Also, DVDs usually don’t provide an isolated music channel. Almost certainly there’ll be speech and sound effects and varying volume levels.
Absolutely. Many people have the misconception – and I once thought this too – that the isolated music is hidden in the rear channels or something.
This is true only for some relatively low-budget DTV films and TV shows. It is very rare for this to be the case for full-length feature films. Surround sound is meant to bring the sound environment to life in a realistic way, and sometimes that means a character is shouting behind you or an explosion is rocking your rear speakers.
There ARE such things at isolated scores on DVDs – but they have always been rare and some even have sound effects mixed in anyway.