so i checked the springs and they were no good..........broken..( )(butmy car was lower )anywho...i changed my struts and springs.and i drove the car around.but i am still getting the noise(like a knock) i swore that after i chaned the springs it would be smooth sailing...

Did you replace the upper mount rubber isolators for the springs along with all of the rubber parts for the shocks? The only other possibility that comes to mind is that the end of the control arm is hitting the inner fender - that will happen on hard bumps when the car is lowered more than 2" or so. Then there are the upper ball joints- if stock then the control arm itself is hitting something or if adjustable then the retaining bolt will hit in the shock tower. Beeen there with both of these sources of noise. Check that you have clearance between the end of the control arm and the inner fender and rubber liner. Last thought is that the bumpstops may be bad. Follow the instructions for the springs to cut them to the proper length-or leave them alone if you are not told to do anything. It is possible that you are bottoming out the shocks, mainly if the car is really low.

If all is well with these pieces, it is time to carefully check the CV joints and other chassis parts.