FWIW, the Crossflow in my Mallock sounds quite different from the Crossflow in my Caterham.
The Caterham is more mellow, and pitched lower. More Baritone. The Mallock is brighter, harsher, and higher pitched. Closer to a Tenor.
I’ve always assumed that much of it is from the higher compression ratio in the Mallock (either 12.5 or 13 to 1- can’t remember off the top of my head) and the cam profile. It also has straight pipes, no muffler.
I think the mic will be in front of the exhaust, which is likely rear exit just based on me hearing it (lack of wind noise is the giveaway). The mic is unable to cope with the input - that may sound good to you but the sound is breaking up. That tells me it is relying on the action camera to power the mic - no separate power source. A good powered mic will improve the quality of sound from what you hear.
Mike
2021 Caterham CSR "CatKong"
2010 Caterham CSR with Cosworth 2.3 Duratec
2018 Caterham 420R with 2L Duratec 210hp at Donington UK
1972 Lamborghini Espada GT
1975 BMW CSL Group 4 (restoration finished - track set up time)
1977 Holden Torana "A9X" (awaiting restoration)
1985 Holden Commodore SS Group A (suspension restoration)
1985 Holden Commodore Group A (suspension set up)
1982 Ferrari 400i (radiator replacement)
1965 Ford Mustang Fastback "Holman Moody"
1992 Ford Escort RS Cosworth WRC (dyno time)
1990 Range Rover 2 door Classic