83 dB too loud for a daily drivers exhaust?
 

I'm almost set on getting the milltek Primary non resonated exhaust. I like the sound but it's hard to tell how loud it is online. I've read it's about 83 dB, is this too loud for a daily driver? I need some opinions.

85d is max exposure in an industrial setting so it depends if its 83d all the time or only at full throttle.

Legal exhaust noise levels for most areas run between 85 and 90db so you should be OK at 83.
But... yours could be different so you may want to check it out.
And... keep in mind the closer you get to the limits the more likely you are to get checked up on even though you are compliant.

Time weighted to 8 hours exposure at DBA slow response. (Finally a subject I an actually an "expert" in!)

Another website I saw rated it at 70 dB but the distance was at 10 feet long. Ideally db should be measured at 3 feet correct?

Then you know 83db at cruising speed will be extremely freaking loud!

Depends entirely on your sensitivity to NVH (or local laws). I've daily driven motorcycles that were about 103dB @ 3 feet. And My FR-S peaks over 102Db @ 70 feet and full throttle.

Yep! But greatly reduced inside the car and the industrial limit is 110db for up to 15 minutes. So as long as nobody is cruising beside you in an open convertible for 15.01 minutes all is good.


Our legal limit for exhaust here is 87db (which seems like a pretty arbitrary number really).


There is also a set standard on how the "pass by" exhaust volume is measure that I just posted on another thread the other day but be damned if I can remember which thread right now!


Now I am curious and am gonna throw the meter on my TRD exhaust.

Anything over 90 db (whether cruise or WOT) gets annoying to me now (unless at a track). Below 85 db is not bad at all for a daily driver, but it may seem worse if there is excessive drone or resonance.

Remember decibel ratings are logarethmic so even seemingly small changes from say 87-92 db are significant when it comes to perceived loudness *to me.

I have a 40 page training PPT on the subject if anybody is really bored!


Wolf nailed it anyway with the word "perceived" since what I think is too loud, the next guy may think isn't even starting to get loud.


I don't think my TRD is "loud" but my wife can find me across a large busy parking lot just by sound!!!

With loud, drony exhausts I've found that its all about gear selection...my exhaust drones like a bitch at 2000rpm but is quiet as a mouse at 3000 then absolutely roars at 4000 and above...so you basically have to compromise fuel economy to keep the noise out of the cabin with the louder pipes

And mine peaks at 120db and my hearing is fine...as long as you speak very loudly...:D

It's the other way around. Going from 87 to 92 more than doubles the amplitude of the sound, but it doesn't sound like it to our ears. We only perceive a change of five equal steps up the scale. To actually perceive a doubling of loudness, you have to double the decibels, say from 50 to 100 db.

I can easily perceive a 5 db increase...I used to live near train tracks and I could tell when those bastards switched to the 110 db max horns from other horns that were "only" 96-100 or 100-105 db (I used a decibel meter to verify it for myself)...and yes I know that going from 105 to 110 db is even more significant than 87 to 92 db...

I'm pretty sure that a vocal conversation is somewhere around 70-75 dB.. So 85 really isn't that loud. People routinely listen to sounds in excess of 100 dB without being bothered... You just don't do it all the time or it gets annoying. A drum set is typically rated at 120 dB and that's loud as shit. The loudest possible sound that can exist in our atmosphere is 212 dB because after that it's a shock wave (ie explosion).

Also that logarithmic function is related to the energy in the waveform that a listening device perceives. If I recall correctly, each decibel is supposed to be an individually distinguishable loudness to our ear, and the energy required to go up 1 decibel is twice that of the one below that. Hearing damage is a function of exposure loudness and time so look it up.

I hope so. If you can't, there might be something wrong with your hearing.

My point was that a 5 db increase from 87 to 92 doesn't sound like the sound more than doubled. It's five linear steps up the scale that humans perceive as a 5%-6% increase in sound level.

Almost. Power doubles roughly every 3 db. So from 0 db to 3 db doubles the power. 0 db to 6 db quadruples it. Etc.

Guess that's why I told you yours was the best sounding twin at a PIR track day.

I should let you hear the exhaust that doesn't pass sound at PIR some time, pretty amazing how much a single 5" canister muffler reduces the volume.

Agreed! :D

Don't be fooled by decibels.

Moving twice the distance from the original measurement reduces DB by 6.

If the original measurement was taken at 6 inches from the pipe, and you get 83 DB then you get:

1 ft = 77 DB
2 ft = 71 DB
4 ft = 65 DB
8 ft = 59 DB

Of course, if that was taken at 4ft then you get a relatively good assessment. Still, 8ft goes to 77, 16ft goes to 71

dB are logarithmic, so this can be a very deceiving stat to look for. I would at all costs avoid it when determining what exhaust to use, purely because there is no standard by which everyone measures the exhaust from in terms of distance.

Although I totally agree with the rest of your statement the last line is not correct!
The measurement of exhaust sound levels in covered under the SAE Standard J986. It is very clear how and where the measurements are supposed to be taken.


Now, having said that just how many places know/do this is a totally different matter!


http://standards.sae.org/j986_201311/


http://media.caranddriver.com/images...s-original.jpg

Fair enough. But yeah, impossible to know if they actually do it or not. That's why these results can be so misleading! it is a shame it isn't easier to just listen to all your choices, in person.

Lol my bike is 105 dB... Guess that's why my hearing is $hit

I know perfectly well what happened to my hearing!

Of course things like this will be entirely subjective but fwiw - I have never had an aftermarket exhaust before, I am someone with sensitive hearing, and (in general) I hate loud noises.

I purchased a Tomei type 60S (which I believe is rated at 91 - 93db with an all-stock set up except for the catback), and I've had it installed for a few months now - and I love it. I think it is just loud enough that it makes it fun, and exciting to open up the throttle, and it compliments the car well in terms of getting a good amount of feedback when you're driving.

I was really worried that it would be too loud, and admittedly the cold starts are, but I love everything about it. It's not going to be obnoxious, or piss anyone off as long as you're not trying to drive like an ass, and even then it probably isn't going to be louder than the average motorcyclist accelerating.

I'm also not sure if this was just from getting used to the exhaust, or if this is the case with all exhausts or not - but I genuinely felt like my exhaust quieted down a bit after 3 - 4 weeks of driving after getting it installed.

I think you'll be more than alright going with a 83db rated exhaust - if the concern is your comfort while driving, you'll have the option of doing a sound tube delete which would probably quiet down the in-cabin noise a bit, but really - I think you'll be quite happy with a new exhaust, and you won't even notice any issue(s) with the sound (or maybe you'll even want it to be a bit louder) after a few weeks of DDing it.

GL :thumbsup:

The proper way test if an exhaust is too loud is

to floor it up and down your street in 1st gear and only use engine breaking

if no one comes out bitching then your good to go

if someone comes out bitching tell them to FUCK OFF!!!

83dB is pretty quiet, it also depends on how it is measured, at what angle and distance from the tip, what speed/RPM range etc. IIRC my dads stock Z4M was measured at 96dB at WOT from a distance of 10 feet parallel to the car, his Caterham is significantly louder than the Z4M and requires ear protection when driving. I am willing to bet the Milltek is much quieter than both those cars in real world circumstances when driving.