Denon AVR-X6400H review

This Denon delivers a captivating home cinema performance. Tested at £2300

What Hi-Fi? Verdict

A terrifically composed, articulate and confident AV receiver that delivers a captivating home cinema performance for the price


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    Excellent clarity and detail

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    Fluid dynamics and rhythms

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    Accurate timing

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    Refined character

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    Exhaustive features and connections


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    Some might prefer a bigger, more muscular sound

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Spending over £2000 on an AV receiver is no frivolous matter. Good thing, this Denon AVR-X6400H – one of Denon’s top AVRs for 2017 – takes its job seriously, then.

Not only is it decked out with all the features and technology you’d expect from a modern home cinema amplifier, it also delivers excellent performance that easily makes it worth spending serious money on.


Imagine the refined £500 Denon AVR-X2400H, but with a bigger, bolder and more confident presentation.

That’s the gist of this Denon AVR-X6400H – it offers plenty of poise, control and subtlety along with a healthy dose of punch and surround-sound prowess.

It’s a surprisingly musical amplifier, with a wonderfully fluid sense of dynamics that keeps you hooked on every word and action unfolding on screen.

Voices, in particular, are a high point for this Denon amp. Play the opening scene from Guardians of the Galaxy Vol. 2 and varied tones of voices from all characters are communicated wonderfully.

It’s not just about delivering crisp detail and solidity; the nuanced and solid-sounding Denon imparts the humour and sarcasm behind every line of dialogue.

MORE: Guardians of the Galaxy Vol.2 – 4K Ultra HD Blu-ray review

The AVR-X6400H balances the frequencies well, too. Dialogue is enunciated clearly, and it doesn’t get swallowed up amidst the explosive havoc occurring around the main cast.

Objects and aliens are thrown about, and the nimble-footed 6400H has no problem tracking every aspect across the surround field. As expected, it sounds bigger and more spacious than its smaller £500 sibling. It’s an immersive performance, with or without the Dolby Atmos soundtrack activated.

There’s a sweetness to the refined top end that, while delivering the sharp crack of shattering glass in Fantastic Beasts and Where To Find Them, doesn’t make you wince.

MORE: Fantastic Beasts and Where to Find Them - Blu-ray review

Equally, low end performance has enough depth to render the action scenes in any film exciting.

Some might prefer a touch more grandness and outright power to those rumbling explosions, but we’re impressed by the 6400H’s ability to deliver the subtleties – if not the last scintilla of attack – of such scenes.

With its focus on control, grace and agility rather than all-out power and muscle, the 6400H is much more a gymnast than a bodybuilder.

Take the tightly choreographed fight scenes in John Wick 2 – they need speed and subtlety just as much as heft, and the Denon’s masterful control over every element keeps things edge-of-your-seat tense and compelling.

MORE: John Wick: Chapter Two 4K Blu-ray review

Its fluid rhythm and snappy sense of timing means the Denon amp is a decently musical performer, too.

System of a Down’s B.Y.O.B. requires more aggression and grunt than this refined amplifier is comfortable giving, but the Denon’s articulate and precise character suits Nine Inch Nails’s This Isn’t The Place beautifully - it ramps up the tension in the song while keeping every musical strand organised.

Just remember to set the amp to ‘stereo mode’ when listening to music via CD or over Bluetooth for a more rhythmically precise and focused presentation.


We’re not surprised to see the AVR-X6400H dressed as yet another burly, rectangular box – it’s nearly impossible for an AV receiver to be anything but – but the amp is solidly built and reassuringly hefty.

The brushed metal fascia looks smart too, and we like the flap hiding all the extra inputs and buttons on the front panel.

The 6400H is available in black or silver finishes, and it features a clear, informative display and big, chunky remote. We still bemoan the lack of a proper backlight, but the remote becomes second nature once you get used to the layout.

The buttons are responsive, as are the two large dials on the amp for changing inputs and volume.

MORE: Best home cinema amplifiers 2017

Setting up the Denon correctly is crucial: it comes with a mic for auto calibration, and can optimises its sound to your room’s acoustics and speaker configuration.

You can tell the amp exactly how many and what type of speakers you have – including up to four Dolby Atmos channels – and the resulting measurement is pretty much spot-on.

We’d still recommend diving into the manual speaker settings to double-check and fine-tune the numbers further if needed. Happily, Denon’s menus are nicely laid out and easy to navigate, so there's no need to be daunted even if you’re an AV newbie.

MORE: Dolby Atmos – What is it? How can you get it?


The AVR-X6400H features 11 discrete channels of amplification, which means you can have a 7.1.4 Dolby Atmos set-up without needing any extra boxes.

It also supports DTS:X, and Dolby Vision HDR is compatible right out of the box. HLG support is due imminently, via a firmware update.

All eight HDMI inputs (and three outputs) are HDCP2.2 certified, meaning they will play Ultra HD 4K and HDR content in their full glory.

MORE: Dolby Vision - everything you need to know

Along with the generous complement of HDMI ports, the 6400H comes with multiple analogue and digital connections, so those with lots of legacy kit are well catered for. It even has a MM phono input for turntables.

On the streaming side, the wi-fi-equipped Denon supports high-resolution streaming up to 24bit/192kHz and plays DSD files too.

You can also stream from smart devices using Bluetooth and AirPlay, while the 6400H has native support for Spotify Connect, Tidal and Deezer.

And as with all of 2017’s Denon AV receivers, the 6400H comes equipped with the company’s proprietary HEOS multi-room technology.

MORE: Best home cinema deals – Blu-ray players, AV receivers, projectors and more


Denon has gone to great pains to ensure anyone buying its £2300 AV receiver isn’t left wanting when it comes to the latest film and music playback technologies.

But extensive features aside, what really impresses us is how articulate, rhythmically precise and musical this AV receiver sounds. It’s punchy enough and fully exciting, but we love how it gives importance to the subtler aspects of sound quality.

A terrific performer, this Denon AVR-X6400H would be a worthy addition to virtually anyone's home cinema room.

Read all our Denon reviews

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