It is legal to use a silencer for hunting in TN, so as long as the silencer is legally owned then it's no problem. As stated, silencers on pellet rifles, or any non firearm are legal, but, since a silencer is a regulated item, it has to be nearly impossible to use on a firearm to stay legal. I just picked up a Benjamin Titan .22 pellet rifle with a silencer from a member here, it is much quieter than the springer it replaced, which means I can reduce the amount of squirrels around here without bothering the neighbors.