the differences in sound are given by a combination of factors, here are some:
1) exhaust note: a T-6 with short exhaust will sound a tad louder and crispier than and a Harvard with longer exhaust.
Same goes for similar engines installed of different machines: flame dampeners and exhaust design all contribute to the different sound.
2) propellers: a two bladed constant speed propeller will sound very loud when its wingtips go supersonic, whilst a 3 or 4 bladed prop will be more efficient and less prone to that. That's why a T-6 is louder than a Mustang.
3) aerodynamic features: the "Mustang howl" that we all know is caused by the angle and shape of the gun ports, which work as a whistle at certain speeds and angles. Same goes for the design of other aerodynamical features of the plane.
4) mechanical and structural features: superchargers, turbochargers and other similar features all contribute to the sound. The whizzing noise in the Bf109 is caused by the supercharger impeller fan.
Airframe resonance is surely another thing to keep into account: the shape and construction technique might give the plane a different resonance, but again this is something for fine listeners.
5) last but not least is the kind of engine! The combination of RPM, number of cylinders and setup of the crankcase all contribute to the distinct rhythm of an engine.
So no, an ASh82 won't sound exactly like a BMW801 because there's different exhaust curves, different engine mounts, different cowls, different idles. It's the same configuration, but it's no cigar.
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