Having had an opportunity to test Yamaha RX-V6A vs Marantz STEREO 70s, I’d like to share my impression here to facilitate your choice of a new AV receiver.
The number of channels for receivers is different - 7.2 versus 2.2, respectively, for devices. In terms of power, there are differences, the RX-V6A has such a ratio W/Ohm - 100/8, while the STEREO 70s has a power of 75/8, 100/6. The value of total harmonic distortion is also different, and for the RX-V6A it is 0.06%, but for the STEREO 70s it is 0.08%. Each of the compared opponents supports Bi-amping. Both Yamaha RX-V6A and Marantz STEREO 70s can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
These units have the same Wi-Fi modules. Each of the receivers has a Bluetooth connector. Both devices can work with such Apple Music services: AirPlay, AirPlay 2. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Yamaha RX-V6A works with Deezer, TIDAL, Pandora, SiriusXM, Qobuz, but the Marantz STEREO 70s works with Deezer, TIDAL, Pandora, SiriusXM, Napster, SoundCloud, Amazon Music, Amazon Music HD, MOOD:Mix.
The quality of 4K/120Hz signal remains unchanged when transmitting from a source to a TV or projector via HDMI for both receivers. Signaling over HDMI in standby mode can provide the RX-V6A and the STEREO 70s. Each of the devices can increase the resolution of the incoming video signal. Each of the participants of the comparison has a Dolby Vision.
The number of HDMI inputs/outputs varies depending on the receiver, the RX-V6A has 7/1, and the STEREO 70s has 6/3. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is only supported by the RX-V6A. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. RX-V6A and STEREO 70s support the standard HDCP 2.3. Like most receivers, our models have a built-in phono stage for connecting a vinyl player.
Unlike the RX-V6A where 2 Multi zones is provided, the STEREO 70s works with 1 Multi zones. For voice control in the RX-V6A is used Amazon Alexa, Google Assistant, Siri, but in the STEREO 70s is used Amazon Alexa, Google Assistant, Siri, Josh.AI. There is an ECO mode in either AV receiver. The Yamaha RX-V6A and the Marantz STEREO 70s can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the RX-V6A. Only in the RX-V6A realized a DTS:X surround technology.