my dad and i just got ff strings made, one for his savannah and one for my custom longbow. bot of our bows got considerably louder and vibration became an issue.  the strings were made with ff serving and have beaver ball silencers on them.  i changed my dads to a 3-rivers tomahawk string today with spider leg silencers and it got quiter and shoots smoother.  i am going to try the sppider leg silencers on mine before i give up and take it off completely. i was told that i already had a ff string on it when we started.  the only changes on mine was that we made it beefier and doubled the ends and my dads also got 2 extra strands put in.  
what could have caused the vibrations and noise level changes?  do you thing the extra strands would have made a difference or the silencers.  i am not sure how many strands the tomahawk strings have, but i don't think it would be that much difference over the one's we had made. they are very nice and pretty strings, but if mine can't "shoot" itself out, i will go back to the old one.  any suggestions?

My first thoughts on your problem would be to check the brace height and the # of strands on the new strings. Tight nocks will cause lots of problems.

I would try to put 100 arrows through the string before I wrote it off.  Let it settle in.  Also, were are the silencers installed?  I like 1/4 of the way from nock to nock but each bow is different.

I can say from experience that on most of the recurves I have owned (and it has been many) that when I changed from fast flight to dacron endless loop, the bows became much quieter. They lose about 4-5 ft per second, but they are far quieter and smoother. This is especially true of my Black Widows. The rubber spider legs also work best for me.

i am going to keep mine on for a while.  i have tried the bh high and low and it is very loud and has a lot of vibration at al levels.  i am thinking that the extra added strands and support at the loops may be the culprit.  i have the original string and an extra, i may just put them back on for now.
if i can find someone that is reputable at making a good string, i will send them the string that was on it and get an exact replica made.  

sipsey river--do you get many 50lb savannah's?  if you get one let me know.

Are you using a flemish twist string?

There are several different fast flite type materials, and they don't all shoot the same.  Some are noisier than others.  However, I've found that all of them produce less vibration and usually less noise on longbows.  Tend to be a little noisier on recurves.  I'd look to the type and location of the silencers as others have already noted.  Also, might want to give them some time to shoot in.  I doubt that a few extra strands in the string or loops is the problem.  Good luck.

Quality of the string makes alot of difference also, get ahold of Chad at Champion bowstrings and have him make you one, hes made a bunch for me and you can sure tell the difference between a so so string a a really good one...hes made thousands of strings so he knows what hes doing..strand count shouldnt make a difference, but brace, silencer and nock position will...could your arrow now be slapping the riser if so move nock up or down, strand count will effect arrow spine to a degree.

I have a Palmer that is extremely loud with a 12 strand padded loop chad weaver string and is quiet with an 18 strand FF string from 3 Rivers. I do think strand count can make a big difference in the noise department and every bow seems to have it's own personality so I would try a couple different string options if possible to see which works best for your set-up.

Strand count can make a difference on some bows.  I've noticed a big difference witn one material--8125--on my personal bow.  With 18 strands, it's very noisy.  With 14 strands, it was super quiet--go figure.

Some bows just "like" some strings, or "dislike" some (my bow is quiet with just about anything other than 18 strands of 8125).

How the string is made, brace height, nock fit, release, arrow weight, arrow spine (changing strings may require you to change arrow spine), type material, number of strands, etc. etc. etc. can all have an effect.

Chad