So the Coupe is no longer covered under the factory maintenance plan, so I found an independent shop to do the 6 year service. When I got it back, the exhaust note was completely different, and far quieter under all conditions. Turns out that my new mechanic discovered that one of the vacuum lines to the exhaust was disconnected; he assumed it worked its way out on its own and put it back.

I've owned the car for the past three years and had not only gotten used to, but derived enormous pleasure from the epic noise. Turns out that wasn't how it came from the factory, but due to having one of the pipes completely open all the time.

I was shocked at how bad it sounded with both lines connected that I was actually thinking that there was something wrong with the switchable exhaust, suspecting that it wasn't opening up all the way under any conditions. I don't have direct experience with a known good F-Type so I'm not sure, but my mechanic doesn't think so. He noted that with it reconnected, it was much quieter under normal conditions but hit full volume at high load.

So, both lines connected, to my ears sounds very thin and tinny, and never got particularly loud in the cabin. It had a BMW like nature to it, but far less appealing.
One line disconnected, exhaust sounds deep and throaty but with a very pleasant wail WOT.

Needless to say I had him disconnect and plug the line, to return it to its previous sound. So V6 owners, maybe try disconnecting one of your vacuum lines before replacing the exhaust with an aftermarket part..?

 

You could have just left it connected and pulled fuse 43 for the same effect, except you'd get both of them open all the time instead of just one.

 

Indeed. We did a few tests: both connected, one connected, and none connected, and having both pipes open all the time was... a bit too much for me.

 

Interesting. My R is quite a lot louder than every other F Type I've come across, maybe it's something similar.

 

Have you come across F-Types of a similar age to yours? Later models have got progressively quieter.

 

I’ve had one valve stick open occasionally. It’s a pretty good compromise; I don’t open both valves (via F43 relay) in my neighborhood as it doesn’t take much for the exhaust to erupt when pulling away from a stop sign.