Since the STR-DA5300ES emerged like a bit of a damp squib in 2007, Sony has made some serious upgrades and enhancements to create a bigger, bolder and much more dynamic-sounding STR-DA5400ES.

See those socks over there? They were blown off.

The crashing mechanical chaos of Transformers (Blu-ray) explodes into the room with searing speed, and the percussive impact goes deep, deep down and keeps digging.

Full-throttle performance

Using full-range floorstanding speakers all-round, leaving the sub purely for LFE duties, the DA5400ES's control throughout the frequency range is as thrilling as it is addictive. It's so tight and focused it hurts; action movies are a full-throttle adrenaline ride from start to finish.

Dialogue is crisp and clean and, unlike some of its peers, it manages to avoid making all male actors sound like they are auditioning for Carlsberg adverts. The top-end is refined and polished, keeping high-frequency effects on the glassy edge without falling into sibilance. Brilliant.

First impressions

So, great sound, fantastically featured, great value and easy to use? Well, not exactly. Out of the box, plugged into my speakers in their usual places and using the auto-setup system, the sound was fair but not spectacular.

The open-air scenes in Transformers didn't elicit the mass of spatial detailing one would like, and the whole movie seemed rather trapped into the confines of the room. It was all a bit thick in the middle and lacklustre – just how I recall the predecessor, in fact.

There is little manual adjustment of the DCAC EQ set-up and the initial run damn near tuned my sub out of existence.

Stiff competition

Then there is the features count. at around £1,500, the sony is battling with some very hot competition including Denon's AVR-4308A, Pioneer's SC-LX81 and Onkyo's TX-NR906.

All three are Ethernet-networked machines, which the Sony isn't, with web-radio tuners and USB ports for audio files. All three claim more power than the Sony, the Denon adds DAB radio, the Pioneer hash AIR Studios tuning and THX Ultra2 specification, and the Oinker brings ISF video calibration. It would be all too easy to take the STR-DA5400ES at face value and put it into an 'also-ran' category.

But that would be doing it a huge disservice. While Sony has forgone Ethernet connectivity in favour of proprietary DM Port implementation – and other features – the company has clearly spent a lot of R&D wonga where it counts: in component quality and digital technology.

Beneath the surface

Compared to its predecessor, the DA5300, there are significant changes beneath the lid. The amplifier block has been revised to reduce resonance in the heat sink, important as that whole area tends to be microphonic.

The previous AVR used lead-type transistors – that's to say, transistors with legs. With the 5400, these have been replaced with surface mount transistors. This, says Sony's design team, has done two things: audio quality has been improved and vibration has been minimised.

According to lead designer Masaki Sato, the amplifier's bandwidth has been boosted by up to seven per cent. 'For the user,' explains Sato, 'this means that the sound-staging, the feeling of atmosphere created by the receiver, is better. When you listen to a movie soundtrack, it's much more immersive than it was before.'

Elsewhere, a completely new high-tech DSP block is married to 32bit DSD (SACD-speed) DA converters and a host of clever jitter-reducing circuitry. A bunch of features, including Digital Legato Linear, are aimed at improving the sound of formats like good old Dolby Digital and standard DTS, and the latest DCAC calibration and set-up system comes supplied with a stereo mic.

And good news for PJ owners: there are two simultaneous HDMI outputs alongside the six inputs.

Precise setup

Audio grunt is supplied by Sony's Wideband Power Amp version 3. And therein lays the enigma of the STR-DA5400ES's sound.

The power amplifiers have an effective bandwidth that stretches way, way out to the western spiral arm of the sound spectrum in the region of 160kHz. While even bats would have trouble hearing frequencies that high, the effect down in the audio-band is to reduce the onset of phase rotation to over 16kHZ, where the human lughole is least sensitive to it.

The result is a sound that is incredibly linear over the main audio-band, which I have found makes where you put your speakers and what angles they are at absolutely vital. Think of it as a family saloon versus a race car. The average suspension and compromise set-up of a road car means you can drive fairly sloppy and still get from A to B, whereas get the precise suspension geometry of a race car wrong and its 'hello ambulance' pretty swiftly. The Sony demands serious care and attention in speaker set up, and gets better and better with every speaker upgrade.