At about the 3:30 mark he gets down to business . It's actually a very good explanation of how the exhaust creates that music . The guy researched it for about 9 years believe it or not by doing interviews, building exhaust systems etc . Don't forget that technology is really proprietary closely guarded info . It's worth a watch even with the questionable intro . He is just making the point that the majority of YouTube videos relating to the subject are completely bogus .I clicked off at the first mention of "click bait"...