The Onkyo TX-SR383 vs Marantz SR8015 comparison proves that these receivers have many common features.
A significant difference between the receivers in the number of channels, Onkyo TX-SR383 has 7.2 versus 11.2 for Marantz SR8015. Regarding power, then TX-SR383 has such a W/Ohm ratio - 100/8, 135/6 when SR8015 has a power of 140/8, 175/6. The THD is 0.09% for the TX-SR383 but 0.05% for the SR8015. Only the SR8015 supports Bi-amping feature. The Marantz SR8015 can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. Only the SR8015 supports Spotify. HDMI signal transmission in standby mode is implemented in each of the devices. The SR8015 can scale the input HDMI signal, unlike the TX-SR383. Dolby Vision technology found support only on the SR8015.
The Onkyo TX-SR383 has 4/1 HDMI inputs/outputs versus 8/3 HDMI connectors of the Marantz SR8015. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the SR8015. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The TX-SR383 supports the protection of digital content of the standard HDCP 2.2, versus HDCP 2.3 in the SR8015. The SR8015 has a built-in phono stage for connecting a vinyl player.
The TX-SR383 supports 2 Multi-room zones, versus 3 for the SR8015. An ECO mode is only available for the SR8015. The setup assistant will help you configure Marantz SR8015.
Only the SR8015 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the SR8015.