Hi-fi amplifiers and receivers are straightforward devices, built simply to make the best-sounding noises that their designers know how. They're generally not heavy on user features, because all non-essential circuitry inevitably degrades sound quality to some extent.

By and large you can tell which are the good ones because they are stripped down and minimalist in tone. They rarely have tone controls, DSP or other toys, and even more rarely are they the most powerful in their price class.

Home cinema amps are something else. Most of them receive radio broadcasts (and so become 'receivers'), often via the internet, in addition to FM, MW and sometimes DAB. But they have other purposes, too.

They are designed to handle a wide range of sources of different types, often in digital form from a Blu-ray player, and convert it into a multichannel feed via a spatial processor based on Dolby and/or DTS technology. It will usually be required to feed 5, 8 or even nine loudspeakers plus a subwoofer or two.

Onkyo

For a variety of reasons, the requirement to do more than simply amplify has become rampant; so much so that Onkyo, purveyor of the TX-NR3007 auditioned here, is working on a stripped-down model intended to put sound quality first, and which will have the absolute minimum of unnecessary trimmings.

Personally, I can't wait, but don't expect to hear more about it for a while. Meanwhile, this AVR has no such minimalist pretensions. It is best regarded as a toolkit for moulding the sound into your chosen pattern and, as I discovered, it's very powerful and flexible.

Challenging for the top

A 9.2-channel (count 'em) THX Ultra2 Plus receiver, the TX-NR3007 is second only to the top-of-the-range TX-NR5007. It has one fewer HDMI input, one less audio input (but you still get plenty of both) and a slightly simplified arrangement of power transformers.

There are three here: an open frame power transformer, and one each for the remaining audio and video circuits. Onkyo sells a simpler model too, this time with a single mains transformer, the £1,300 TX-NR1007.

THX Ultra2 Plus is an enhanced version of the familiar THX Ultra2, optimised for slightly larger rooms where the listener-to-main speaker distance is 4 metres or more (although less is okay, too), and with an enclosed 85 cubic metres or more – a really big room in other words.

It also has an enhanced volume control system called THX Loudness Plus, which enriches the ambient soundfield when listening at lower volume than the THX-specified level.

As for other highlights, the TX-NR3007 is said to be currently the only receiver available in this price-range with ISF (Imaging Sciences Foundation) video calibration. It allows the user to calibrate the receiver to the screen, independently of any calibration available on the display itself.

With ISF, parameters like brightness, hue, contrast saturation and gamma can be set individually for each video input. Elsewhere, HQV's powerful Reon VX processor can be used to upscale standard-def video – very effectively as it turns out – while audio conversion uses proprietary VLSC circuitry, 24/192 DACs with Texas Instruments jitter-reduction technology. Tasty.

Last but not least, the Onkyo is one of the few receivers capable of processing DSD (the file format of SACD) natively, without prior conversion to PCM.

The Onkyo's room calibration is handled by Audyssey's MultEQ. This takes an age to tune itself, and works in conjunction with Dolby Volume, and two Audyssey technologies called Dynamic EQ and Dynamic Volume that 'optimise the frequency response and dynamic range at all volume levels'.