Pros & Cons

Denon AVR-X2400H

Pros

Has built-in Wi-Fi and Bluetooth modules. Therefore, you can access numerous online resources including thousands of internet radio stations.
The AirPlay technology lets you stream music from your iOS device.
Dolby Atmos and DTS:X technologies are able to create clear and natural sound.
The multi-channel stereo mode works for every video source.

Cons

Problems with audio during HDR playback.
The LCD lights may start to flicker or stop lighting up at all.

Denon AVR-X4000

Pros

7 in and 3 output channel with the 235 W of the maximum power per channel.
The operating temperature is not high.
The device can set up presets for your favorite internet radio sites.
A great remote controller with the text that can be read by seniors.

Cons

Menus and the manual provided can be quite confusing.
It has some issues with ARC cables (usually, no sound output).

Denon AVR-X1400H

Pros

Supports HDR and Dolby Atmos.
Great Upscaling via HDMI
I have found that voice commands via Alexa work perfectly.
I downloaded a digital version of the remote controller to control it via smartphone.
This receiver is relatively small.
The receiver is flexible and easy to use. Firmware updating is easy and it adds new functions.
The application is reliable and it has many functions.

Cons

If you want to connect it to a 4K TV with HDR you need to unlock this ability by pushing some button combination on the receiver itself.
The main interface is awful. The main categories and menus are mixed and controversial.

Specifications

Groups

Built-in Decoders
Signal Processing
Connector Type
Media Content Source
Additional Features
Amplifier
Sound Features
Audio Formats
Connectivity Interfaces
Dimensions
Functions
Power Device
Built-in Display
Radio
Clock
General

Specification	Denon AVR-X2400H	Denon AVR-X4000	Denon AVR-X1400H
Built-in Decoders
Dolby Surround
Dolby Digital Plus
Dolby Atmos
Dts:x
Dolby True Hd
Signal Processing
Hdmi Pass-through	up to 4K	up to 4K	up to 4K
Upscaling Via Hdmi	up to 4K	up to 4K
3d Pass-through
Video Conversion/scaling	HDMI to HDMI scaling, analog to HDMI up conversion	HDMI to HDMI scaling, analog to HDMI up conversion
Connector Type
Hdmi Outputs	2	3	1
Hdmi Inputs	8	7	6
Coaxial Digital Inputs	1	2	1
Optical Digital Inputs	2	2	2
Phones	1	1	1
Av Inputs	2	2	has not
Usb	1	1	1
Subwoofer Outputs	2	2	2
Coaxial Digital Outputs	has not	has not	has not
Optical Digital Outputs	has not	has not	has not
Media Content Source
Usb-host
Network
Bluetooth
Additional Features
Audio Return Channel (arc)
Apple Air-play Support
Advanced Sound Retriever (asr) Technology
Three-zone Capability
Smartphone Remote Control
A-b Speaker Switch
Dual-zone Capability
Pure Direct Mode
Auto Power Off
Bi-amplifying
Amplifier
Output Impedance Per Channel	6 Ohm, 8 Ohm	6 Ohm, 8 Ohm	4 Ohm
Output Power Per Channel	125 W, 95 W	125 W, 165 W	80 W
Total Output Power	500 W	735 W	560 W
Total Harmonic Distortion	0.08 %	0.08 %	0.08 %
Frequency Response	20 Hz-20 kHz	20 Hz-20 kHz	20 Hz-20 kHz
Sound Features
Surround System Class	7.2 channel	7.2 channel	7.2 channel
Surround Sound Effects	Cinema EQ. Loudness	Audyssey DSX	Dolby Surround
Audio D/a Converter	24-bit/192-kHz	24bit / 192kHz	32bit / 192kHz
Digital Content Protection	HDCP 2.2	HDCP 2.2	HDCP 2.2
Audio Formats
Apple Lossless
Aiff
Aac
Wma
Wav
Mp3
Flac
Connectivity Interfaces
Ieee 802.3u
Ieee 802.3
Wi-fi
Bluetooth
Dimensions
Dimensions	13.3 x 17.1 x 6.6 inches	14.9 x 17.1 x 6.6 inches	13.3 x 17.1 x 5.9 inches
Functions
Network Audio Player
Internet Radio
Digital Player
Power Device
Standby Power Consumption	0.1 W	0.1 W	0.15 W
Operational Power Consumption	185 W	670 W	430 W
Built-in Display
Colour	black	black	black
Type	fluorescent	fluorescent	fluorescent
Radio
Preset Station	56	56	40
Tuner Bands	AM/FM	AM/FM	AM/FM
Tuner Type	digital	digital	digital
Clock
Sleep Timer
Built-in Clock
General
Brand	Denon	Denon	Denon