Evolution of a theme tune

The people at DrWhoGuide.com have collected together the theme music to Doctor Who over the years, all the way back from the 60s. Its interesting to hear how the same piece of music has changed over the years.

From 1963 to 1981, it was much the same arrangement with only minor differences.
William Hartnell's theme
Patrick Troughton's theme
Jon Pertwee's theme
Tom Baker's theme

With the arrival of Peter Davison in the role, we have this stark change of pace.
Peter Davison's theme
Colin Baker's theme

This one's my personal favourite, used from 1987 to the end of the classic series in 1989.
Sylvester McCoy's theme

In the 1996, the show was momentarily revived by the Americans in TV-Movie form.
Paul McGann's theme

Finally, the current version, from the 2005 series.
Christopher Eccleston's theme

Wasn't that fun!