Any of you loyal GD readers done any work with vehicle engine sounds? If so, what is your technique? I havent experimented with it that much but I am about too and was curious if anyone had advice to offer. Here are my preliminary super basic technique: When the gas pedal is pushed down begin playing an engine sound, and tell the sound subsystem to play the sound with infinite looping. Then when the gas is let up, tell the sound subsystem to stop playing the sound. Each quantum tick of the vehicles, adjust the volume of the sound based on the current velocity of the vehicle. Like I said this is super basic, but the results is acceptable at the minimal level of acceptance.... (I have actually implemented this one) My thoughts are along these lines (as for enhancements): Have more than one engine sound and blend them together at different volumes based on the current velocity and *acceleration* of the vehicle. so when it is accelerating rapidly blend in a deeper engine rev type sound. Also add a variety of sounds, like one for when accelerating, one for when the gas is no longer down but the engine is on and the car is decelerating on its own (without brakes on), etc Are my basic techique and "enhancement" just totally off base here? am I going about this all wrong... it seems like a terribly complicated method but if there is one thing I have learned in the world of programming it is the simple method usually produces simple results.

you want to modulate the pitch, not the volume. The volume will be very slightly modulated by the amount of gas let in the engine. Actually, it should really be a very small filtering effect. The pitch is basically in sync with the revs of the engine, which in turn can be approximated to the speed of the vehicle and the gear ratio. Because the engine revs quite wildly, you can''t just use one sound for the whole rev range or it will sound crap. What I usually do is cross-fade several high resolution sounds, one for low revs, one for mid-range, and for high revs. They can blend seamlessly, although it is quite tricky to achieve.

The sound should not be really influenced by the acceleration of the engine or the velocity. As I said, a slight filtering effect maybe.

The lift-off sounds of an engine can be quite interesting. If you have a turbo, you should have a hiss sound when the turbo pressure goes down dramatically.