Thing is, as far as I'm concerned, DT never used to have a "signature sound". The first DT album I heard was I&W, back in 1992. The first song on that album is "Pull Me Under", the second is "Another Day". I can't think of another band that has put two completely different songs back to back on an album like that, a heavy, thrashy metalfest followed by a soft, almost jazz-fusion ballard. With a saxophone. And if that wasn't weird enough, the third song is "Take The Time", which sounds like Rush, Yes and the Red Hot Chilli Peppers playing different songs in different keys and tempos at the same time.
Awake sounded nothing like I&W, and FII sounded nothing like either of those. The simple fact is, I listened to every new DT album with a sense of wonder - could music really be like this?
For my money, DT can/could do anything they want. World music? A classical symphony? A bluegrass album? Bring it on, I'm sure it would still have the innovation, musicality and attitude that make it DT.
But they do seem to have stopped trying. For me, Systematic Chaos was the first album that, while it has some moments of brilliance, doesn't really bring anything new to the party (although both TOT and 8VM lacked something). I've loved every album since, but they just don't compare IMO. The changes to their live shows haven't helped either.
I strongly believe there are two sorts of DT fan - those of us of a certain age who've followed this band for 20 years and really want to see a return to the glory days when being a DT fan really made you feel part of something special, and younger metal-head kidz, who really only want something dumb and more and more metal. DT are more frightened of losing the kidz than they are of losing the long-time fans.
This is evidenced in two ways, firstly the song-writing itself, where even the quiet songs have to have metal bits (everytime I hear the intro to The Bigger Picture I wish it started with the piano part - the only reason I can see for that loud intro is that they don't want the metal kidz to think "OMG a ballard" and switch off. That intro just sceams "don't worry kidz, it'll get loud again in a minute".
And secondly, audio quality. For a few albums now, DT seem to have embraced this "everything louder than everything else" approach to their albums. For those of us with quality top-end hi-fis, their recent albums are just a wall of noise. I would love to see DT's next album be a proper audiophile release, but it ain't gonna happen.
So while DT never used to have a signature sound, I guess they do now. And that is very restricting for a band that a great many fans would follow anywhere. So I reckon the next DT album is going to sound exactly like the last few. Like the man said - Here comes the new boss, same as the old boss. I'm sure the metal-head kidz will love it.