Denon AVR-X3400H has 7 channel and Marantz SR7015 has 9 channel amplifiers. Denon AVR-X3400H delivers 105 W (8 Ω, 20 Hz - 20 kHz, 2 channel driven) and Marantz SR7015 delivers 125 W (8 Ω, 20 Hz - 20 kHz, 2 channel driven) and they both have stable performance at 4 Ω load. Since 2016 all receiver manufacturers have dropped front wide channel support and these models are no exceptions.
Denon AVR-X3400H supports 4K passthrough up to 60p and Marantz SR7015 supports 8K passthrough up to 60p. Denon AVR-X3400H can do 4K upscaling up to 60p and Marantz SR7015 can do 8K upscaling up to 60p. Denon AVR-X3400H supports HDR10, Dolby Vision and Marantz SR7015 supports HDR10, HDR10+, Dolby Vision.
High-dynamic-range (HDR) video has greater dynamic range than standard-dynamic-range (SDR) video with brigter whites and deeper blacks. HDR10 was announced on August 27, 2015, by the Consumer Technology Association and uses the wide-gamut Rec. 2020 color space. It sends static metadata via video stream to the TV which calibrates its screen brightness and color according to that. HDR10 supports up to 1000 nits of brightness and 10-bit color which corresponds to 1024 shades of the primary RGB colors.
Dolby Vision and HDR10+
Dolby Vision and HDR10+ are both updates to HDR10 by adding dynamic metadata that can be used to more accurately adjust brightness levels up to 10,000 nits maximum brightness on a scene-by-scene or frame-by-frame basis and support up to 12-bit color depth (4096 shades of RGB) and 8K resolution.
Dolby Atmos and Dolby Surround upmixer
Denon AVR-X3400H and Marantz SR7015 support Dolby Atmos with its Dolby Surround upmixer. The Denon AVR-X3400H can be configured upto 5.1.2 channels using internal amplifiers and the Marantz SR7015 can be configured upto 7.1.2 or 5.1.4 channels using internal amplifiers or upto 7.1.4 channels by adding 2 channel external amplifier.
Dolby Atmos is the first cinematic audio format in which sounds exist as individual entities, called audio objects. In Dolby Atmos, any sound - the helicopter, a car screeching around a corner, a melodic bird call - can exist as an independent audio object, free of channel restrictions. They can be precisely placed and moved anywhere in your room, including overhead, to flow above and around you in three-dimensional space. Through the use of audio objects, overhead sound, and all the richness, clarity, and power of Dolby sound, Dolby Atmos turns your room into an amazing place for entertainment. You'll feel like you're inside the action, in ways you've never experienced before.
Dolby Atmos for the home represents every sound in the original cinema mix as an audio object. Extensions to the Dolby Audio™ codecs, along with an advanced scalable algorithm, allow Dolby Atmos to be delivered via Blu-ray Disc and streaming media. A spatially-coded substream is added to Dolby TrueHD or Dolby Digital Plus. A Dolby Atmos audio/video receiver (AVR) adapts the cinema experience to your home theater from seven speakers to as many as 34 in 24.1.10 configuration, recreating the original artistic concept. The format supports up to 128 simultaneous independent audio objects in a mix for rich, realistic, and breathtaking sound. It recreates the director's original concept through descriptive metadata to provide customized playback for home theater and delivers sounds above you through overhead speakers, special upward-firing Dolby Atmos speakers, or a Dolby Atmos enabled sound bar.
If the content is not mixed in Dolby Atmos then the Dolby surround upmixer will expand the audio to all channels including ceiling speakers. The upmixer has replaced the Dolby Pro Logic II family with improved upmixing algorithms.
DTS:X and Neural:X upmixer
Denon AVR-X3400H and Marantz SR7015 support DTS:X with its Neural:X upmixer. The Denon AVR-X3400H can be configured upto 5.1.2 channels using internal amplifiers. The Marantz SR7015 can be configured upto 7.1.2 or 5.1.4 channels using internal amplifiers or upto 7.1.4 channels by adding 2 channel external amplifier.
A technique used in DTS:X is similar to the one used in Dolby Atmos. Instead of a fixed number of channels, DTS:X defines object locations from the listener in polar coordinates. An a/v receiver then dynamically renders sound according to the current speaker configuration. The speaker layout employed by DTS:X is the sum of Dolby Atmos and Auro-3D. It has standard 7.1 channel base layer, a 5 channel height layer above the base layer on the front and side walls, and 3 rows of speakers on the ceiling.
DTS Neural:X is an upmixer that can take non DTS:X content and upmix it to the DTS:X speaker layout. It has replaced the DTS Neo family with improved flexibility.
Auro-3D with its Auro-Matic upmixer
Marantz SR7015 supports Auro-3D and its Auro-Matic upmixer out of the box or after free firmware update. Auro-3D is an immersive 3D audio format developed by the Belgium-based company Auro Technologies. It consists of three layers of sound - surround, height and overhead ceiling. The base horizontal layer uses 5.1 or 7.1 format, the height layer is on top of the base layer and its information is extracted from the standard 5.1 surround PCM carrier. The a/v receiver decoder then extracts this information during playback. In home cinema Auro-3D comes with different listening formats - Auro 9.1, Auro 10.1 with added Top Ceiling channel ("Voice of God"), Auro 11.1 with added Front Height Center channel, and Auro 13.1 with added Left Rear Surround & Right Rear Surround channel. Auro-Matic upmixer takes non Auro-3D sound and upmixes to the current speaker configuration.
Current Feedback Topology
Marantz SR7015 features Current Feedback Topology which is a well known, Marantz’ original circuit technology. The Current Feedback amplifier technology fits perfectly with the high requirements set for Super Audio software providing wide-bandwidth, high-speed reproduction. The impedance at the Current Feedback point is limited resulting in a very low phase shift. Marantz receivers and amplifiers equipped with Current Feedback can keep the phase compensation via Negative FeedBack (NFB) to a minimum, resulting in high through-rate, excellent transient response and superb sonic transparency for the full bandwidth. Unlike conventional Voltage Feedback amplification, the Current Feedback amplification makes the power amplifier in-sensitive to difficult loudspeaker loads.
Marantz SR7015 features exclusive Marantz HDAM (Hyper Dynamic Amplifier Module) technology found on their Reference Series components. Marantz developed its own discrete circuit boards to replace standard IC's. These HDAM's consist of discrete surface mount components with short mirror image L/R signal paths. Those devices are doing exactly the same thing as the Op-Amps, but outperform the regular IC Op-amps dramatically in terms of the Slew Rate and reduced noise level, resulting in a much more dynamic, accurate and detailed sound. Over the years Marantz developed different types of the HDAM to improve quality and to fit to the special requirements of a product category like CD or amplifier.
Compressed music enhancement in Marantz SR7015 is done by Marantz’ MDAX2 technology. The use of compressed audio files like MP3, Windows Media™ Audio or AAC is getting more and more popular. The audio quality of these compressed files however is less than the original lossless files that are on a CD, especially lacking the higher frequencies and affecting the lower frequencies which make the audio image less wide and deep. The Marantz Digital Audio Expander 2, also called M-DAX2, recalculates the outputted frequency range. This enables you to get a more detailed and clearer sound.
Denon AVR-X3400H can be connected to internet using ethernet cable or built-in wi-fi adapter. It can also connect to bluetooth devices via built-in bluetooth adapter. The Receiver works with Amazon Alexa and supports[y] AirPlay 2. It has 8 HDMI inputs with HDCP 2.2 copy protection. There are 7.2 channel analog pre-outs for external amplification.
Front panel has HDMI and USB inputs.
Marantz SR7015 can be connected to internet using ethernet cable or built-in wi-fi adapter. It can also connect to bluetooth devices via built-in bluetooth adapter. The Receiver works with Amazon Alexa and supports[y] AirPlay 2. It has 8 HDMI inputs with one 8K input with HDCP 2.3 copy protection. There is a phono input with built-in phono stage for connecting the cartridge output of the turntable directly to the Receiver. There are 7.1 multi-channel analog inputs and 11.2 channel analog pre-outs for external amplification.
Front panel has HDMI, USB, Composite and L/R Audio inputs.