Articles and whitepapers

The Latest in Home Cinema Sound (19/4/2006)

By Robin Dyer, Dolby Laboratories

HD is suddenly everywhere. HD-ready screens are in the shops and HD services are launching all across Europe, with Sky's service set to launch in the UK. Next-generation disc media are being discussed in the newspapers. However, high definition entertainment is not just about the picture. High-definition pictures certainly provide a sharper, clearer and more involving image, but without surround sound, the emotion and ambience of the entertainment experience just isn't the same.

As a consumer, if you are buying a home cinema system, you want that cinema feel. If you are watching films in surround sound, you want to become part of the on-screen action, hearing every window shatter, feeling every explosion, and experiencing bullets flying past you. And it's not just movie content we're talking about here either - all forms of entertainment are now being produced with 5.1 surround sound including computer games and TV programmes, including sport, series such as 24, nature documentaries and live music shows. We are truly in the process of moving from a stereo world to a 5.1 world.

Friends enjoying the home cinema experience

In addition, with the introduction of next-generation disc formats, custom installers will be able to offer their customers bit-for-bit perfect reproduction of the studio master, and/or even more channels of sound for an even more immersive and exciting experience. For custom installers, this offers a great opportunity to help customers have a great entertainment experience.

The latest developments

In order to best enhance the visual improvements in home entertainment, two new complementary audio technologies for high-definition entertainment have been introduced. Probably the biggest impact on the audio in next-generation disc formats will come from the high quality and studio audio performance of Dolby TrueHD. This provides a bit-for-bit reproduction of the master, always producing the best quality available with up to 7.1 channels of sound on the new HD disc formats. This ensures that the viewer always hears exactly what the director intended when the film or programme was created.

But some applications cannot meet the requirements of bit-for-bit audio. Bandwidth may be an issue, as it is for HDTV, or multiple soundtracks may need to be carried on disc more efficiently. Dolby Digital Plus is included in both next-generation disc formats enabling quality stereo, 5.1 and 7.1 tracks to be carried at low bit rates, making it very attractive for HD broadcasts and IPTV. The attraction of this format is its ability to carry audio at low bit rates for additional features and commentary tracks, along with hearing- and visually-impaired services.

What does this mean for installers?

In order to accommodate these developments and future-proof your clients' systems, you should be suggesting an install of 7.1 speakers with the capability to extend to more channels in the future. Although no 7.1 content is currently being created, using Dolby Pro Logic IIx, any audio, whether a stereo or 5.1 track, can be extended to 7.1 channels to create a more seamless surround sound experience for the consumer.

There are certain factors to bear in mind when specifying and installing a home cinema system. As installers know, the quality of the components you use can affect the overall performance of the system. Generally the more you spend, the better the quality of sound. Cabling also makes a difference. It is not worth just buying the cheapest cables possible as this will detract from the end result. It is also worth considering the acoustics of the room in which you will be installing the system. Panelling can be used to deaden rooms which sound too 'bright' or 'tinny' and with a bit of thought and ingenuity, this can be done without giving the lounge, for example, the look and feel of a recording studio!

Speaker placement is also important. Speakers should be placed as close as possible to ear-height and should not be blocked by furniture or curtains. If the room contains seats with high backs or arms which are likely to block the sound delivery to the client's ears, you will need to think about how to overcome this. You will find more detailed guidance for speaker setups for different systems and different shaped rooms at www.dolby.com/consumer/home_entertainment/roomlayout.html.

Suggested positioning of speakers for 5.1 surround

These are just general guidelines to assist you in getting the best out of the system for your client. You will find there are certain movies or music tracks that sound brilliant in surround sound because they have been mixed so well - it's all a matter of personal taste. 'Concert for George' is a great example of a music DVD which has a beautiful 5.1 mix, and really takes advantage of the capabilities of 5.1, or alternatively films such as 'The Lord of the Rings', 'SpiderMan' and 'The House of Flying Daggers' have great sound sequences.

Looking to the future

As home entertainment progresses, there is plenty to think about. Content creators may start to produce their content with 7.1 or more channels. Even though 7.1 is the top end at the moment, it could increase to 13.1 channels or more in the future. Dolby TrueHD will offer bit-for-bit audio reproduction of the studio master, taking audio to the highest level and offering the enthusiast a really attractive experience. Home servers, where all content is stored on an entertainment PC, will give the consumer the opportunity to download new content as they want it and then stream it wirelessly to every room in the house.

With all these advances in home cinema surround sound, custom installers have a great opportunity to really question their clients on how they use entertainment and ensure their solutions fit the client's lifestyle. Consumers now have more power than ever before to control their entertainment experience and sound is crucial to the overall experience. The future is indeed bright - and now it sounds reassuringly exciting as well!

Robin Dyer is Marketing Manager Europe at Dolby Laboratories, creator of technologies for high-quality audio and surround sound.

www.dolby.com

Note: a disk of 5.1 clips is available for custom install professionals to test installations (although it is not for resale or for consumers) by emailing info@dolby.co.uk.