Loudest to Quietest Exhaust System list (FRZ/BRZ)

[venturaII]

Originally Posted by Icecreamtruk

Im talking about actually driving the car. Revving a car at iddle the TRD is loud compared to most but that volume doesnt change much when there is load on the system (as opposed to virtually anything out there). I assumed the sound level when actually driving was what mattered. Also, the sound level changes a lot if using catless headers vs stock headers. In my case, it was comparing catless headers on both sides.

Ahh - gotcha. Never been in a TRD car, just on the outside. I drove the Greddy car and it was almost undetectable inside.

[Submarinesonce]

ive got a tanabe concept G, was 92db with stock header/FP...jumped to 99-100 db with catless header/resonated FP

[inonly]

Originally Posted by ryoma

MXP Exhaust:

they measured it at 102 db at the loudest when revving it, compared to the stock 88 db. I currently have it on my car at at freeway speeds (80 MPH) it's quiet enough that I can barely hear it over road noise and wind noise. I can barely hear it at idle with my windows down as well. with my windows up, I can't hear it over the engine idle. It's an extremely deep sound with no rasp at all. I love it.

This is a relief since I just got the MXP SP installed lol.

[gpvecchi]

102 vs 88 is a lot...

[churchx]

10 dB is difference between perceivable volume of twice louder (and 20dB accordingly four times louder).
14 dB of 102 vs 88 .. i guess ~ 2.6x subjectively louder?
Scale of sound volume numbers sometimes seem subjectively misleading (i guess, probably due relatively small numbers, one is often used to associate in subconsciousness with eg. percents or amount of something material). Difference between 35 dB and 45 dB may seem bigger then between 110 and 120 dB due relative "number" difference, when in reality both are jumps of doubled subjective loudness vs quieter one.

[tomm.brz]

Originally Posted by churchx

10 dB is difference between perceivable volume of twice louder (and 20dB accordingly four times louder).
14 dB of 102 vs 88 .. i guess ~ 2.6x subjectively louder?
Scale of sound volume numbers sometimes seem subjectively misleading (i guess, probably due relatively small numbers, one is often used to associate in subconsciousness with eg. percents or amount of something material). Difference between 35 dB and 45 dB may seem bigger then between 110 and 120 dB due relative "number" difference, when in reality both are jumps of doubled subjective loudness vs quieter one.

When i was studying it, we were "supposing" that at higher sound pressure the eardrum would "compress" therefore the perception of a lower difference, but yes I think usually 10dB more is perceived as twice as loud
it's a delicate topic, there is more involved in it that would need to be involved as well, like a frequency analisys

[gpvecchi]

Anyway, 102 dB is not so quiet as there are JDM catbacks declared as 90-92 dB, as JASMA needs (sound level legal emission test).

[inonly]

Originally Posted by gpvecchi

Anyway, 102 dB is not so quiet as there are JDM catbacks declared as 90-92 dB, as JASMA needs (sound level legal emission test).

92dB as their loudest? Please list those catbacks if aftermarket.

[gpvecchi]

Fujitsubo, Blitz, Tom's and Kakimoto seem to be the quietest.

[GrabTheWheel]

This is easy. The quietest is the stock muffler and the loudest is a cutout before the muffler. I highly recommend this setup, best of both worlds sound wise and you get little to no performance gain from a catback.