A problem that you sometimes get with basses is that the angle of the strings at the bridge is too acute. This is idiosyncratic to the way the instrument, in particular the neck setting, has been constructed. The steeper the angle of the strings at the bridge, the more downwards pressure is exerted on the table. This can affect the tone and may result in a bigger, brighter sound which could be desirable, but it can also cause problems if the table is old, thin and/or pressure sensitive. One may also be looking for a warmer, more open response for orchestra playing.
The solution to this problem, if it is a problem, is to raise the height of the bottom saddle. There are a variety of ways to do this and many players are now looking for an adjustable saddle raiser which allows them flexibilty, for them to have more control over the instrument's sound. I have just had a bass in for that job and came up with the solution pictured above. I am quite pleased with the result: a simple, what they might call here in Sweden "funkis", design. It is made from an old piece of fingerboard, fitted exactly to the existing saddle, which has two invisible screws holding it in place. It sits loosely and may easily be removed should the player wish to return to the original setting. The pressure from the string tension here is quite enormous which means careful attention to the fitting and form of the saddle is essential. The laws of physics and mechanics (vectors) must be taken into consideration. The tailwire is made of a very strong, non-elastic cord, tied with a simple knot which can also be easily adjusted. This will be necessary when switching between the different saddles.
Here you can see the adjusted string angles which sit nicely and evenly over the bridge.