To get informed with the specs of the receivers, we suggest you read the Denon AVR-S640H and Yamaha RX-A870BL review. According to the results of our review, Denon AVR-S640H received 6.2 points out of 10 possible, and Yamaha RX-A870BL was rated 8.3 points. The release date of AVR-S640H is 2018, and RX-A870BL is 2017. This review shows us that the RX-A870BL is a better choice as a home AV receiver than the AVR-S640H.
For the built-in amplifier, the devices received different marks - 6 and 8, respectively, on a 10-point scale.
The number of channels is equal to the number of possible connected speakers. The Denon AVR-S640H supports 5.2-channels sound, but Yamaha RX-A870BL supports a 7.2-channels configuration.
RMS stands for the actual power of the receiver. The higher this value, the louder the sound can be produced. The differences between the models in terms of RMS power are significant - for the RX-A870BL this value is 100/8 W/Ohm, and for the AVR-S640H it is 75/8 W/Ohm.
|Stereo power (RMS), W/Ohm||75/8, 100/6||100/8|
|Output impedance, Ohm||8, 6||8|
|THD in stereo, %||0.08||0.06|
After reviewing the audio features of each model, we can rate the AVR-S640H 6 out of 10, and the RX-A870BL - 8.
Bi-amping is the amplification of one speaker with two amplifiers. This amplification method has a positive effect on sound quality. Bi-amping is possible on the RX-A870BL.
Most receivers now come with a microphone included. It is with the help of this microphone that the auto-calibration system functions, which adjusts the sound of the receiver to the room.
|Digital to analog converter (DAC)||192 KHz/32-bit||Burr-Brown 192 KHz/24-bit|
|Pure direct (straight)||✔||✔|
|Auto speaker calibration||Audyssey MultEQ||YPAO|
|Speaker A/B switching||✖||✖|
|Other audio features||Audyssey Dynamic Volume, Audyssey Dynamic EQ, Compressed Audio Restorer, Hi-Res audio||CINEMA DSP 3D, Compressed Music Enhancer, Virtual CINEMA FRONT, Extra Bass|
The connectivity of competitors in our comparison is markedly different, Denon AVR-S640H scored 7, and Yamaha RX-A870BL scored 8 out of 10.
Bluetooth connection is now one of the main communication protocols for the receiver's control or even music broadcasting.
DLNA is the perfect way to use your local cloud storage to stream movies and music directly to a TV. You can use the DLNA protocol only with Yamaha RX-A870BL.
|USB||1 (USB 2.0)||1 (USB 2.0)|
Now music streaming services are gaining more and more popularity. They allow users to listen to millions of songs by subscription.
|Apple Music (AirPlay)||AirPlay, AirPlay 2||AirPlay|
|Other streaming services||Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud||Deezer, TIDAL, Pandora, Napster, SiriusXM|
The presence of many connectors makes the receiver more versatile. But there are also narrowly targeted models, the number of connectors which are limited to a certain area of use. And when choosing their own receiver, users need to consider exactly your goals for using the receiver. For extensive connection, Denon AVR-S640H got 6 points, but Yamaha RX-A870BL received 9 points.
Denon AVR-S640H is equipped with 5/1 HDMI inputs and outputs, and Yamaha RX-A870BL has 8/2 HDMI inputs and outputs.
|HDMI ARC (Audio Return Channel)||✔||✔|
|HDMI eARC (Enhanced Audio Return Channel)||✖||✖|
|Digital content protection (HDCP)||HDCP 2.2||HDCP 2.2|
|Subwoofer output (LFE)||2||2|
|Headphone output||1 x 6.3||1 x 6.3|
|Optical digital input||2||2|
|Coaxial digital input||1||2|
|Phono (MM) input||✔||✔|
|Front panel connectors||USB, phones, setup mic||USB, HDMI, phones, setup mic, AUX|
|Multi channel preamp output||✖||✔|
The AV receiver is the heart of the home theater. And in this case, support for all current video formats ensures the best user experience, so it is very important to consider this when choosing a device. Video features of the AVR-S640H were rated 6 out of 10 against the 10 for the RX-A870BL.
Most of the AV receivers have a video scaling function, it is the process of reformatting the video signal to a higher resolution without losing the quality of the image. Upscaling the video signal resolution is possible with Yamaha RX-A870BL.
|HDR (High Dynamic Range)||✔||HDR10|
|4K signal pass-through||4K/60Hz||4K/60Hz|
|8K signal pass-through||✖||✖|
|HDMI signal pass-through||✔||✔|
|3D signal pass-through||✔||✔|
|HDMI pass-through in standby mode||✔||✔|
|Video conversion||✖||analog to HDMI|
|Analog to HDMI scaling||✖||✔|
|HDMI to HDMI scaling||✖||✔|
|Other video features||BT.2020, HLG||DeepColor, x.v.Color, HLG, BT.2020|
In terms of evaluating additional features, both receivers received a score of 10 out of 10.
|Voice control||Amazon Alexa, Google Assistant, Siri, Josh.AI||Amazon Alexa|
|App control||iPhone, iPad, iPod, Android||iPhone, iPad, iPod, Android|
|Display||colour OSD||colour OSD|
|Tuner||AM, FM||AM, FM|
|Auto power off||✔||✔|
|Graphical user interface (GUI)||✔||✔|
|Firmware update||network, USB||network, USB|
|Other additional features||IP Control, Web Control||has not|
As the center of a home media system, each multichannel receiver has an additional set of terminals for connecting the second set of speakers to create additional audio space in Zone 2 or even Zone 3 where audio can have the separate source.
|Multi-room zones||has not||2|
|Zone audio output||has not||speaker, preout|
|Zone HDMI output||has not||✔|
|Multi-room control||has not||MusicCast|
|Remote control input/output (IR)||0/0||1/1|
|DC trigger output (12V)||0||1|
Denon AVR-S640H got 5 points for the multichannel surround sound and Yamaha RX-A870BL got 7.
Dolby Atmos' particularity is that this is the object-oriented sound format, that is, each audio signal object is independently sounded and connected to its spatial position. Yamaha RX-A870BL can create 3D sound due to the Dolby Atmos support.
DTS:X is an algorithm used by the processor to create sound scenes, where sounds connected directly to objects rather than channels, and to determine the optimum sound output distribution in space. Surround sound with DTS:X is available on the RX-A870BL.
|Dolby (other)||Dolby Digital Plus, Dolby Pro Logic||Dolby Digital Plus|
|DTS HD Master||✔||✔|
|DTS (other)||DTS 96/24, DTS-HD, DTS-EXPRESS, DTS-Surround, DTS Neo:6||DTS-EXPRESS, DTS Neo:6 Cinema, DTS Neo:6 Music|