Ok here's the question. I just bought a new super kodiak grayling green. So now I have two. While shooting my new super kodiak I keep noticing how noisy it was, so I adjusted the brace height and knock point a 100 different ways. The bow shoots great. So I went and got my old super kodiak (2003 model) and tried it to compare the noise difference. They both have beaver fur silencers. The old super kodiak is so much more quiet. So I decided to switch strings. Now my new sk shoots as quiet as my old one. They both have Flemish twist strings the old sk I had made at about two years ago. The new sk string is factory. What will make one string louder than the other?

The string material used.  The old string is likely B50 dacron, the new string is likely FastFlight.

More twists?

They are both suppose to be fast flight. I did notice that the string on my older sk is smaller in diameter.

If they are both FF, then maybe it's the number of strands.  Fewer strands would in theory allow the string to stretch a little more on release.  Are the strings flemish or endless loop?

Number of strands, silencer placement, nock fit, type of material (there's lot of "FF" materials), tuning, arrow spine, arrow weight, etc. etc. etc. can all make a difference in noise.

Slivrslingr, they are both Flemish twist.