It makes sense comparing Onkyo TX-SR383 vs Yamaha RX-A8A because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Onkyo TX-SR383 has 7.2 versus 11.2 for Yamaha RX-A8A. Regarding power, then TX-SR383 has such a W/Ohm ratio - 100/8, 135/6 when RX-A8A has a power of 150/8. The THD is 0.09% for the TX-SR383 but 0.06% for the RX-A8A.
Characteristics of digital to analog converter (DAC) are different, 192 KHz/24-bit for TX-SR383 and 384 KHz/32-bit for the RX-A8A. Only the RX-A8A supports Bi-amping feature. The Yamaha RX-A8A can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. Only the RX-A8A supports Spotify. HDMI signal transmission in standby mode is implemented in each of the devices. The RX-A8A can scale the input HDMI signal, unlike the TX-SR383. Dolby Vision technology found support only on the RX-A8A.
The Onkyo TX-SR383 has 4/1 HDMI inputs/outputs versus 7/3 HDMI connectors of the Yamaha RX-A8A. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the RX-A8A. 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 RX-A8A. The RX-A8A has a built-in phono stage for connecting a vinyl player.
The TX-SR383 supports 2 Multi-room zones, versus 3 for the RX-A8A. An ECO mode is only available for the RX-A8A. The setup assistant will help you configure Yamaha RX-A8A.
Only the RX-A8A has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the RX-A8A.