Decibel readings of 2017 BRZ vs other cars.
 

Well. I bought a 7/8" set of nylon plugs from Lowe's hardware and went test driving. (the plugs went right into the sound tube hole, I did not bother to test it without it plugged.)

I used a sound technician Iphone app on my iphone6. It is not calibrated, but it is very good with relative sound, and samples several times a second, posting max sustained decibel ratings. Nifty thing.

1. 2017 BRZ limited (automatic is all they had to test):

64-67 MPH on New Jersey roads: 69.0-72.0 dB(a) Mostly 70.5dB(a)
Subjective noise: Very high range slight transmission of sound into the car from other cars and environment. Lows range quiet, mid-talking=quiet, mid-upper was fine too, a slight gentle hiss range environmental sound came in. Also, on normal acceleration winding to 4400 about for a sec= 73-74 dBa. Parked chilling out, easy easy to have a conversation in.

2. 2006 Mini Cooper S - 15"rims, 205/15"/60 falken AS tires, mid-low noise range, definitely better than "any low rolling resistance" tires I have tested on new cars:

64-67 mph on almost the same exact route: 69.0 - 71.5 dBa, mostly 69.5.
Subjective: less midrange negation of sound, less lower negation as well on acceleration. Speaking voice interference is similar to BRZ, which means very little at all.

3. Mazda 3 2017 GT manual. 18" AS wheels: similar roads (very similar, some of same route) Same speed range:

70.5-73.5 dB(a). Most of the time, 72-73. Midrange noise = considerable. WOuld have to raise voice a bit in an important conversation with a young, non-deaf passenger. Kind of terrible noise. tires suck? 18" wheels = marketing gimmick = suck? Probably. I would sell the 18's and get 17's and higher profile tires rated for good noise.

4. 2017 WRX manual: Smoother roads. Sustained speeds of 50mph. Sustained 73-74dBa. Acceleration was like 75's. Ability to block outside noise was quite good. Noise quality was not bad, conversation range was fair to good, adequate I would say.

5. Subaru 2017 Legacy 3.6R limited... Get ready for this: Smooth highway was 59 dBa. Rough road was fluctuating low 60's dB(a). You can have a very quiet conversation at 70mph on a decent NY highway and hear people sighing. Holy Crap :eyebulge: Parked it is not far off from driving in dBa ratings. the only spikes in the sound levels was clearing throat and quiet phrases spoken.

6. VW 2071 GTI SE: Same road, different part of it, only up to 61 sustained (it had a limit of like 45). 68 dBa sustained. Outside sound transmitting into cabin: incredibly low, blocks roadways parked next to one during rush hour. Can take a pleasant nap easily in one parked.

Timex watch test: Can both passenger and driver hear the watch ticking? It has a big and pleasant tick to it, quite loud if room is quiet.

Cars passed:
BRZ 2017 with plugged hole (i always love a plugged hole :wub:)
Legacy 3.6R
VW GTI SE 2017

Failed:
WRX 2017
Mazda3 2017 GT
Mini Cooper S

Most tolerable interiors by picky non car enthusiast:
Legacy 3.6R 2017
GTI SE 2017
BRZ 2017
Mini Cooper S 2006 as I have it set up. the original set up was not tolerable in any way conceivable.

People thought was dumb: WRX and the Mazda3

So, whatever is said about road noise, I cannot imagine is due to the design of the 2017 BRZ. It may be due to tires + sound tube or because of an earlier model. The more rigid suspension maybe transmits less sound?

All i know is that I am picky about loud noises and the 2017 BRZ limited (at least tested in AT) I would recommend to cruise or solo car in. I am very impressed by it and wonder what is going on with the other people in the forum in terms of their experiences.

There is a discernible high high range transmission of sound from outside into cabin, but this is present in all of the less quiet cars, only difference is that they are bad on more of the audible range and you dont notice it.

I think the best test was the Timex watch tick test. that really was the only non subjective, no-needed to calibrate absolute test.

Great write up. It's good to see that the changes they made to the sound deadening is working well. I am pleased to hear this since I have a 17 on order. Hopefully the manual won't make a huge difference with the change in rpm.

Thank you

I did not know they changed sound deadening things. I am trying to piece together these bits of information to make sure i buy the proper car for myself

http://www.auto-decibel-db.com/

this shows the 2012 BRZ as having better or similar decibel ratings than many cars that are much heavier. It shows results at the lower end of my spectrum of readings.

Also note, the 2.5GT legacy is 59 decibels at highway speeds. This confirms my results. At some parts of the highway in the 3.6R i drove, it was like 55-57 dba for lengths. The car is near silent for a car.

what is really odd is the results for the mazda3 GT. IT has it at quieter than the BRZ. I really do not see how that is possible. Well, I did plug the sound tube, maybe that is why? The mazda3 GT in their results is very quiet. I am thinking this was conducted on high quality roads.