just for fun, making an inline 4 sound like a v8
 

I just wasted 4 hours of my life making this rather fun set of sound clips:
faux engine sounds.zip

I had this idea, that one could put a resonance tube into the exhaust at the correct length to double the frequency of the exhaust note and make a "lowly" 4 cylinder sound like an exotic! At 6000rpm on a 4 cylinder engine, this is about 48cm of pipe if you can keep the pipe at ~150C (no exhaust flows through so I imagine it's not that hard), and at 9000 this shrinks to 32cm.

Of course, a moving pipe section or plunger is a bit difficult, so I wondered what effect sticking a couple of butterfly valves in there would do...I started with a sound clip of an AP1 S2000 (I know, 9000rpm isn't realistic on most street cars but still), and overlayed the sound with fade in/out and set the frequency perfectly out of phase when the engine hit 6000, 7500, 9000, and then 6000, 7000, 8000, 9000 (approximately, this is all by ear).

The file named "3 valve" simulates using 3 valves to vary the tube length, and the file named "2 valve" simulates using 2 valves (for 3 possible tube lengths). I didn't simulate harmonics because that would've been pretty hard, but I think I got a pretty interesting sound out of this! Sounds pretty much like a V8 from 6000 up.

I was inspired by hearing clips of the old CBR250RR that hit 20000rpm, at which it sounds just like an F1 engine.

Enjoy :)

Well!!! Much talk has been made of how to let pedestrians know an electric car is there
at crosswalks.

Maybe your 4 hrs. isn't a wast of time.

Around here we have the fake bird sounds so you know when to walk.

Maybe we need the sound of a Grizzly gradually getting amped up in anger, or a rattler about to strike.

Imagine if car makers could pick their own sound like you can pick a phone ringtone.

The variety would be interesting unlike the single 3rd brakelight we are stuck with.
Anybody remember the Olds Tornado with 2 extra brakelights for style's sake???

Have you heard the new dodge dart rallye? Sounds sweet.

Ahem.