The Onkyo TX-SR706 is the company's first THX Select2 Plus receiver, whose main distinguishing feature from plain vanilla THX Select is THX Loudness Plus.

This transpires to be an umbrella term for two technologies.

One, called THX Multichannel Spectral Balancing, adjusts the frequency response of individual channels to counter the loss of presence at the frequency extremes, which is referred to a nominally 'flat' balance at a so-called Reference level – a smart loudness control in fact, which begs the question just how smart can any loudness control be?

Flashy features

The other THX technology, Dynamic Ambience Preservation, preserves spatial detail (aka imaging) when listening below the previously mentioned Reference Level.

In combination, they amount to the latest iteration of the THX standard, albeit in its smaller-room- dimension Select2 incarnation rather than the full-bore Ultra2.

The Onkyo also features Audyssey Dynamic EQ, which does broadly the same job as THX Loudness Plus. But where THX Loudness Plus is only available in one of the THX modes, the Audyssey counterpart is available in all non-THX surround modes.

But this is only the beginning of the Onkyo's capabilities, which by any standard represents a well- endowed package for the price. All video sources including standard-cooking quality DVD can be upscaled to 1080p using the Faroudja DCDi Cinema algorithm.

The Onkyo also includes a full implementation of the Audyssey room acoustic correction – even the obligatory microphone boasts Audyssey branding. It's a very effective process, which in the not-too-distant past was limited to Denon's receiver range.

Architectural flair

The all-important power amplifi ers share the internal architecture used on the top-of-the-range Onkyo receivers (a three-step inverted Darlington circuit from the 876), albeit with a reduced power output befi tting its lower price.

Other benefits include Onkyo's proprietary WRAT (Wide Range Amplifier Technology) and the improved isolation of pre- and power amp stages. Power output is rated at 160W-per-channel but this is to the slack IEC standard at 6Ω.

In real money, output is probably closer to 100-110W/channel, but in practice there's plenty of power for most reasonable circumstances with all channels under drive.

The preamp section, with its attendant video and DSP, is located near the front panel, and the power amps are locked close to the speaker terminals, which should and does add up to a cleaner, more sharply demarcated sound.

Wealth of connections

Naturally, iPod connectivity is built in, and so are decoders for DTS-HD Master Audio and Dolby TrueHD – which almost goes without saying.

Oh, and in addition to a raft of interconnections, the Onkyo boasts no fewer than four HDMI inputs and one output, all version 1.3a compliant, with included CEC control allowing data and instructions to piggyback the HDMI signals, reducing wiring complexity in some systems.

The SR706 is a receiver, so there's a built-in tuner. It's an FM/MW model with 40 presets, but there's no sign of DAB radio. From my point of view that's no disadvantage, given what I consider the poor overall sound quality performance of the format compared to FM, though I acknowledge DAB has its fans.

The 706 also has a high current power supply, to ensure that it can take transients in its stride, plus the ability to bypass unnecessary circuits (Direct mode and Pure Audio mode). It's also possible to 'bi-amp' the main stereo speaker pair for 'audio-first' applications.

Vivid sound

In use, the Onkyo TX-SR706 turns out to be hard to fault at its price level.