Getting the centre track just right can be tricky, writes Greg Borrowman.

A centre-channel speaker is important in any home theatre system, because when you're watching movies, more than half the dialogue is reproduced by the centre-channel.

Positioning the centre-channel correctly is equally important. If it is not placed directly above or below the TV, the actors' voices will appear to be coming from somewhere other than the screen. The problem is that locating the centre-channel correctly is often difficult. Your TV or screen may be too big, too small, too thin, or you may just not have enough room.

Australian speaker designer Hume L'Estrange, the founder of Betetec Industries, which manufactures Aaron speakers, has devised an inventive solution. He's split a normal centre-channel speaker into two parts and then built the two halves into the left and right-channel speakers of his Aaron Decor 200 speakers. Thanks to a quirk of human hearing, this fools your ears into thinking the centre-channel sound is coming from exactly halfway between the left and right speakers.

Mr L'Estrange says he decided to exploit this psychoacoustic trick primarily because it solved the problem of properly positioning the centre channel, and there was also a cost saving for consumers in not requiring a separate speaker cabinet.

In another first for an Australian loudspeaker design, the Aaron Decor D-200 front left and right speakers can be customised by adding custom-made grilles and side panels to match the height of your TV or video screen perfectly.

Mr L'Estrange says the grilles can be covered in a variety of standard colours or a fabric provided by the customer.

Betetec has brackets that can be used to mount the D-200s to walls, and can also be used to attach the speakers to each side of a swivelling TV panel.

For consumers who prefer the sound of large, floor-standing speakers and don't want a centre-channel near their screen, Betetec's Aaron D-400s also have an integrated centre-channel speaker.

Pump up the quality

Many people who would not dream of eating burnt food or drinking flat beer are listening to the musical equivalent. If you are loading CDs into your iTunes music library using the default settings of this Apple program, you are being short-changed, because the quality of the music copied at the program's default setting is low. The good news is that you can easily improve the sound quality by changing just one setting in the program. Here's what to do:

� Open your iTunes program

� Select Edit from the toolbar

� When the dropdown menu appears, click on Preferences

� Click on the Advanced tab

Once the Advanced screen appears, the Import Using heading will show AAC Encoder and the Settings heading will show High Quality-128kbps. Click on the Settings arrow and you'll see a further option: Higher Quality-256kbps. Select this option, then go back to the main iTunes screen. It is as simple as that.

Now all the CDs you load into your iTunes library will be converted at much higher quality and this will be reflected in the sound you hear through both your headphones and, if you connect your iPod to your hi-fi system, through your loudspeakers. The improvement in quality will be most evident through the speakers, especially at higher volume levels. The files you create will be slightly larger in size, so you won't be able to fit as many songs on your iPod as you could previously, but the difference is well worth it.

It is possible to generate even higher-quality digital files when loading CDs, but you should do this only if you are prepared to sacrifice a lot of playback time. Here's what you do: When you were changing the Settings menu to 256kbps you should have noted a Custom option at the bottom of the drop-down. Choose this, then follow the prompts and set the bit rate at 320kbps and the sampling rate at 48,000kHz. The sound quality will improve even further.

The problem with using this much higher rate is that it will more than double the size of the digital file, so you will be able to fit only half as much music on your iPod.