Marantz STEREO 70s Network Stereo Receiver

75 Wpc class-AB amplification with HEOS streaming, six HDMI inputs, 8K video support, and MM phonostage

The Marantz STEREO 70s combines traditional two-channel hi-fi performance with the extensive connectivity and convenience features of a modern AV receiver. Delivering 75 W per channel into 8 Ω, the STEREO 70s incorporates discrete class-AB amplification, Marantz HDAM circuitry, high-resolution network streaming, six HDMI inputs, and a built-in MM phonostage in a slim, elegant chassis.

Designed for listeners who want a high-quality stereo music system that can also handle television, movies, and gaming, the STEREO 70s brings many of the capabilities found in Marantz's CINEMA Series receivers to a dedicated two-channel design. With HEOS Built-in, Apple AirPlay 2, Bluetooth, Spotify Connect, and HDMI ARC, it can accommodate an extensive range of music and entertainment sources without the complexity of a multichannel home theater system.

Discrete Class-AB Amplification

At the heart of the STEREO 70s is a fully discrete, two-channel class-AB power amplifier rated at 75 W per channel into 8 Ω, measured from 20 Hz to 20 kHz with both channels driven and total harmonic distortion of 0.08%. Power increases to 100 W per channel into 6 Ω at 1 kHz with both channels driven and 0.7% THD.

Unlike multichannel AV receivers that must distribute their available power across numerous speakers, the STEREO 70s concentrates its amplification on two channels. This approach makes it particularly well suited to conventional bookshelf and floorstanding loudspeakers while retaining the flexibility of modern home entertainment connectivity.

The amplifier incorporates Marantz's proprietary Hyper Dynamic Amplifier Modules (HDAM), which use discrete components rather than conventional integrated-circuit operational amplifiers in critical signal stages. These circuits are designed to provide high slew rates and wide bandwidth, helping the amplifier respond accurately to the changing demands of music.

Marantz's Sound Master tuning process further refines the amplifier's performance through careful component selection and extensive listening evaluations. The result is a receiver designed to deliver the company's characteristic combination of musical detail, tonal richness, and spacious imaging.

High-Resolution Music Streaming With HEOS

With HEOS Built-in, the STEREO 70s provides convenient access to music streaming services, internet radio, and locally stored digital music. The HEOS app allows listeners to browse music, select sources, adjust volume, and control playback from a smartphone or tablet. Supported services include Amazon Music, TIDAL, Spotify, Pandora, Deezer, and others, with availability varying by region.

For listeners with their own digital music libraries, the STEREO 70s supports high-resolution PCM files up to 24-bit/192 kHz and DSD files at 2.8 MHz and 5.6 MHz. Music can be played from compatible network-attached storage devices, computers on the local network, or USB storage connected directly to the receiver.

Gapless playback is supported for FLAC, WAV, ALAC, and DSD files, allowing live albums, classical recordings, and other continuous performances to play without interruptions between tracks.

Apple AirPlay 2 makes it easy to stream directly from an iPhone, iPad, or Mac, while Bluetooth provides a convenient wireless connection for compatible devices. Spotify Connect offers direct control of Spotify playback from the Spotify app. The STEREO 70s is also Roon Tested, providing additional flexibility for listeners using Roon to organize and play their digital music collections.

Multiroom Audio Made Simple

The STEREO 70s can also be part of a larger HEOS multiroom audio system. Connect additional HEOS-enabled Marantz or Denon components throughout the home, and use the HEOS app to play different music in different rooms or synchronize playback across multiple listening areas.

A dedicated stereo zone preamplifier output allows the receiver to send audio to an external amplifier serving another room. This provides a useful option for expanding a listening system without requiring an entirely separate source component.

Bluetooth retransmission also allows audio to be sent from the receiver to compatible Bluetooth headphones, with independent volume control for convenient private listening.

Home Cinema From Just Two Channels

One of the STEREO 70s' distinguishing features is its ability to handle modern television and video sources while remaining a dedicated stereo receiver. Six HDMI inputs accommodate televisions, streaming media players, game consoles, Blu-ray players, and other compatible components, with three inputs supporting 8K video signals.

The receiver supports 8K/60 Hz and 4K/120 Hz video pass-through on compatible HDMI connections, along with HDR10+, Dolby Vision, Hybrid Log-Gamma (HLG), and Dynamic HDR. HDCP 2.3 compatibility helps ensure reliable operation with protected digital video sources.

An HDMI output with Audio Return Channel (ARC) allows audio from a compatible television to be played through conventional stereo loudspeakers. HDMI-CEC support also allows compatible television remotes to control power and volume, simplifying everyday operation.

With the STEREO 70s, listeners can enjoy the improved dialogue intelligibility, dynamics, and soundstage of a dedicated stereo speaker system without requiring a full surround sound installation.

Gaming Features and 8K Video Processing

The STEREO 70s incorporates several HDMI technologies intended to improve the gaming experience. Variable Refresh Rate (VRR) helps reduce screen tearing, while Auto Low Latency Mode (ALLM) allows compatible equipment to switch automatically to a low-latency setting.

Quick Frame Transport (QFT) further helps reduce latency between a gaming source and the display. Together, these features make the receiver suitable for modern gaming consoles and other video sources that benefit from high refresh rates and responsive performance.

Video upscaling from 1080p or 4K to 8K is also supported, allowing lower-resolution video sources to be output at 8K resolution when used with compatible displays.

Two Subwoofer Outputs and Flexible Speaker Configuration

Although the STEREO 70s is designed around two primary audio channels, it provides two subwoofer outputs for systems requiring greater low-frequency extension. This 2.2-channel configuration makes it possible to combine a pair of compact bookshelf loudspeakers with one or two powered subwoofers, creating a full-range stereo system without the need for large floorstanding speakers.

Speaker A/B switching provides connections for two pairs of loudspeakers, allowing listeners to select between speaker systems or operate compatible configurations according to their requirements.

The receiver also includes 2.2-channel preamplifier outputs, making it possible to use an external power amplifier while retaining the STEREO 70s' source selection, streaming, and control capabilities.

Built-In MM Phonostage

For vinyl enthusiasts, the STEREO 70s includes a dedicated moving-magnet phonostage. This allows a turntable fitted with a compatible MM cartridge to connect directly to the receiver without requiring a separate external phono preamplifier.

The receiver also provides three stereo RCA analog inputs for components such as CD players, tape decks, and external DACs. Gold-plated RCA terminals provide reliable connections and help resist corrosion over time.

By combining analog connectivity with modern streaming and video capabilities, the STEREO 70s can accommodate both traditional hi-fi sources and the latest digital entertainment equipment.

Digital Audio and Listening Modes

In addition to its HDMI connections, the STEREO 70s provides optical and coaxial digital inputs for compatible CD transports, televisions, and other digital audio sources. These inputs allow the receiver's internal digital-to-analog conversion circuitry to be used with a range of external components.

Pure Direct mode minimizes unnecessary processing and circuitry during music playback, providing a more direct signal path for listeners who prefer a traditional two-channel listening experience.

Marantz's M-DAX2 compressed audio enhancement technology is also included. This processing is designed to improve the perceived quality of compressed digital audio files by addressing some of the high-frequency information lost during compression.

For conventional radio listening, the STEREO 70s includes an AM/FM tuner, providing an additional source that does not require an internet connection.

Slimline Design and Easy System Integration

The STEREO 70s incorporates its extensive connectivity and amplification into a chassis measuring just 4.3" high, allowing it to fit into spaces where a full-size AV receiver may be impractical. Its understated front panel features Marantz's distinctive circular OLED display and a symmetrical arrangement of controls.

An on-screen setup assistant simplifies initial installation by guiding users through speaker connections, source configuration, and network setup. The Marantz AVR Remote app provides control of receiver functions from a compatible smartphone or tablet, while the HEOS app handles music streaming and multiroom playback.

Wired Ethernet and Wi-Fi provide flexible network connectivity. The receiver also supports popular voice-control platforms and custom installation systems, including IP and IR control integration.

Additional conveniences include HDMI pass-through in standby mode, an automatic power-off function, sleep timer, and Eco mode to help manage power consumption.

Features

• Two-channel stereo network receiver with 2.2-channel audio capability
• 75 W per channel into 8 Ω (20 Hz–20 kHz, 0.08% THD, two channels driven)
• 100 W per channel into 6 Ω (1 kHz, 0.7% THD, two channels driven)
• Fully discrete class-AB power amplification
• Proprietary Marantz Hyper Dynamic Amplifier Modules (HDAM)
• Marantz Sound Master tuning with carefully selected audio components
• HEOS Built-in for high-resolution music streaming and multiroom audio
• Apple AirPlay 2, Bluetooth, and Spotify Connect
• Roon Tested compatibility
• High-resolution PCM playback up to 24-bit/192 kHz and DSD up to 5.6 MHz
• Gapless playback for FLAC, WAV, ALAC, and DSD files
• Six HDMI inputs and one HDMI output with ARC
• Three HDMI inputs supporting 8K/60 Hz and 4K/120 Hz video
• HDR10+, Dolby Vision, HLG, and Dynamic HDR compatibility
• 8K video upscaling from 1080p and 4K sources
• HDCP 2.3 compatibility
• Variable Refresh Rate (VRR), Auto Low Latency Mode (ALLM), and Quick Frame Transport (QFT)
• HDMI-CEC and HDMI pass-through in standby mode
• Two subwoofer outputs for 2.2-channel systems
• 2.2-channel preamplifier outputs for external amplification
• Speaker A/B switching with connections for two pairs of loudspeakers
• Dedicated moving-magnet phonostage for turntable connection
• Three stereo RCA analog inputs
• Optical and coaxial digital audio inputs
• USB-A input for music playback from compatible storage devices
• AM/FM tuner
• Pure Direct listening mode
• M-DAX2 compressed audio enhancement
• Bluetooth retransmission for compatible wireless headphones
• Dedicated stereo zone preamplifier output
• Dual-band Wi-Fi and wired Ethernet connectivity
• Voice assistant compatibility with supported platforms
• Marantz AVR Remote app and HEOS app control
• On-screen setup assistant
• Custom installation compatibility with IR and IP control
• Front-panel circular OLED display
• Slimline chassis measuring just 4.3" high
• Eco mode, sleep timer, and automatic power-off
• Five-year manufacturer's limited warranty

What's Included

• Marantz STEREO 70s receiver
• Remote control (RC-052SR)
• Batteries for remote control
• AM/FM antennas
• Two external detachable wireless antennas
• Speaker wire labels
• Quick start guide
• AC power cord

Specifications

Type: Network stereo receiver with HDMI switching

Amplifier Design: Discrete class-AB with Marantz HDAM circuitry

Channels: 2.2

Powered Channels: 2

Power Output (8 Ω): 75 W per channel (20 Hz–20 kHz, 0.08% THD, two channels driven)

Power Output (6 Ω): 100 W per channel (1 kHz, 0.7% THD, two channels driven)

Maximum Power Output (6 Ω): 150 W (1 kHz, 10% THD, one channel driven)

Amplifier Technology: Discrete power amplifier with Hyper Dynamic Amplifier Modules (HDAM)

Speaker Outputs: Speaker A/B, four pairs of terminals

HDMI Inputs: 6 (3 supporting 8K)

HDMI Outputs: 1 (ARC)

Maximum HDMI Video Resolution: 8K/60 Hz, 4K/120 Hz

HDMI Upscaling: 1080p/4K to 8K

HDMI Copy Protection: HDCP 2.3

HDR Compatibility: HDR10, HDR10+, Dolby Vision, HLG, Dynamic HDR

Gaming Features: Variable Refresh Rate (VRR), Auto Low Latency Mode (ALLM), Quick Frame Transport (QFT)

HDMI Features: ARC, HDMI-CEC, standby pass-through

Analog Inputs: 3 stereo RCA

Phono Input: Moving magnet (MM)

Digital Inputs: 1 optical (TOSLINK), 1 coaxial

Analog Outputs: Fixed-level stereo RCA

Preamplifier Outputs: 2.2 channels

Subwoofer Outputs: 2

Zone Outputs: Stereo analog RCA

USB Input: USB-A for compatible storage devices

Supported Audio Formats: FLAC, WAV, ALAC, MP3, WMA, AAC, DSD

PCM Resolution: Up to 24-bit/192 kHz

DSD Support: 2.8 MHz, 5.6 MHz

Gapless Playback: FLAC, WAV, ALAC, DSD

Compressed Audio Enhancement: Marantz M-DAX2

Streaming: HEOS Built-in, Apple AirPlay 2, Bluetooth, Spotify Connect, internet radio

Roon Compatibility: Roon Tested

Internet Radio: TuneIn

Wireless Networking: Wi-Fi

Wired Networking: Ethernet

Bluetooth: Audio reception and headphone retransmission with volume control

Tuner: AM/FM

Listening Modes: Stereo, Direct, Pure Direct

Remote Control: RC-052SR

App Control: Marantz AVR Remote, HEOS

Voice Assistant Compatibility: Amazon Alexa, Google Assistant, Apple HomePod/Siri, Josh.ai

Custom Installation: IR and IP control, HDMI diagnostics

Display: Front-panel circular OLED

On-Screen Interface: Graphical setup assistant; English, Spanish, French

Firmware Updates: Network or USB

Power Management: Eco mode, automatic power-off, sleep timer

Power Consumption: 210 W

Standby Power Consumption: 0.2 W

CEC Standby Power Consumption: 0.5 W

Network Standby Power Consumption: Less than 2 W

Dimensions (H × W × D): 4.3" × 17.4" × 14.7" (109 × 442 × 373 mm), excluding antennas