The exhaust on my old Range Rover split between the catastrophic converters and the first silencer, leaving it completely open.

The novelty of it sounding like the start of Jerry Was A Racecar Driver hadn't entirely worn off before I welded it up, I guess, but I'm not about to go around attracting attention to myself.

Not when I could see it making plate glass shop windows vibrate.

https://www.youtube.com/watch?v=KkE4-zsqYwo

catastrophic converter is such a hilarious autocorrect.