Let's make the Denon AVR-X6400H versus Onkyo TX-NR686 comparison. According to the results of our review, Denon AVR-X6400H received 9.4 points out of 10 possible, and Onkyo TX-NR686 was rated 7.2 points. The release date of AVR-X6400H is 2017, and TX-NR686 is 2018. After comparison, it will become clear that among these two devices, the AVR-X6400H is more suitable for the role of the heart of home theater system.
For the built-in amplifier, the devices received different marks - 10 and 7, respectively, on a 10-point scale.
The number of channels is equal to the number of possible connected speakers. The Denon AVR-X6400H supports 11.2-channels sound, but Onkyo TX-NR686 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 AVR-X6400H this value is 250/6 W/Ohm, and for the TX-NR686 it is 165/6 W/Ohm.
|Stereo power (RMS), W/Ohm||140/8, 250/6||165/6|
|Output impedance, Ohm||8, 6||6|
|THD in stereo, %||0.05||0.08|
After reviewing the audio features of each model, we can rate the AVR-X6400H 10 out of 10, and the TX-NR686 - 9.
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.
Speaker A/B switching allows you to change between the main and sub speaker set. Denon AVR-X6400H can work with the main and additional set of speakers - and switch between them.
|Digital to analog converter (DAC)||AK4458 384 KHz/32-bit||VLSC 384 KHz/32-bit|
|Pure direct (straight)||✔||✔|
|Auto speaker calibration||Audyssey MultEQ XT32||AccuEQ|
|Speaker A/B switching||✔||✖|
|Other audio features||Audyssey Dynamic Volume, Audyssey Dynamic EQ, Audyssey LFC||Advanced Music Optimizer, Theater-Dimensional, Hi-Res audio|
The connectivity of competitors in our comparison is equal and was rated 8 out of 10.
Bluetooth connection is now one of the main communication protocols for the receiver's control or even music broadcasting.
|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, TuneIn Radio|
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-X6400H got 10 points, but Onkyo TX-NR686 received 8 points.
Denon AVR-X6400H is equipped with 8/3 HDMI inputs and outputs, and Onkyo TX-NR686 has 7/2 HDMI inputs and outputs.
HDMI eARC is the next step in the development of audio return channel technology, which works in conjunction with HDMI 2.1. Using eARC provides the highest sound quality for home audio systems. HDMI eARC is available only on Denon AVR-X6400H.
|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||2||1|
|Phono (MM) input||✔||✔|
|Front panel connectors||USB, HDMI, phones, setup mic, AUX||HDMI, phones, setup mic|
|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-X6400H were rated 9 out of 10 against the 7 for the TX-NR686.
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 only with Denon AVR-X6400H.
|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||HLG||DeepColor, x.v.Color|
In terms of evaluating additional features, the AVR-X6400H got 10 points, but the TX-NR686 has 7.
Only the Denon AVR-X6400H has the ECO mode.
|Voice control||Amazon Alexa, Google Assistant, Siri, Josh.AI||Google Assistant|
|App control||iPhone, iPad, iPod, Android, Amazon Kindle||iPhone, iPod, Android|
|Tuner||AM, FM||AM, FM|
|Auto power off||✔||✖|
|Graphical user interface (GUI)||✔||✔|
|Firmware update||network, USB||network, USB|
|Other additional features||IP Control||IP Control|
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.
|Zone audio output||speaker, preout||speaker, preout|
|Zone HDMI output||✔||✖|
|Multi-room control||HEOS App, Denon 2016 AVR Remote||Onkyo Controller app, FlareConnect|
|Remote control input/output (IR)||1/1||0/0|
|DC trigger output (12V)||2||0|
Denon AVR-X6400H got 9 points for the multichannel surround sound and Onkyo TX-NR686 got 7.
Auro 3D gives a bit more versatility than Dolby Atmos or DTS:X and provides a hemispherical sound and enables a receiver to produce 3D sound stages. Only the Denon AVR-X6400H has Auro-3D on its feature list.
|Dolby (other)||Dolby Digital Plus||Dolby Digital Plus|
|DTS HD Master||✔||✔|
|DTS (other)||DTS-ES, DTS 96/24, DTS-EXPRESS, DTS Surround||DTS-ES, DTS 96/24, DTS-HD, DTS-EXPRESS|