An affordable AV receiver is always a good option to consider, so Sony STR-DH770 vs Pioneer VSX-S520 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Sony STR-DH770 has 7.2 versus 5.1 for Pioneer VSX-S520. Regarding power, then STR-DH770 has such a W/Ohm ratio - 105/6 when VSX-S520 has a power of 50/4. The THD is the same and is 0.09%.
Competitors' digital to analog converter (DAC) is identical to 192 KHz/24-bit. Only the STR-DH770 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. Only the VSX-S520 supports Spotify.
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 STR-DH770. 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. Of the two receivers in our comparison, HDMI CEC is present only in the VSX-S520. 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 not present in each of the AV receivers. The setup assistant will help you configure Pioneer VSX-S520.
Only the VSX-S520 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the VSX-S520.