There was a bit of discussion on another thread about this, but I think it may warrant its own discussion.

Most of us know that the Max has some kind of sound generator to make the engine sound better/more agressive inside the cabin under hard acceleration. But how is it implemented exactly? Is it piped from the manifold through the stereo/speakers, a natural sound given off by the manifold based on the manifold's shape, a resonator somewhere, or something else? And last of all, is it referenced or diagrammed in the service manuals somewhere?

I'm asking because 1) I'm the curious type, and 2) I'd like to eventually disable it if I upgrade my exhaust to one that actually produces enough sound to hear. No sense in having extra, artificial noise in that case.

Thanks everyone!

-John

 

I didnt know the Max had this but the new Mustang has a tube after the intake filter which runs to the cabin. It has a diaphragm in it so no air is passed but the sound is.

 

its called putting more load on the engine that's why its noisier. there is no sound generator. any engine makes more noise when you put more load on it.

 

Like previously Stated, The mustang does have a sound tube.

 

Shoey1 - Your response sounds reasonable,

BUT

Nissan told us very clearly at intro last March that early test versions of the '09 Maxima were too quiet in the cabin; very little sound, even while accelerating all out. Just did not sound sporty. They specifically told us they 'fixed' the problem by transmitting sound from the manifold area into the cabin. Not much, but enough so we could hear the power of the engine when accelerating.

They did not get into the exact nuts and bolts, but did mention the word 'amplify'. So this may have been done slightly differently than the Mustang's tube/diaphragm. It would be interesting to know the exact details.

 

I remember them saying they did that as well. But never said how they did it. IDK why they would do that with a CVT tho. So you can hear the rpm hang at 6k??

 

So it wouldn't resemble the boring and quietness of a Lexus? I respect Nissan for fixing this issue as it comes in handy for me on the highway to know if i'm accelerating or not without having to look down at the speedometer every few seconds.

I loved this type of sound on my M35x because it keeps my eyes on the road and not on the speedometer, and i'm glad Nissan noticed this and decided to fix it before final production.

If anyone knows how Nissan implemented this function, please share.

 

Amplify = remove some sound deadening material on fire wall.

 

Thanks for the replies everyone. Most reviews allude to this generator. This is the most detail I can find... from http://www.tirekick.com/TK07/09NissanMaxima.htm:

"Quietness is ordinarily a virtue in family-carrying sedans, but the sporty nature of the Maxima demands a bit of sound. "For enthusiast drivers," Perry explained,"you want to give some feedback." Engineers actually had to add a "sound generator" to produce noticeable tones while accelerating. Those specially-created sounds actually emanate from the engine's intake manifold, not the exhaust system."

So while it's totally possible that part of the design included less sound deadening material, it also sounds like there's something else too, specifically relating to the intake manifold. Or else it's just marketing spin...

 

Shoey1 was clearly cracking a joke (and a right funny one, at that). He knows Nissan would not say they installed a 'sound generator' to modulate tones derived from the manifold if all they did was remove some sound-deadening material. There would be folks who knew exactly what Nissan did, and an untruth of this type would be terrible for public relations.