modern network streaming and TV connectivity. It combines a 70-watt-per-channel Class A/B amplifier, Marantz HDAM-SA3 circuitry, a built-in MM phono stage, HEOS streaming, HDMI eARC, and a full range of digital and analog inputs.
 
With 70 watts per channel into 8 ohms and 100 watts per channel into 4 ohms, the MODEL 40n provides enough power for a broad range of bookshelf and floorstanding loudspeakers. Its double-shielded toroidal transformer and high-current output stage are designed to provide stable power delivery while maintaining the smooth, detailed presentation associated with Marantz amplification.
 
Class A/B Amplification with HDAM-SA3
The MODEL 40n uses a discrete Class A/B power amplifier with Marantz's HDAM-SA3 circuitry. The amplifier is rated at 70W + 70W into 8 ohms and 100W + 100W into 4 ohms, with a damping factor of 100.
A double-shielded toroidal transformer supplies the amplifier section, while Source Direct mode provides a shortened signal path by bypassing the tone-control circuitry.
 
HEOS Built-In Streaming
HEOS provides direct access to network music without requiring a separate streamer. The MODEL 40n can stream from services including TIDAL, Spotify, Amazon Music, Pandora and TuneIn, while AirPlay 2 and Bluetooth provide additional wireless playback options.
 
The MODEL 40n is also Roon Ready and supports high-resolution network playback. HEOS allows the amplifier to be integrated into a multi-room system with other compatible HEOS products.
 
HDMI eARC for TV Audio
An HDMI eARC connection makes the MODEL 40n particularly useful in a two-channel system that also serves as a television system. A single HDMI cable can carry audio from a compatible TV directly to the amplifier, with TV volume and power functions available through HDMI-CEC.
 
Optical and coaxial digital inputs provide additional connections for disc players, streamers, televisions and other digital sources.
 
MM Phono Stage
The built-in Marantz Musical Phono EQ supports moving-magnet cartridges and provides a dedicated analog input for a turntable. With 87dB signal-to-noise performance and ±0.5dB RIAA deviation from 20Hz to 20kHz, the phono stage is designed to integrate cleanly into a high-performance two-channel system.
Subwoofer Integration
The MODEL 40n includes a dedicated subwoofer output with selectable low-pass filtering at 40Hz, 60Hz, 80Hz, 100Hz or 120Hz. This allows the amplifier to be integrated with a powered subwoofer while maintaining a straightforward two-channel setup.
 
Analog and Digital Connectivity
Along with its MM phono input, the MODEL 40n provides CD, line-level and recorder inputs, a recorder output, optical and coaxial digital inputs, rear-panel USB-A for compatible USB storage, and a Power Amp Direct input.
 
Bass, treble and balance controls are available for system adjustment, while Source Direct bypasses the tone-control circuitry when a more direct signal path is preferred.
 
The front panel combines an aluminum center panel and aluminum controls with Marantz's signature porthole display and dimmable edge lighting. The MODEL 40n is available in Black and Silver-Gold finishes.
 
Key Features
• 70W + 70W into 8 ohms
• 100W + 100W into 4 ohms
• Class A/B amplification
• Marantz HDAM-SA3 circuitry
• Double-shielded toroidal transformer
• HEOS Built-in network streaming
• Roon Ready
• AirPlay 2
• Bluetooth
• HDMI eARC
• MM phono input
• Marantz Musical Phono EQ
• Optical and coaxial digital inputs
• Rear USB-A input
• Power Amp Direct input
• Dedicated subwoofer output
• Selectable subwoofer low-pass filter
• Bass, treble and balance controls
• Source Direct mode
• Damping factor of 100
• Porthole display
• Dimmable edge lighting
• Aluminum front panel and controls
• Control4 and Josh.ai compatible