What is the quietest suppressor for 6.5 Creedmore

What is the highest decibel reduction suppressor for 6.5 Creedmoor? I am thinking about getting one but am completely confused which one has the best performance.

I’m not hung up on it being an actual 6.5mm suppressor, .30 is fine, I’m just looking for the most objectively effective.

You worried about length? What’s the use of the rifle?
 
I gotta second that TBAC .338 Ultra.
Shot next to a guy running one in a 6.5 Creed at the last match and it was just ridiculously quiet.
Not cheap, but if you want quiet-est…..