Denon has unveiled its latest proposition: the AVC-A1HD: a networkable THX Ultra2 amplifier (with both 802.11b/g wireless wi-fi and Ethernet) which threatens to take no prisoners.

Basically, it's a big (and I mean big, though in the grand scheme of things, not inordinately heavy) monolithic multichannel amp capable of fielding a vast raft of analogue and digital sources, and routing the sound at high power to a variety of different speaker arrays.

Versatile amplifier

It includes HD-compliant video processing, comes complete with an automatic setup feature, is fully network-aware, and will handle internet radio, not forgetting virtually any iPod/MP3 player you can think of.

This makes it - on paper at least - a very flexible core for any multi-source system, and this versatility is complemented by the promise of high-quality playback when used with multichannel movie soundtracks from Blu-ray and DVD.

The A1HD uses the latest version of Realta's SXT2 HQV i/p and upscaling chippery, with the key interface being HDMI v1.3a, which provides a framework for TrueHD and DTS-HD MA lossless processing; spangly features like automatic lip sync, DeepColor, boosted bit depth and extended xvYCC colour space support; and upscaling of all video inputs to 1080p.

The amplifier acts as an active HDMI repeater with six inputs, two outputs (although I'd have liked more, to be honest) and 1080p24 passthrough (ie without further processing). The other features of v1.3a will act as a powerful hedge against future video-related format developments.

200W power

This monster also offers no less than 12 audio preamplifier inputs and two outputs. Those who don't have a full 9.3 surround system in their cinema room (that'll be most of us) will perhaps be interested in the Denon's ability to power up to four zones simultaneously from different sources, subject to some limitations about the number of channels available in the secondary zones.

Output power is quoted at 200Wper channel with two channels driven simultaneously: but as usual there is some cross-coupling through the power supply which limits power output when more channels are driven simultaneously.

In our labs we measured real world two-channel performance at 200W, dropping to 158W-per- channel with five channels driven.

As you can see, then, this remains a prodigiously powerful amplifier. Inside lurks a massive torroidal transformer-based power supply, and a dual-mono symmetrical circuit layout.There's also extensive attention to internal reinforcement to minimise distortion.

Spreading sound

The Denon features the highest-spec available version of Audyssey MultiEQ-XT room equalization technology, which involves the use of a supplied calibration microphone, gathering results from a number of locations in the listening room, to give a relatively uniform spectral spread of sound.

Perhaps surprisingly for those new to Audyssey room equalization, this works remarkably well, based on experience not just with this amplifier, but also with similarly-equipped earlier models.

Wave pattern

In some ways the AVC-A1HD is disappointingly conventional. At first sight, and despite the humanizing effect of the wave-like front-panel profile, the Denon looks quite similar to previous high-end amplifiers from the brand, the preceding AVC-A1XV for example.

It also lacks the latest iteration of THX Ultra2 Plus post processing, with all the benefits that hardcore AVphiles will appreciate. However, the back panel has been reorganised for greater intelligibility, and in a clear break with tradition, the old block-graphic onscreen interface has been replaced by something slightly more contemporary- a Graphical User Interface (GUI) no less.

It will take some learning, but with its extensive use of submenus and text labels, you should certainly find it more useable and informative.

Takes some getting used to

You'll also find in the box two remote control handsets, one for the main listening zone, another slightly simpler one for a second zone.

The primary handset is an electroluminescent design with a touchscreen interface, but display illumination is rather dull, and the graphics are not especially clear. To my mind, some previous Denon designs have been more impressive.

In common with other amplifiers of its ilk, the AVC-A1HD takes a while to get accustomed to. It's a big, hairy monster, which consumes a lot of shelf space, and whose height will make it impractical in some surroundings.

The GUI is undeniably a step in the right direction, but it exacts a price in the amount of acclimatisation required. This is an amplifier which seems purposely calculated to scare grannies, small children and household pets, and which, even for the initiated, represents a significant investment in learning how to drive the beast.

If you like your amplification to be plug-and-play, this is probably not the model for you.

Denon's restrictions

Of course, there are some minor in-built restrictions that limit the amount of control manipulation that is possible.

For example, you cannot use this Denon to convert HDMI signals back to analogue (component, S-video and composite video routes are available, though it's anyone's guess why you might want to, especially with so many HDMI inputs available), and when using component video there is no onscreen display in zone two.

Note also that surround back speakers in addition to standard surrounds are required for some of the THX modes - Ultra 2 Cinema, Music mode and Games mode - and a broadband connection (wired or wireless) is obviously a necessity for internet radio if you're willing to put up with the sound-quality hit involved.

Powerful but disciplined performance

This is a powerful amplifier which cruises with the greatest of ease and transparency at high SPLs, and which does justice to some very fine speakers that are not ordinarily easy to please - Yamaha's Soavo range for example, or Monitor Audio Precisions.

It's also a great match for high-definition software. I hooked the model up to a Toshiba HD DVD player - a kaput technology I know, but not quite up there with VHS - and was knocked out by its Dolby TrueHD performance.

The Denon sounded a little more civilised and disciplined than I had expected from previous similar pairings, but without noticeable loss of fluidity or dynamics. There is no reason to expect Blu-ray to be any worse.

I also used the 720p HD signals from a Sky+ box as an input for the Denon, and again the results were strikingly impressive, with pristine, well-resolved fine detail and few motion artifacts that could not be attributed to the Sky+ box or transmission itself.

Great with SACD

As for music, Denon is, like its numerous competitors, keen to accommodate the iPod generation.

The AVC-A1HD therefore includes algorithms designed to 'restore' missing signal components in compressed audio files - MP3 and similar - but don't expect too much from bodges of this kind.

The rule is that once musical information has been lost, it can never be accurately reinvented, though the feature does provide a listening experience that may be interpreted as more pleasing.

Still, there is no matching sense that resolution has been enhanced, a key problem with lossy audio files, and data-reduced 256k AAC recordings from a tame iPod did not end up sounding like the real thing.

It does a great job, however, with CD and SACD, using a Denon DCD-SA1 SACD player as source.

Impressive multichannel audio

Like other top-end Denon AVRs, this one includes Cat5-style Denon Link, which allows you to patch in multichannel SACD signals in raw digital form from a similarly-equipped disc player, for digital-to- analogue conversion by the amplifier.

This is the connection of choice should you have the right source equipment, as it's incredibly stable and clean.

It lacked something special that the brand's own two-channel PMA-SA1 is able to provide, but that's is a much more expensive proposition with few of the bells and whistles that the AVC-A1HD offers.

I think it's fair to say that the AVC-A1HD represents a step forward in the evolution of the multichannel amplifier, one based partly on technology from the brand's superb AVP-A1HD/POA-A1HD pre/power flagship, but there remains a question if its a step far enough.

It is a natural for multichannel audio and video, of course, and with its high-end video processing, it is an obvious good fit with Blu- ray.

A superior amp

As a tool for purist audio purposes it's equally well-placed. I suspect that there's a significant crossover market for those interested in high-quality multichannel audio, who also want top-grade music from their stereo recordings.

In many ways the Denon could hardly be a better match, especially given its ability to 'improve' compressed audio files, and its ability to work with iPods and the like. Yes, there is much to like about this new Denon.

It remains to be seen, though, if the AVC-A1HD has the commercial stamina to fight off both the slavering hounds of Onkyo's considerably cheaper but similarly-specified flagship models, and the undoubted finesse of Yamaha's THX Ultra 2 Plus DSP-Z11 and Pioneer's upcoming SXC-LX90.

However, there's no doubt this is a superior piece of AV hardware.