The DDTS-100 manages all the current surround sound standards currently on the market for DVD and video. Firstly, there's Dolby Digital, the most popular standard. All the current DVDs are encoded in Dolby Digital 5.1. But the decoder also supports Dolby Digital EX. This is the first 6.1 standard currently available on the latest DVDs. At present, movies such as "Lord of the Rings: The Two Towers," or "Star Wars Episodes I and II" are already encoded in EX. The standard offers a separate sixth central rear channel. However, this involves a remix from 5.1 onward, prior to encoding the movie for a DVD. So it isn't really a separate channel but one that was added in the studio, something to give it a better image.

Now for the DTS. Fans of home theater systems are in total disagreement as to which is better, Dolby or DTS. Objectively speaking, DTS is slightly less compressed and so offers greater scope and better reproduction at low level. In practice, DTS 5.1 generally proves to be slightly better than the Dolby 5.1 track, with better positions and slightly more depth. It's hard to say, however, to what extent the standard is responsible and to what extent the encoding and mixing plays a part. Then there's DTS ES. This can be broken down into two standards, Discrete and Matrix, both of them managed by Creative's decoder. The DTS ES Matrix, like Dolby EX, matrixes the sixth channel for encoding the movie.

Finally, DTS ES Discrete is the only standard to offer a genuine, separate, mixed sixth channel, that was there from the creation of the movie. At present, very few DVDs are available that manage one or other version of DTS ES and the trend does not look as though there will be many of them. The only DVD in DTS ES Discrete that we found was "Haunted" with Catherine Zeta Jones, a rather average movie. In DTS ES Matrix, we found "Die Another Day" as well as "Gladiator" and "Chicken Run".