Classical composers, symphonies

As mentioned above, Shostakovich has a lot of big bold works.  His 5th Symphony is probably the most popular, and it's a doozy.  There's a great recording of the Royal Philharmonic Orchestra conducted by Charles Mackerras that I love, it's a great recording, huge dynamic range, and a phenomenal performance.  I believe this is the one, but I've long lost the original CD box so I can't remember what the cover art looks like:

https://www.amazon.com/Shostakovich-Symphony-No-Festive-Overture/dp/B000003YOH

Others to consider, especially if you're willing to wade into a bit of polytonality:

Charles Ives Symphony No. 2 (it may take a few listens for it to 'click')

Paul Hindemith's Symphonic Metamorphosis 

Rimsky-Korsakov's Scheherezade and Russian Easter Festival Overture are both pieces you'd likely enjoy.  They're program pieces and not symphonies, but still large orchestral works, and the Russians write for brass better than most anyone else.  

@lowrider57 

I've had good luck with Exton label recordings.  I haven't listened to everything they've put out by any means, but all of the ones that I have have been impressive.