I play a 20" bass drum and have a 5" hole at the 3 o'clock position.
You'll forgive me, but I'm really proud of this groove - this is what it sounded like on one of my last recordings, and it's a great sound. I wasn't beating it up, I was literally dancing on the pedal and love this bass drum sound.
The batter head is a Remo PS3 and my mic is a Shure SM58 sticking just inside the hole. There is a small folded-up wool army blanket just on the bottom of the shell barely touching both heads. When I play out live in an un-mic'd situation, I put a full front head on with no muffling.