maybe there is a simpler explanation. The wind noise gets pretty loud,
louder than the exhaust and you auditory system effectively scales down
the RMS of the total sound. the exhaust then seems quieter.
I don't know enough about the physiology of the ear, but I don't think the
total
noise *seems* to increase all that much when it in fact must!
Mike
-----Original Message-----
From: Les Myer <LesMyer@geocities.com>
To: spridgets@autox.team.net <spridgets@autox.team.net>
Date: Tuesday, December 15, 1998 7:06 PM
Subject: Re: Mine scares me, it likes the speed
>At 04:06 PM 12/15/98 -0800, you wrote:
>>"Did you know that 1275s get much quieter above 6000 rpm
>>(at least from inside the car)?"
>>
>>Maybe you broke the sound barrier! Did you hear a loud boom?
>>
>>Larry
>
>I kinda doubt it, but I did break the speed limit!
>
>Actually, getting quieter at a higher exhaust note frequency sort of makes
>sense from my experience. Remeber the H-pipes connecting dual exhaust
>systems in 60's Fords. I read once that the H-pipe allows both sides to
>experience a higher frequency of exhaust puslses, effectively quieting the
>entire exhaust system (or something like that). I did this to a V-8 with
>headers (full length exhaust system) and believe me, it does work! I
>suspect the 1275 got up in a frequency that somehow was not apparently not
>so loud. Where's an engineer when you need one? Who on this list can
>explain these observations.
>
>Les Myer
>
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