I didn't know where else to post this. When someone has "captain call" exhaust that can be switched at the helm. Do they have both thru hull and thru drive exhaust? Or is there some other "y" pipe that has a " baffler" in it?? Thanks. Somewhat naive.

Silent Choice and Captain's Call are two different types of switchable exhausts. Default is through hull, and with it turned "on", it's through the prop.
Be aware, that "switchable exhaust" is technically illegal in many states. It is in Virginia, as it's derived from automobile laws that don't allow such. It is a ticket-able offense. It's absolutely stupid to be illegal, but again, it is in some states.

Now, when it comes to the through-hull portion of the exhaust, other than water (which does qualify as a baffle) as well as internal flappers (which are almost always present), there usually is NOT a muffler on the transom. SOME boats may have a muffler on the transom, but again, it's not typical. You could always install a muffled tips, or add these to the inside of your exhaust tips if you are concerned about noise and/or having a muffler where required.

I have a set of these which take the bark off the exhaust when needed:
http://teaguecustommarine.com/em0011...r-inserts.html

Yes. There is an electric or air operated diverter.

My 4" exhaust is through the hull above water or through the prop. Air is used for either or. Love the sound of the straight exhaust but it's nice to run quiet around the public docks and such. Oh it makes my wife happy to. Huge power diff. between the two. 502mpi with Gil exhaust

And then there is this option as well, which is what my boat has. Although this system does not quiet the boat down that much. No Y pipe required.

http://teaguecustommarine.com/em0011...er-system.html