An affordable AV receiver is always a good option to consider, so Yamaha RX-V581 vs Pioneer VSX-S520 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha RX-V581 has 7.2 versus 5.1 for Pioneer VSX-S520. Regarding power, then RX-V581 has such a W/Ohm ratio - 115/6 when VSX-S520 has a power of 50/4. The THD is the same and is 0.09%.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 192 KHz/24-bit for RX-V581 and 192 KHz/24-bit for the VSX-S520. Only the RX-V581 supports Bi-amping feature. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. The Apple Music service is implemented on considered devices: AirPlay. Spotify can be used on each receiver. The RX-V581 can work with the audio stream from Pandora, JUKE, and the VSX-S520 can receive a content from Deezer, TIDAL, TuneIn Radio.
These units support HDR technology. Compared AV receivers retain the quality of 4K/60Hz signal when transmitting from a source to a TV or projector. HDMI signal transmission in standby mode is implemented in each of the devices. The VSX-S520 can scale the input HDMI signal, unlike the RX-V581. Dolby Vision technology found support only on the VSX-S520.
Each receiver has 4/1 HDMI inputs/outputs. The HDMI Audio Return Channel (ARC) feature supports both devices. Unfortunately, HDMI eARC is not available on monitored devices. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. Both models support the standard HDCP 2.2. The VSX-S520 has a built-in phono stage for connecting a vinyl player. A voice control is not available. An ECO mode is only available for the RX-V581. Both RX-V581 and VSX-S520 can be configured using the Setup assistant.
Both devices have support for Dolby Atmos multichannel audio format. The surround sound technology DTS:X is supported by devices under review.