So with all the talk of exhaust "my exhaust is quiet vs. that exhaust is loud", all while describing the same exhaust, lets put a little science to this = decibel readings.

Im not about to buy a proper sound measuring spectrum device, so i decided to load up a free app on my cell phone: smart sound by android boy onto my android 2.

California law calls for a 95db limit measured 20" away between 3k-5k revs in neutral.... I only performed a idle & 3k rev.

I am thinking about just simply listing your eng / exh mods.

I also performed an idle check as well, both inside the cabin, phone near ear level between the 2 front seats & windows all the way up = closed.

Here are my results....

I took the measurement 20" straight - away from the exhaust.

2.3L, s2 cams, fp-black, e85, 3" o2, 3"dp, 3"exhaust, no cat, 2 x 18" long 4" o.d. resonators, 7"x18" round muffler

----------------------outside / inside

idle @1200----------92 / 59
~3200 rpm--------100 / 72

fck my exhaust is loud! The scary thing, i hear evo's all the time with much louder exhaust!!

Post your results!

 

my mods are below, at 3500 rpm 20 feet away on hks TI catback 90db. this exhaust is quiet

 

i want to know, what exhaust is the loudest

 

I might have to do that later today since mine has different pitch variables when its cold start to warmed up and idle and going hard.

 

my exhaust gets quieter the further away i go to....you cant hear a thing 5 miles away

I did this with a warmed up exhaust too....not the 5 mile test

seriously though....Please stay on topic

only post results taken from 20" away from exhaust tip

 

loudest exhaust: tanabe medalion concept g

 

As I mentioned in a previous thread, there are in essence two kinds of dB readings - A-weighted and C-weighted. The reading mandated by the state is A-weighted. The problem with an A-weighted reading is that it doesn't account for any low frequencies, so in order to get a number that's relevant to one's perception of loudness the readings have to be C-weighted. This is a crucial point. I understand that car guys aren't audio guys, and that something like this many not be immediately apparent. Fair enough. This being said, if you want to make this thread relevant, this is something that must be noted.

Too, as Aby mentioned, the position of the meter cannot vary; its angle and distance to the source has to remain a constant.

 

Inside ear level 55db. Havent done it at the rear of the car. This is also with windows open.
Tsunami exhaust, megan test pipe, HKS 272's

 

great idea. this thread could be the most useful one, but you are going to need a mod to constantly clean out the replys that dont fit the criteria. as soon as i get my evo out of storage ill do mine. its bone stock down to the air filter so its a good stock baseline.

 

I located a run of the mill sound measuring device from 1 of our labs, it's a Omega HHSL1

I will post the findings of this device in C & A + my phone during the same time for gauging the accuracy of using a phone vs a purpose built device.

who's going to be the 2nd full sound analysis poster?!?!?

 

how do i get this app?

 

Its not just about how loud/quiet an exhaust is, its also the tone it has that can be annoying. Example the deeper and the more bass it has, the more its going to have that annoying drone feel. I've concluded the higher the tone the less annoying the sound is compared to the deep bass note.

And in regards to my setup. A fellow member I met a short while ago was standing 15 feet away by his car and asked me to turn my car on so he can hear my exhaust. I replied to him, its already on!!! We were in a mall parking lot not far from the street traffic, but not like a highway and construction zone lol.

Sorry no decibel readings.

I'll try to make another video on the iphone 3gs.

 

wow that exhaust system cost 900 bucks, expensive as $hit

 

just go to your app store & search decibel meter.

I just chose the free 1.

i might load up different apps to see which app gets me closest to a proper measuring device.

 

I'm going to do this when I start my car up next Aby. My Trust Ti-R is effin loud. I'll report back in a few days!