the level of production is so high these days that i could ring off a list 10 pages long of producers that have the potential to crank out a classic track...based on nothin but personal preference

Just Blaze...blows my mind sometimes the way he can flip a sample. No one can make a banger like him
DJ Premier...often imitated, never duplicated...the legend
9th wonder..lol gets brownie points for doin his shit on weak ass fruityloops
RZA ...still working and in terms of sampling, he was a revolutionary
Kanye...learned a lot from Just Blaze from the roc days and he combines that with a pop sensibility
Dre... dre never crowds his beats too much and sticks to the essentials..a piano riff, some 808's and a bassline...proven formula for success
Neptunes... insane drums...sounds so simple but the beat is always on point. With the right rappers (CLIPSE~!!!) ridin the beat you get tracks that get stuck in your head for weeks
Dan the automator/Prince Paul...lol just gonna combine em cause of hbms. Jazzy, laid back fun music
Hi Tek...great range and can make a beat for 50 and talib in the same day
Mannie Fresh...I guess you could call him the souths primo lol
Rick Rock...bay since before hyphy
ski beatz... primo before there was primo

bunch more but these are the ones whos beats I know will be fire before even hearing them (lol no timbo since timbo's been too busy jockin JT and nelly furtado to make a decent rap beat)