The Marantz Stereo 70s is a slimline two-channel stereo receiver that combines Marantz’s established amplifier engineering with modern HDMI switching and network streaming in a chassis standing just 110mm tall. It sits within Marantz’s current range below the MODEL 40n integrated network amplifier and alongside the Cinema 70s AV receiver, distinguished by its dedicated stereo-only signal path. Where the Cinema 70s handles full 7.2-channel surround processing, the Stereo 70s strips the architecture back to two channels, directing all amplifier resources into a focused stereo presentation with dual subwoofer outputs.
Amplifier Section
The power amplifier stage is a discrete Class AB design rated at 75 watts per channel into 8 ohms (20Hz–20kHz, 0.08% THD), rising to 100 watts into 6 ohms. It employs Marantz’s Hyper Dynamic Amplifier Modules (HDAM) — proprietary discrete current-feedback circuits that replace conventional integrated-circuit op-amps in the signal path. The amplifier section achieves a signal-to-noise ratio of 98dB (IHF-A weighted) in Direct mode, with a frequency response extending from 10Hz to 100kHz.
A Pure Direct mode bypasses tone controls and video circuitry to shorten the signal path for critical listening. The unit supports speaker impedances from 4 to 16 ohms and provides four speaker terminals arranged in an A/B configuration, allowing two pairs of speakers to be driven independently or simultaneously.
HDMI & Video
Six HDMI inputs are fitted, three of which support 8K/60Hz and 4K/120Hz passthrough. A single HDMI output with Audio Return Channel (ARC) connects to a television. Video processing includes upscaling from 1080p and 4K sources to 8K resolution, with support for HDR10, HDR10+, HLG, Dolby Vision and Dynamic HDR. HDCP 2.3 ensures compatibility with current copy-protected sources. Gaming features include Auto Low Latency Mode (ALLM) passthrough, Variable Refresh Rate (VRR) and Quick Frame Transport (QFT). HDMI passthrough in standby mode allows the television to receive a signal without fully powering the receiver.
Analogue & Digital Inputs
Three analogue line-level inputs are provided alongside a dedicated moving-magnet phono stage with a sensitivity of 2.5mV and RIAA equalisation accurate to ±1dB from 20Hz to 20kHz. Digital connectivity includes one optical and one coaxial input, plus a front-panel USB Type A port for playback from storage devices. The USB input handles hi-resolution formats up to 192kHz/24-bit (FLAC, WAV, ALAC) and DSD at 2.8MHz and 5.6MHz. An AM/FM tuner is built in.
Streaming & Network
HEOS Built-in provides access to streaming services including Spotify Connect, Amazon Music HD, TIDAL, Deezer, Napster, SoundCloud, TuneIn internet radio, and Roon. Apple AirPlay 2 is supported natively. Bluetooth connectivity includes a re-transmit function for wireless headphone listening with independent volume control. Both Wi-Fi and Ethernet connections are available for network integration. The Marantz AVR App (iOS and Android) provides full control from a smartphone or tablet.
Multi-Room & Smart Home
The HEOS multi-room platform is integrated, enabling the Stereo 70s to participate in a whole-home audio system alongside other HEOS-compatible devices. A single multi-room zone is supported with its own source selection (HDMI, optical/coaxial, network, USB and analogue) and pre-amplifier output. Voice control is available through Alexa, Google Voice Assistant, Apple HomePod and Josh.ai. Additional control options include IP, web interface and IR flasher input.
Outputs
A 2.2-channel pre-amplifier output is provided for connection to external amplification or powered subwoofers, with two dedicated subwoofer outputs. A multi-room analogue output and a multi-room digital output extend the system into secondary zones.
