I was kinda beating myself up for not doing this earlier on my Q50 which has sport exhausts and has the Bose ANC/ASC feature (Active Noise Cancellation, Active Sport Cabin). It made a huge difference in terms of reducing cabin drone and actually hearing what the exhaust truly sound like after 3 years of listening to fake noise garbage. The overall music audio was better too since the low-frequency was not being drowned out.
The principle is simple. There is a firmware with the pre-recorded engine and exhaust sounds loaded into the bose system for various RPM. When in ANC mode (comfort, etc) it uses the 2 mics in the cabin to essentially cancel the engine and exhaust sounds ...kind of how noise canceling headphone work. In the ASC mode (when in sport) it pumps fake amplified noises into the cabin when accelerating. The challenge is that if you change the mid-pipe or exhaust or modify the engine and the harmonics are off, then i's just pumping low frequency garbage into the cabin.
Since I don't have a later model GT-R, I had to get help from NickTO to obatin the ESM so I could share this, since it doesnt seem to have been discussed here prior or I just missed it.
1. Turn ignition ON
2. Turn audio system off
3. While holding "MENU" button turn volume knob 40 at least 40-clicks in any direction.
4. Select "Confirmation/Adjustment" mode
5. Scroll to the "ANC/ASC" setting and select it
6. You have to do a "Connection Diagnosis" first, before settings can be changed. It will show you the name of the firmware I talked about above. go back to ANC/ASC menu.
7. If you want to hear the annoying sound pumped in click on the "Active Test". It's so low frequency that my phone couldn't even record it.
8. Click on "Setting" and turn each one off. - ANC and ASC
I am not sure the GT-R will allow for each one to be turned off independently, the Q50 did. I noticed good results from ASC off. No more fake sound. The idea is that ANC cancels out normal road engine noise, but with different tires, tune etc, I actually ended up turning ANC off too and my overall music audio sounded better. I could also hear the engine rev.which I like.
9. Back out of the setting and the system will reboot, takes 1+ minute for whatever reason.
I'd be curious to hear about the results from GT-R owners people trying this out, even those with stock might actually find this better. I think this was introduced in US16 models onward? Getting rid of fake drone was the best.
Edited by d-pak, 15 May 2018 - 09:33 AM.