haha Bach - the thing is do you know why it has that effect on you? it works the same way as dance music does - the beat has a slightly faster tempo than your heart rate which causes it to increase! in baroque times (ie Bach's lifetime) the harpsichord was the instrument of the moment and so many composers wrote for harpsichord (initially, tho it may have been transferred to orchestra in later years) and on the harpsichord you can't play long notes, and therefore pieces for harpsichord tended to be faster. so there you go.
(metallica and the san fransisco orchestra has gotta be the best for just being totally epic!)
