When it comes to HD, flatscreens offer better visual performance than old-style CRT displays. But they do have a generic weakness - audio performance. The feature that makes flatscreens so attractive is what impedes them when reproducing sound. Flat panels have quickly turned from luxury to commodity items.

The net effect is that an external solution, based around separate speakers, is a prerequisite if premium audio quality is important. This is the target market at which Tannoy's Arena HighLine 500 system is aimed.

An evolution of last year's highly- regarded original Arenas, this HighLine set comprises a tall, floorstanding column, and a shorter column that can be used on stands, shelves or attached to the wall, in a vertical orientation; or, in the almost identical centre version, horizontally. These models can be mixed and matched at will, and are technically closely related, with an identical drive unit configuration in each case.

The system tested here consisted of two towers and three satellites for rear- channel and centre-channel duties, plus a subwoofer, which is also unusually discreet, with a shallow front-rear depth, despite specifying large (30cm) drivers. Inventively, it has spike points on every side. This allows you to choose a placement which is most effective, musically, in your listening room.

Tannoy's subwoofer includes a 500W Bash digital amplifier featuring a switch-mode power supply and a power amplifier configuration that offers a combination of digital and analogue power amps. The input can be passed through an adjustable low-pass filter when dealing with a full bandwidth signal, or unfiltered if working with an input that's been pre-filtered, for example when connected to the LFE output of a home cinema amplifier.

Unconventional

The remaining 500 series satellites are far from conventional. The key drive unit in each case is a 100mm Dual Concentric, a Tannoy proprietary technology in which an ultra wide-band tweeter is buried in the mouth of the bass/midrange unit, which acts as an acoustic guide for the high-frequency output.

DCs are tricky to design and optimise, but have the benefit that all frequencies appear to come from a single point in space, which has a number of psycho-acoustic benefits. Because the bass cones are quite small, a second unit with the same cone diameter, but limited to low frequencies, supplements the output.