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      07-28-2013, 02:08 PM   #99
swamp2
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Drives: E92 M3
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Quote:
Originally Posted by Mangler View Post
I took a 1/3 octave snapshot of the highest rev point at the 3:06 point in the video. There are two peaks at 300 and 500hz but all the energy is around 1200hz and they are not harmonics. How are you deriving the 370hz for the calculations? When I am back to a PC ill post a screenshot. Don't know why we can't just upload pics from mobile. So stupid.
Automobile noise is very broadband on nature. Some sources are tonal but those. simply mix with the broadband ones. Sources include, engine, exhaust, wind and tire. It isn't necessarily that the combustion frequency always has the most power. As I posted earler the fundamental combustion frequency is often the second (lowest) peak in the spectral content. That being said I'm not sure what the first peak is in those cases.
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