A Trio of Porsche 911s - click above for high-res image gallery

And if you get 'em all right, you get a chance to win your way into a Porsche 911 Evolution driving course. Which, we have to say, is pretty dang cool. Here's how it works. Porsche has the challenge broken up into five categories. You hit play and guess which engine you're listening to. We went ahead and gave it the old college try and, uh, it's incredibly difficult. Like, we bet that Porsche mechanics would have a difficult time getting all five correct.

But never mind that, because it's fun! The first category (Carrera) wants you to guess between a 964, a 996 and a 997. Second is "Classic" where you must distinguish between a RS 2.7, RS 3.0 and RS 3.8. Good luck with that one. Next up is "Race Derived" and the choices are 964 RS 3.8, 996 GT3 and 997 GT3. Hard, right? Because air-cooled boxer motors pretty much sound alike, even when they get water cooled. Well, actually...

The test now turns difficult, as the next category is "Turbo." This is especially hard as most Turbos do little more than shuffle about town from mall to mall -- meaning it's rare to hear one at full clip. And you've got to distinguish between the 930, 996 and 997. Lastly, you have "Motorsport," and whether or not the car is the 935, 911 GT1 or 936 it don't matter, as the sound is just glorious. See -- we mean hear -- for yourself.


Related GalleryPorsche 911 Evolution Competition

[Source: Porsche]