Probably the greatest and most beneficial single change possible with belt driven tools of most types is the removal of the old V drive belt(s), and the installation of correctly sized link belts. Vibration levels drop instantly, and a lot. Regardless of the quality of a solid circle V belt, the material will always take a set when it remains still for a period of time. This accounts for the start-up clunk of many table saws, including the three belt cabinet saw models.
Link belts are simple, made of separate links that are a twist fit together to get any particular size needed.
Link belts absorb vibration in a way standard belts cannot: the links move slightly within each other, dissipating the forces that create vibration. They also are more flexible in general than are V belts, and they do not take a set over time. Vibration may not be a real ogre breathing over your shoulder, but it does reduce accuracy in working with wood. The mass of cast iron in better woodworking tools is there in large part to reduce vibration. Add a link belt--and for some contractor's saws, a set of machined pulleys--and you automatically reduce to almost nothing the problems created by vibrations that are transmitted (or even created) by the V belt.
Link belt sections are made of urethane elastomer reinforced with woven polyester fabric for durability. Each link, depending on brand, adds 3/4" or 7/8" to overall belt length. Individual sections are about 2" long. The links can be assembled by hand, but using a needle nose pliers makes the job easier on the fingers. Threading a belt around pulleys, and then joining the ends, is often simpler than any other method of belt installation. If the belt is too long, slip off a link. If it's too short, add a link.
For most hobby woodworking machines, 1/2" (A/4L) is the right width.
Link belts may prove useful on table saws, jointers, drill presses and any other shop tool that is belt driven.
One quick check that tells you (at least in part) whether or not link belts will be helpful in your case is to remove the drive belt, and start the tool. Very often, you'll find the motor by itself is whisper quiet, meaning problems start at the belt, though it's often possible that the saw or jointer or drill press has bearing or other problems further down the list of problems. If the motor runs whisper quiet with no belt and no load, then any vibration problem has to originate somewhere else. The simplest check is belt replacement. If vibration remains low after the link belt is installed, you're in great shape. If vibration and noise return, you need to check further. Remove the blade, and restart the motor (on jointers and drill presses, you simply have to figure that the bearings are gone or going). If the saw vibrates a lot with no blade, and with a link belt, then you're having, or are about to have, major problems in the arbor and arbor bearing area. Check the arbor for run-out. If that's OK, then replace the arbor bearings if the manufacturer of your saw doesn't carry the bearings any longer, check with a local bearing supply house. Most bearings used in tool construction are standard sizes, and are easily found at such suppliers--usually at lower cost than the tool manufacturer may give you. It is often possible to get a step or two up in bearing quality at very low cost.