Dear LFSers,
Here are a few questions about the sound of an engine. In particular the sound of a V10 Formula 1 engine.
I'm a composer and for a music piece I'm writing I want to show the way I sometimes hear an engine: as music. I want to look at an engine in a musical way.
There are 2 reasons I'm picking a V10 engine: nostalgia (do I really have to explain this one?) and a more musical reason. Every sound is made up of multiple different sine waves: harmonics. Every wave can be seen as a musical note. In a V10 there are 2 waves which are very prominent. The fundamental (the bottom note), which I think is basicly the rpm (18000 rpm = 300 rotations per second, or Hz). The other one, appearantly, is an octave and a third above that one. If the bottom. Note is 300 Hz, or just above a D4 the other note is just above an F#5, around 750 Hz. But why?
This blog explains a few things.
http://formula1guitar.blogspot ... years-ago-new-engine.html
From what I understand, a cylinder makes an explosion every other time it makes 2 rotations. So, if the fundamental is 300 Hz, you get 300 / 2 * 10 = 1500 Hz. But that's twice the frequency of what you hear. Why? How does he arrive at that other note, 750 Hz in my example? And, if it does make 1 rotation every other time a cylinder fires, do you hear that note (150Hz, a D3) too? And what exactly ARE those sounds?
Am I right when I say that that 1500Hz is made up of 1500 explosions per second? What is the sound of one rotation? How does a single explosion from a cylinder sound? What makes that explosion? The fuel combusting, right? So those 2 notes aren't pure sine waves, they are much more complex. They are made up of explosions, each with their own set of harmonics.
And then there are the other sounds. In what way does the exhaust change the sound? Does it resonate, depending on the length and width of the pipe? How can I calculate that? Which other sounds are there? How does the gear sound? Where does that sound come from? Where does that backfire sound come from? Why does it backfire? Of course, in those days they had traction control. What makes that sound?
I realize this is all quite technical and goes quite deep. I'd like to create a full understanding of the sound. Maybe even to recreate the sound. I tried to fiddle around with LFS' sounds. With that I think I got a fundamental, then the 1st harmonic an octave up and then a second harmonic another octave and a third on top of that.
Who can help me with this? Is there anyone who can explain a few things about the way engines work, or about synthesizing a car engine?
Some other intersting things I found so far:
http://www.youtube.com/watch?v=Iyur9neCmPs
http://youtu.be/DzhFRpJHAwQ (he also explains a bit about the major 3rd note).
I would love to hear it, if anyone knows something about this. Thanks!