What's fake about exhaust noise?

Burn

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Inspired by the recurring rant from Jezza, and also recent posts in the awesome thread, I just have to ask, what is "fake" about exhaust noise?

So if you design an exhaust to give a certain sound, the "real" engine sound would be the engine without the exhaust, right?


but I just think that sounds wrong... Also it sounds worse in person, but you just can't capture that with most microphones because it's just too loud.

Engines are very loud, the more you hear of it, the more real it is. And also, no matter what kind of exhaust you fit, it's always the sound of the engine you can hear going through different pipes and silencers.

So in my mind, as long as you don't fit speakers to a car, the sound isn't fake.


What do you think?
 
all engine sounds are fake, even the cgt or 917 have their exhaust tuned to make it sound a certain way

but lately aston martin, mercedes, jaguar, mute the engine completely, and add a rumble to the exhaust because a supercar that makes no sound is dull...

that's fake! if you want sound, work with the engine note, but don't create a complete new one!
 
Actually, I think what he's talking about is the fact that several new cars have sound synthesizers that produce a fake engine note in the cockpit - mostly because the noiseproofing in those models is so good you either can't hear the engine note or it makes it sound terrible. The new M5 is one of the worst offenders - it actually uses the stereo system to generate fake engine noise inside the cabin from the speakers.
 
@bone: how would this "add rumble to the exhaust" work?


@spectre: So they really are using speakers? OMG
 
@bone: how would this "add rumble to the exhaust" work?


@spectre: So they really are using speakers? OMG

Burn: Some companies (including Jaguar now) are adding a resonator in the cockpit area so an artificially resonant exhaust noise is heard in the cabin. It's still real exhaust generating the noise and if you punched a hole in the resonator, you would get exhaust fumes escaping out of it. However, some companies like BMW just said the heck with it and went with speakers.

Did you miss the 'new M5' review in the last season of Top Gear? It was explicitly mentioned. If you give me a minute, I can go look it up and give you both the episode and the timehack where the commentary is.

- - - Updated - - -

It's 18x07, 1:41-2:23.

"When you're driving along, you can certainly hear it... but then you would, because they've fitted it with a system that pipes a synthesized version of the exhaust note through the stereo." - Richard Hammond

It's FAAAAAAAAAAAAAKE.


What's really funny is that reportedly the synthesizer can get desynched from the actual engine and if you roll down the windows you hear two different exhaust noises - the real one and the one piped into the speakers - sometimes radically different.

BMW - The Ultimate Faking Machine.
 
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Must have missed that, but I do have the episode here, so I can watch it some time...

I think VW also used a Resonator that worked with the Turbocharger on the MK5 GTI. If that is meant I understand what's wrong, I just got the Idea people were also referring to the sound outside the car, where you wouldn't hear these things, would you?
 
Must have missed that, but I do have the episode here, so I can watch it some time...

I think VW also used a Resonator that worked with the Turbocharger on the MK5 GTI. If that is meant I understand what's wrong, I just got the Idea people were also referring to the sound outside the car, where you wouldn't hear these things, would you?

Audi has put a speaker on the outside of the R8 E-tron and it plays a fake internal combustion exhaust note as it drives down the road. They call it Audi e-sound.

The e-sound wafts from a rugged loudspeaker attached to the car's undercarriage. "We designed it to handle as much as 40 watts, said Audi?s Axel Brombach. ?But during normal operation it ranges between five and eight watts. That's loud enough for nearby pedestrians and cyclists to hear the e-tron." As long as someone isn?t drowning it out with a bumpin? 1,000-watt aftermarket system.

Also, see edits above.
 
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The new Mustang also routes exhaust sounds into the cabin as well, but no one's solution is as tacky as BMW's. Yet.
 
It routs the sound into the cabin, not the exhaust (or intake air) itself.
 
Dammit. Maybe I need a "basically German" title.
 
The new Mustang also routes exhaust sounds into the cabin as well, but no one's solution is as tacky as BMW's. Yet.

I wouldn't call that a "fake" exhaust sound. Its justrouted in such a way that it gets enhanced for the cabin. I agree with you it is tacky, but its also really easy to remove. I'm kinda tempted to do so and see how it affects cabin sound. Saw a bunch of youtube videos saying it makes it sound great, but I don't have sound at work.
 
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The funny thing about the fake system in M5 is that when you lift off after accelerating hard for rather too long in a tunnel, you hear a surprisingly loud bang. It's rather convincing if you've rolled down your window, because you can hear it echoing, as you can hear many other sounds.

Yes, some of the sounds are probably fake, but after riding shotgun in F10 M5 for one evening I couldn't pick up the fake tones. I couldn't even notice there was something fake.
 
So this would be "real" exhaust sound?

Filmed when I welded my exhaust... Although it sounded nice at first, driving around like this would be a) deafening when you get above 40 kmh and b) lethal as all the exhaust gasses would find their way straight into the cabin ventilation :yucky:

I will try and make another video with the exhaust on, for comparision.
 
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The funny thing about the fake system in M5 is that when you lift off after accelerating hard for rather too long in a tunnel, you hear a surprisingly loud bang. It's rather convincing if you've rolled down your window, because you can hear it echoing, as you can hear many other sounds.

Yes, some of the sounds are probably fake, but after riding shotgun in F10 M5 for one evening I couldn't pick up the fake tones. I couldn't even notice there was something fake.

[video=youtube;jjIm_-P1m34]http://www.youtube.com/watch?v=jjIm_-P1m34[/video]
 
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