From source, through home theatre receiver, to speakers… the three-stop path to high definition sound

Just like an old-fashioned stereo, your high definition sound system consists of three parts: a source of the sound, an amplifier, and a loudspeaker system. Precisely what constitutes those parts has changed a lot over the years.

Three steps to high definition sound

The source of the sound

High definition sound comes from HDTV broadcasts and from several different kinds of disc. For HDTV you need some form of HDTV receiver, of which there are three categories. Your TV may already have one built in, and that could be plenty good enough. Just remember that to get the best surround sound from your TV, you will need to connect it to a home theatre receiver using optical audio cable (see the GadgetGuy tip below).

An inexpensive HDTV receiver does basically the same job as one built into a TV. This is useful if your TV doesn’t have one built-in, or you are using a front projector (since these never have TV tuners). More commonly you will want a HD PVR – a personal video recorder – such as a Tivo media device or Foxtel IQ2 box. A PVR has inside it a computer-style hard disk drive for recording and storing TV shows, and allows you to time shift programs for watching at times more convenient to you.

For discs, HD sound can come from Blu-ray, DVD Video, DVD-Audio, Super Audio CD (SACD) or games from Xbox and Playstation. Both the Xbox 360 and the Sony Playstation 3 consoles provide full surround sound of the highest quality, really adding that all-important sense of immersion in a game.

Blu-ray discs can potentially offer the highest quality HD sound available, but not all do. After all, many older classic movies originated with only mono or stereo soundtracks. Nonetheless, most movies made in the last two or three decades, when released on Blu-ray, come with the highest quality sound treatment that they’ve ever enjoyed.

DVD-Audio and Super Audio CD offer sound quality very nearly as good as the best of Blu-ray, but these days it is hard to find discs for either formats. Meanwhile, the good old DVD often includes exceptional Dolby Digital or DTS surround sound.

A Blu-ray player will also play regular DVDs, but it won’t play either DVD-Audio or Super Audio CD. If you want to explore those formats, you will need a DVD player that supports them.

The centre of it all

At the centre of your high definition sound system will be a home theatre receiver. This decodes the digital sound held within the broadcast or on the disc into the music and voices you hear. It switches between the different audio-video sources you have available, and processes the sound so that it works best in your room and with your speakers. And, equipped with multiple amplifiers, it is also the power that ‘drives’ all those speakers. So important is the home theatre receiver that we look more deeply into its role in Home theatre receivers – HD sound central.

Speakers making sound

The most personal choice for your high definition sound system will be the loudspeakers. They will largely determine the final sound quality, and whether the system meets your tastes. But they have to fit into your room as well. Normally you need five speakers to truly deliver surround sound (some new technology can reduce the number you need) and a subwoofer to deliver the clean bass required for those movie explosions. You can read more about these in the Loudspeaker options for high definition.

These choices that need to be made when selecting speakers can be simplified by considering packaged systems. These may have the home theatre receiver and loudspeakers and subwoofer combined in one large carton. Some also have a DVD player built into the home theatre receiver part of the system, or even a Blu-ray player.

For the best overall performance from your home theatre system, we recommend spending roughly the same amount on your source, receiver and speakers as you are willing to spend on your TV. That way the picture and sound will be in balance with each other, rather than one coming at the expense of the other.

GadgetGuy tip – optical audio output

If you have a modern TV with a high definition digital TV tuner built-in, chances are it will have an optical audio output. If you run an optical cable from this to one of the optical inputs on your home theatre receiver, then you can enjoy the highest quality sound broadcast by the TV station. Some TVs will convert Dolby Digital sound to CD-like stereo PCM, eliminating the potential for full high definition surround sound. But check your TV’s manual and its menus, and chances are there is a way to switch it back to Dolby Digital. That way, if a program is broadcast with full 5.1 channel surround sound, your receiver will be able to decode it and deliver it into your room.