1. WDADU: John Myung
Same reasons mentioned by others, his playing just pops up there. His bass lines are very cool and different to what JP is doing. We haven't seen any other DT album with JM playing this way.
Honorable mention: John Petrucci
He was still developing his sound and technique at the time, but we can see his influence as primary songwriter/lyricist and the songs definitely have a guitar-oriented feel.
2. IAW: James LaBrie
Performs flawlessly the crazy vocal lines he was given and made the band stand out and gain worldwide success.
Honorable mention: Kevin Moore
Huge step up in his playing from WDADU. With the exception of a couple spots where his patches sound dated (now), his performance is as good as it gets.
3. Awake: Mike Portnoy
I feel like Awake is the album where Mike developed the creativity to come up with amazing drum parts that made him the standard for prog metal drumming for over a decade. I think this is one of his best drum albums to date.
Honorable mentions: James LaBrie, John Petrucci and Kevin Moore
Sorry to pick three members here, but it had to be done.
James, again, proved he was the best fit for the band, having to sing in a much different and more agressive way than on IAW, and he totally delivered. Some of his best "early DT" moments come from Awake.
John pretty much drives the whole album with his massive guitar riffs and unreal solos (Voices an Lie, enough said
).
And Moore's work, while very different from what he did on IAW, is responsible for creating Awake's dark atmosphere, which is unique to this album and I completely love it. Just listen how he sets up the mood on tracks like LSOAD... perfection.
4. FII: John Petrucci
This album isn't one of their best, but JP's guitar playing isn't the reason why. He explored a completely different side of his playing, with jazzier solos like Trial of Tears or just pure feeling with songs like LITS, TAMP, etc.
Honorable mention: John Myung
The songs from this era have very cool bass lines by JM, his playing is super solid and spot on.
5. SFAM: Jordan Rudess
He came to de band and changed the keyboard game completely. Took the band to a higher technical level and challenged Petrucci to constantly up his game (and vice versa).
Honorable mention: John Petrucci
Like I just said, Jordan's style forced JP to get on an even higher technical level, and it shows here with all the crazy unisons and runs they do here.
6. SDOIT: Jordan Rudess
Again, Jordan gets the credit for making this album one of their best. He experimented a lot with different sounds and textures, and every patch he uses is perfect for every section of every song. His playing is pure magic through the whole album.
Honorable mention: Mike Portnoy
As with Awake, he got to create some of his best drum lines for SDOIT.
7. TOT: Mike Portnoy
Great drumming on this album. He played very aggressively and it gave the songs a lot of energy
Honorable mention: John Petrucci
Heaviest album demanded the heaviest guitar sound and playing, and he nailed it from start to finish.
8. Octavarium: James LaBrie
He had to cover a lot of ground with his vocals and performed perfectly on each song.
Honorable mention: Jordan Rudess
The first album he used more stuff than just keyboards (continuum and lap steel guitar), which worked really well, and also played THAT solo on the title track.
9. SC: John Petrucci
THE RIFFS!
no explanation needed here.
Honorable mention: Mike Portnoy
To me, the last GREAT drumming album by MP. Yes, he used his same old bag of tricks, but man, did he use it right.
10. BC&SL: John Petrucci
Everything with his playing is spot on. The solo work is excellent.
Honorable mention: Jordan Rudess
Very tasteful playing, he doesn't need to be in the front all the time, but he's doing an amazing job throughout.
11. ADTOE: Jordan Rudess
I remember he commented at the time that he had felt restrained with DT many times before, during the last couple years/albums (at the time), with Portnoy trying to stir the ship and musical direction. ADTOE felt like he got free again and played his tail off, like we hadn't heard him do in a long time.
Honorable mentions: John Petrucci and Mike Mangini
John for stepping up as the clear leader of DT and producing everything just by himself, and Mike because he took one of the hardest jobs on the biz and he nailed it.
12. DT: Mike Mangini
This is the ultimate Mike Mangini drumming album for me (probably untill DOT drops
). Say what you want about the snare sound here, no one can deny the mastery of the drum parts.
Honorable mention: John Myung
Showcased an amazing chemistry with Mangini, with some amazing bass/drums grooves and his overrall lines and tone are great
13. TA: James LaBrie
His best album vocally, he just does everything here. Flawless performance.
Honorable mentions: JP, of course, for coming up with the concept and producing this monumental project; and Jordan for writing everything along with Petrucci.
Phew, that was a long post