Interesting

[EpsilonX]

I think it's interesting to hear how this band has changed throughout the years

1989:
http://www.youtube.com/watch?v=79R4MrqGhWc

1992:
http://www.youtube.com/watch?v=C5sg8heGdyk

1994:
http://www.youtube.com/watch?v=VD7OdyY1js4&feature=relmfu

1997:
http://www.youtube.com/watch?v=a_Cv1QmZ_ks

1999:
http://www.youtube.com/watch?v=3TdJE-9xVrg

2002:
http://www.youtube.com/watch?v=SSX86zPnUkY

2003:
http://www.youtube.com/watch?v=mA6Jf4pRmp8

2005:
http://www.youtube.com/watch?v=TheGJeZUf_U

2007:
http://www.youtube.com/watch?v=EkF4JD2rO3Q

2009:
http://www.youtube.com/watch?v=GipraonNlNo

[EpsilonX]

Some pics

1985:
http://upload.wikimedia.org/wikipedia/en/5/51/Dream_theater_in_1985.jpg

1989:
http://upload.wikimedia.org/wikipedia/en/7/72/Dream_1989.jpg

1992:
http://userserve-ak.last.fm/serve/_/5623471/Dream+Theater+dt1992.jpg

'90s:
http://2.bp.blogspot.com/_jOmJne9MsKg/TUW9Okhu-JI/AAAAAAAAAgs/aEj7w4tjkMo/s1600/dream-theater2830.jpg

2005:
http://www.clevelandleader.com/files/Dream_theater_live_in_Parigi_2005.jpg

2011:
http://t2.gstatic.com/images?q=tbn:ANd9GcQUy_Q5OL3P9pw_0cSybAH0RgLkNKtHp 9TCQs0BKHSQXuIo6jk_hQ&t=1

[Synge]

Their sound has definitely changed over the years. Yet, their ass-kickery remains unchanged.

[EpsilonX]

I think the most drastic change in sound was from the first album to around metropolis part 2, after that they kinda leveled off.