Heard of it on posts, but no direction on how to remove or where it's located at exactly. Does it make a noticeable improvement?

 

the silencer ring is a little aluminum or ss jobber that sits right at the mouth of your turbo to provide a smooth entry way for the air coming in. It is held in place by a snap ring that is somewhat of a PITA to get a screwdriver under as its hard to see which end is slanted the correct way to get the tool under. even so it maybe a 30 min job. just take the intake hose off the front of the turbo and go to work. Be carful to stay off the impeller blades as they are coated with a powder that balances them out. it does make the turbo louder with no apparent neg or pos side effects. I took mine out within the first week or so I had my truck because I couldn't stand not having some sort of noise coming from under the hood of my diesel truck. Well worth the time just to get under the hood if nothing else. Note: if you don't have any other mods done to your truck it will not make the turbo that much louder. Hope this helped.
I'm gone to thanksgiving, Peace
Nick

 

After I removed my silencer ring I didn't notice much of a difference in sound until I removed the baffles from the intake tube.

FWIW, I did a search for "silencer ring" and came up with 500 posts. This topic has been covered extensively.