It makes sense comparing Denon AVR-S650H vs Denon AVR-S950H because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Denon AVR-S650H has 5.2 versus 7.2 for Denon AVR-S950H. Regarding power, then AVR-S650H has such a W/Ohm ratio - 75/8, 100/6 when AVR-S950H has a power of 90/8, 125/6. The THD is the same and is 0.08%.
Competitors' digital to analog converter (DAC) is identical to AKM 192 KHz/32-bit. None of the models support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Both models have the ability to connect to the Internet via WI-FI. Rivals from our review have Bluetooth support. The Apple Music service is implemented on considered devices: AirPlay, AirPlay 2. Spotify can be used on each receiver. Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, Mood Mix - all of these streaming services have found application in each of the models.
Both AV receivers support HDR10 technology (High dynamic range). 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 AVR-S950H can scale the input HDMI signal, unlike the AVR-S650H. The HDR standard - Dolby Vision is supported by these receivers.
The Denon AVR-S650H has 5/1 HDMI inputs/outputs versus 8/2 HDMI connectors of the Denon AVR-S950H. The HDMI Audio Return Channel (ARC) feature supports both devices. HDMI eARC is available in each model. 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 2.3. These compared receivers have a built-in phono stage for connecting a vinyl player. Supported voice control technologies are identical - Amazon Alexa, Google Assistant, Siri, Josh.AI. It is also worth noting that the ECO mode is presented in each of the receivers. Both AVR-S650H and AVR-S950H can be configured using the Setup assistant.
Only the AVR-S950H has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the AVR-S950H.