If I absolutely have to choose
one for each:
Symphony No. 1 - Gustav Mahler
Symphony No. 2 - Jean Sibelius
Symphony No. 3 - Johannes Brahms (Though Beethoven comes pretty close, as could Bruckner, possibly.)
Symphony No. 4 - Anton Bruckner
Symphony No. 5 - Ludwig van Beethoven (Though Mahler is also pretty close: not close enough, however.

)
Symphony No. 6 - Gustav Mahler
Symphony No. 7 - Anton Bruckner
Symphony No. 8 - Anton Bruckner (Ack, it feels like Mahler deserved this spot; but the 8th is Bruckner's turf, through and through.)
Symphony No. 9 - Ludwig van Beethoven (But see below!)
Symphony No. 10 - Gustav Mahler (Not the 10th, however: the
9th, written tenth in a row,
counting "Das Lied". Yes, I had to cheat.

)
Though don't take this as "binding", by any means: it's 3:25 in the morning, I haven't slept, I'm trying to initiate the process of starting to begin going to sleep (

), and I'm just browsing around the forum, coming up with off-the-top-of-my-head lists.
