I got a ticket few days ago for my exhaust.. I orderd a Greddy evo 2 and waiting for it. I know the evo 2 is ratted 94 decibles but I was curiouse to seee what my current one was ratted.. and It's @ 100 decibles exactly. Is there really that big a difference? I just don'twant to run into trouble again and the whole point of me getting this exhaust is for that reason..
Thanks. I can't seem to find a clip of this greddy evo 2 exhaust anywere?

Google decibles. You'llfind what you are looking for. 6Db is noticeable difference.

Every 3 decibels doubles the level, so yeah, 6 dB is quite a bit -- 4 times as loud.

100 db is 10 times the intensity of 90 db. Our hearing sensitivity is logarithmic, so it doesn't "sound" 10 times as intense.

So basically, it won't sound like a huge difference, but the 100db exhaust could cause hearing damage much more quickly.

from a random google search: http://www.mckinley.uiuc.edu/Handout...h/noiseeh.html

Ah, science. Unlike weight or length, sound is very difficult to quantify. You can only subjectivly listen to 2 sounds and say that one is twice as loud as another. How do you determine that one radio is "twice as loud" as another. Yes, it's measured in decibles, but "loudness" to the ear is hard to quantify.

when unabomber did a db test on my evo catback it came out 93db at idle and 103 at 3000rpms, it really is not that loud just low,

It makes the sound but the loudness is below your ability to hear it.

on a positive note when i pit stopped at the bar lastnight on the way home from work i parked right next to a cop ,he didnt say a thing so it must not be to outlandish

It's still louder than my catless Prodrive set up though!

how loud is your setup ron?

91 @ idle, 101 @ 3000RPM

what is the stock db on a wrx? just so i can get a snese of how loud the after market exausts are.

There is a science of psychophysics that measures relation between perceived and physical scales. You present two closely related in intensity sounds to a subject and measure when the differences are noticed by a subject. The results are usually pretty robust.

Only really noticeable if it is your tires. And if it is you have a big problem.

In England there was an attachment for all cars that would solve your problem though. It was a device that hooked up to your stereo and made the sounds of your car with whatever exhaust you wanted through your stereo. It also hooked up to the engine somehow. And let you listen to your stereo if you wanted through the racket anyway.

It also would allow your car to sound like a Ferrari or Lambo or whatever. And it only sounded like this on the inside, unless your windows were down or your stereo was too loud.

But you wouldn't get tickets.

something that I had liying around
http://www.mattrandolph.com/wrx/cat-...omparisons.htm

I think stock WRX is 87 db

A +6 dB increase is a doubling of sound pressure, which is different than sound power. As a general rule, +10 dB is perceived by many people as a doubling of loudness (assuming that similar frequencies are being compared - the sensitivity of the ear varies over frequency). So yes, it's a pretty big difference.

just to confuse the matter more, there's a difference between Intensity Level and Loudness. Loudness is a subjective quantity that differs from person to person. So, +10dB Loudness could affect one person more than the next, but, by Intensity Level (not to be mistaken by Sound Pressure Level), 6dB is, as has been mentioned, doubling of said sound pressure referenced at 20uPa.

w00t.