This discussion is very interesting.
For a great example of a true next-gen sound engine, check out F1 CE PS3.
The dev's take advantage of Cell to calculate how the volume (db's) from the engine travel distances, hitting objects, how they reverb, echo, etc, affect the sound. In the past it was mostly faked. Going through the tunnel at Monaco with the V8 screaming at 19,000 rpms is an ogasmic experience btw.
The GT dev's already have good enough samples, they are translating it into a more advance level. The engine samples were actually quite compressed in all previous GT's, because of lack of processing power and storage.
If we look at stock mufflers on road legal cars, its quite restrictive in its design. Its purpose is to obviously cancel most the raw engine notes, so that the overall noise level is under 90db's (for most countries). GT's aim has always tried to simulate this. Unlike other games that try to add sfx, or record cars with aftermarket exhaust.
The fact is, most stock cars don't sound that intresting, or loud.
The main issue is, in all GT's, when you upgraded your exhaust system on most of the cars, you were getting interpretations. Its very time consuming to remove mufflers for hundreds of cars. Of course they also recorded some cars with aftermarket exhaust, or straight pipes when they could.
My main complaint is, they did not truely simulate the loudness levels between different exhaust systems/cars. From stock, to exteme loud F1.
For example, an F1 car at full trottle is approximately 150db! Just to give you an idea, a shot gun being fired is only about 130db.
In real life, if you drove an F1 car in a field of loud civics without mufflers, the F1 car would still overdrown them all. But not in GT.
I already know that he is imbarassed about the sounds, and for sure they are working on something new. GT HD is already a big improvement by using higher sampling rate. But you must have a good audio system to appreciate the differences.
GT HD is only the start, the new sound engine in the next version will be what the PS3 is capable of, like the story I told you of F1 CE.
Please discuss.
Dan.