Exhaust - Sound Meter Thread - please post your examples

[cheekychimp]

Well I figured you could be right about the phone (it's a Korean model that's not in the supported list). So I switched to my Galaxy S3 but I still get a rock solid 60dB in the office with no-one talking and only the sound of the central A/C. Admittedly the fan is loud compared to a lot of A/C systems. It flits between the 50dB "Quiet office, Rainfall" and 60dB "Normal Conversation at 3ft." index and it does jump to 70dB when I put a ringing cell phone next to it, so it may not be far off.

But without meaning to put a damper on this, I think the calibration of the phones/meter app and the difference in the phones used could potentially skew the data enough to detract from what you are attempting to do.

I saw in a post above that you queried a difference of 10dB from a setup similar to your own but you also said replying to my post that you get 30dB reading in a quiet room. I guess "quiet" is a pretty vague term but looking at the index on the app itself 50dB is the average reading for a quiet office and I get a rock solid 51-52dB out near the lobby away from the central A/C and fan noise.

I'll give this a try on my setup and see how it compares with yours.

I'll also put it next to the Suzuki DRZ400 with the MRD exhaust. /ubbthreads/images/graemlins/rofl.gif I'm sure it will clear 110dB. We opened it up in the shop the other day and the exhaust bounced off the wall behind it and knocked parts of the shelf in front of it /ubbthreads/images/graemlins/rofl.gif


Quoting tsitalon1:
@Cheeky, That's strange, I only get 30db or so in a quiet room.

You must have a vented wastegate on that AC unit /ubbthreads/images/graemlins/ooo.gif

Maybe your phone's mic is more sensitive??? Have another phone to test with?

 

[tsitalon1]

Yeah, I know the variables are many and the accuracy might be as good as we hope, but I'm hoping it's better than listening to youtube video's with camera's recording at ground levels.

How about in your home by yourself with nothing making noise...except the AC? Should be closer to 30db.

 

[EHmotorsports]

I had to calibrate mine down to 30 db in a home with nothing on or running. It was 40db before hand.

 

[cheekychimp]

You're right! It is, so it's probably not far off.

In any event using the same app to measure any changes in a setup should still give useful results. Even if the two readings are not 100% accurate themselves, the difference between them should be an accurate indication of how much the sound has increased or decreased.

Quoting tsitalon1:
Yeah, I know the variables are many and the accuracy might be as good as we hope, but I'm hoping it's better than listening to youtube video's with camera's recording at ground levels.

How about in your home by yourself with nothing making noise...except the AC? Should be closer to 30db.

 

[cheekychimp]

Current exhaust config:
EVOIII Manifold
Big 16g turbo
EVO III O2 housing
Unknown 2.5" downpipe
JDM "Jasma" exhaust
JDM muffler (I'll try to get more details but it's pouring with rain right now!)

Sound levels with windows closed all sounds (Radio,blower, etc) off.

Car off in quiet driveway = 30db
Idling = 61db
Cruising at 70mph = 77db
3rd gear WOT = 79db

 

[tsitalon1]

I was hoping this thread wouldn't die!

Great, these numbers line up close to mine, so we are getting some consistency, unless of course your exhaust is loud as hell in real life /ubbthreads/images/graemlins/smile.gif

Mine is fairly quiet, but I will be looking to quiet her down even more, maybe with a resonator and switching to a vibrant muffler.

 

[matt92vr4]

I just increased me boost from 15 to 20 last night. I'll get some new numbers today. Honestly I think if you just swap in the vibrant muffler you will be very happy. My car is very quiet.

 

[cheekychimp]

I'm actually very interested to try that muffler you posted as well. Not so much on this car as I think it is quiet enough but has a really nice note to I that makes me want to leave the windows down the whole time. The other car however is loud as hell and desperately needs some attention. I love the fact that it is black as well because I will be aiming to have nothing other than brake disks and lights that are not black on that car.