We put some new strings on an Xforce 7 at the shop and figured we would do some experimenting with the brass nocks. we started out at 280 and ended up at 289 by adding 6 total to the string. Im not sure if it made it any quieter or not b/c that bow is litterally whisper quiet. Its a freak of nature. It is for real one of the quietest bows ive ever heard.

Derek