Fine speed adjustment on Empire 698 ?

I had same situation on my Empire 598. Tighten the adjustment nut on the adjustable motor mount bolt, so that the drive pulley is slowly moved closer to the platter. (Drive pulley closer to platter=slower; farther from platter=faster.) Periodically, I time a song or two and compare to listed track times. Haven't done so recently, but about a month ago I was able to adjust so that the drive pullet was fairly close to the platter, and on several tracks roughly 4-6 minutes long the 'table was only 2-3 seconds fast, consistently. Best!

I had an Empire 598 turntable for many years, and the speed adjustment method (like that described by Kr4) was satisfactory.

I was unable to make any adjustment to affect the speed of mine when I had one. It ran slow, so I put some two-part epoxy on the pulley and "lathed" it smooth and to the correct diameter with sandpaper to achieve the correct speed.

Most Empires, afaik, had crowned pulleys and a screw adjustment on one of the motor mounts to shift the belt on the pulley. A crude but effective speed adjustment.

A more elegant and $$$ alternative is a VPI SDS controller.