Post your Exhaust db using phone & free app
Mar 17, 2011, 10:51 AM
#46
^haha, that sthe whole point 20 vs. 42..... quiet room vs quiet room....
i know that in my office, ~5:40am, nobody in-making noise, talking & such, the omega sound measuring device was reading 39 while the phone app was reading 40!
This phone app isnt an acid test or replacement for proper devices.
btw, what cams are you running?
i know that in my office, ~5:40am, nobody in-making noise, talking & such, the omega sound measuring device was reading 39 while the phone app was reading 40!
This phone app isnt an acid test or replacement for proper devices.
btw, what cams are you running?
BTW, which app are you using?
What is the lowest you have ever measured, anywhere??
Tried the car again too. Got 74/75 idle (odd it got louder fully warmed up) and 89 @ 2900 RPM (use a long screwdriver against the seat for those that don't have another person around). I also tried flipping the phone around in all different directions, had pretty much no affect.
I'm on stock cams, 9 turbo, megan O2, ported stock mani and turbine housing.
Mar 17, 2011, 12:15 PM
#48
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The chart that came with the phone app claims very quiet room @ 20, while it was reading 42. I just don't think it is going to be a good comparison tool from one person to another. May be good enough for before and after, but only if it is linear in it's error (again, between different phones/apps). Have read certain reviews of people who downloaded different sound level apps and them being off by 20db between them. So which app is right?
From what I have read, most consumer-level db meters are only advertised as accurate for a certain range, say 30db - 120db, etc. I would imagine a phone would have less range than that.
Mar 20, 2011, 07:45 AM
#50
So i recently got into a fender bender & I had a jdm rear bumper installed. the bumper hit my old 7" x 18" muffler, so i swapped that out for the dynomax vt muffler.....only becuase i had to do something quick & I already had it.
***Outside***
94 @ 1200 rpm
xxx @ 3000 rpm
...WTF?! the phone read higher @ idle, but the note is completely different....nowhere as "basey" or "boomy". i will modify the flapper so it doesnt flap so much...
Mar 20, 2011, 10:20 AM
#52
can you take a picture of your exhaust, especially under the cat to see where the mufflers / resonators sit.
So i recently got into a fender bender & I had a jdm rear bumper installed. the bumper hit my old 7" x 18" muffler, so i swapped that out for the dynomax vt muffler.....only becuase i had to do something quick & I already had it.
***Outside***
94 @ 1200 rpm
xxx @ 3000 rpm
...WTF?! the phone read higher @ idle, but the note is completely different....nowhere as "basey" or "boomy". i will modify the flapper so it doesnt flap so much...
So i recently got into a fender bender & I had a jdm rear bumper installed. the bumper hit my old 7" x 18" muffler, so i swapped that out for the dynomax vt muffler.....only becuase i had to do something quick & I already had it.
***Outside***
94 @ 1200 rpm
xxx @ 3000 rpm
...WTF?! the phone read higher @ idle, but the note is completely different....nowhere as "basey" or "boomy". i will modify the flapper so it doesnt flap so much...
Mar 20, 2011, 01:34 PM
#53
yes, it flapped @ idle in dynomax factory form....
quite honestly, that muffler sucks if you have big cams....for me, it actually sounds worse in the car @ 3200 rpm.....
initially @ idle, the car sounded like it had a really bad exhaust leak
so I modified the flapper by eliminating the smaller portion of the flapper, relative to the flapper shaft..... i will get #'s & pics showing the mod later on today.
quite honestly, that muffler sucks if you have big cams....for me, it actually sounds worse in the car @ 3200 rpm.....
initially @ idle, the car sounded like it had a really bad exhaust leak
so I modified the flapper by eliminating the smaller portion of the flapper, relative to the flapper shaft..... i will get #'s & pics showing the mod later on today.
Mar 20, 2011, 03:54 PM
#54
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it truly sucks that some of you live in states that care about this type of nonsense or haven't found legal loopholes around the laws as I have. Yes, some of you care about this out of personal preference and the desire for a "quiet" setup, but the rest of you worrying about this due to laws and inspection requirements, etc., I feel for you. Good luck with this little experiment Aby. 
Mar 21, 2011, 04:10 AM
#55
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I too had issues with the dynomax setup. It didn't like my 2.3 stroker with cams 
. That is why I went with the boost acutated cutout and stock catback.
I did get the rattling under control. I adjusted the wastegate arm that actuates the valve. The rattle is just about gone.
. That is why I went with the boost acutated cutout and stock catback.I did get the rattling under control. I adjusted the wastegate arm that actuates the valve. The rattle is just about gone.
Mar 24, 2011, 05:03 PM
#57
Originally Posted by Aby@MIL.SPEC 
can you take a picture of your exhaust, especially under the cat to see where the mufflers / resonators sit.
These are the best pictures I could take at this time. If you need pictures from directly underneath I can do that but I will need some time to do it. The first 2 pictures are the 7" round muffler that sits in the stock cat location or test pipe spot. The 2 last pictures are the pics of my 12" long resonator.
can you take a picture of your exhaust, especially under the cat to see where the mufflers / resonators sit.
These are the best pictures I could take at this time. If you need pictures from directly underneath I can do that but I will need some time to do it. The first 2 pictures are the 7" round muffler that sits in the stock cat location or test pipe spot. The 2 last pictures are the pics of my 12" long resonator.
Last edited by wizzo 8; Mar 24, 2011 at 05:06 PM.
Mar 27, 2011, 10:13 AM
#58
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I was bored today and remembered this thread so I just checked out my AMS TBE with HFC for fun. Held approximately 20" away and measurements were made with the Android Smart Sound app (so I doubt this could be considered truly accurate). The car has stock cams.
Cold start idle was 93 db, spiked to 100 when the car turned on
3500 RPM was 100 db
I'm not so sure about the 100 db reading because it sounded pretty damn loud haha I figured it would be a bit higher than that.
Edit - did some research about the 100db reading and it looks like the app just doesn't go past that, not even the pro version
Cold start idle was 93 db, spiked to 100 when the car turned on
3500 RPM was 100 db
I'm not so sure about the 100 db reading because it sounded pretty damn loud haha I figured it would be a bit higher than that.
Edit - did some research about the 100db reading and it looks like the app just doesn't go past that, not even the pro version
Last edited by deadmeat; Mar 27, 2011 at 10:32 AM.
Mar 29, 2011, 09:37 AM
#59
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I used iPhone app and it only goes to 102 dB. I believe I hit that at idle with my Greddy Ti with Cosworth 272s. I revved and it didn't go any higher.
I wonder if I should switch to an RRE stealth with the stock exhaust tip. I do love the sound of the Greddy though.
I wonder if I should switch to an RRE stealth with the stock exhaust tip. I do love the sound of the Greddy though.
