Keith Merrows tone since he got his Rhodes Colossus, Killswitch Engage from End of Heartache to now (pre End was better music, post End is better sound )
And a tone that I've always loved since before I started playing guitar was Cradle of Filths tone on Midian... I can't get that creamy sound out of my head!
Lately it's been Daron Malakian on the Toxicity album. He's just got a good mix of raw heaviness and clarity. He's not necessarily a favorite player of mine, but i dig that tone and i find myself with a similar tone when i shape mine.
Dimebag, Robb Flynn/Phil Demmel, and Kerry King/Jeff Hanneman, but I've always tried to stay away from copying anyone's tone, because part of being a musician is finding your own voice via your guitar tone.
Besides, almost everyone is already ripping off Dime's tone now...
Aaron John Gregory of Giant Squid, the band that also renewed my efforts to find a cellist.
Mike Schiedt of Yob
Hearing these bands literally changed my life and made me reexamine the way I was approaching my art, and as a guitarist it was their guitarists whose sound and styles had the most influence on me. The tone I'm still chasing is heavily influenced by all four.
I guess I owe some credit to Andrew Southard (formerly and once again) of Giant Squid for making me want to start keys again, too!
I ride Ron Jarzombek's dick...constantly. Love his tone. I know it's mostly due to his extremely tight/clean playing. If I remember correctly, he still uses the Johnson J Station to record then adds effects later on.
I can't shape my tone to match all of these but, I love them for unexplainable reasons.