Gran Turismo's engine sounds (up to and including GT5: Prologue) are lack lustre at best quite frankly. I think by more clean and more comfortable you mean boring and sleep inducing... Its shocking the number of times I've fallen asleep whilst playing GT where I bet a large reason for it was the boring monotony of the engine sounds.
Now I hope GT5 will be a massive improvement in this regard, theres nothing more dissapointing to buy a muscle car etc... in game only for it to sound like another sewing machine/hair dryer. Forza is massively ahead in this regard and one of the first things I do when I buy a car in Forza 3 is to take it for a test drive, look around the interior (yes only front interior unfortunately but at least theres 400 of them), rev the engine and then floor it to bask in the lovely sound as the car takes off. I have never ever done that in GT? Why because the engine sounds suck arse.
I hope PD fix this, it doesn't matter if the handling is fantastic and the graphics are jaw dropping if they've still got the same engine sounds... Its no where near the defintive game (for me at least). Engine sounds shouldn't be underestimated.
Thats a Countach, I heard one in real life - Its the best sounding car I've ever heard.
GT3 and GT4 had a tendency to send me to sleep, too, but GT2
didn't. Given that they share the same engine sound samples, more or less, I can only attribute it to the wind and tyre noises - which makes sense; that kind of constant droning will send you to sleep.
Forza might sound better at first hearing, but there are some major flaws in their approach when you dig deeper. The first being that the samples sound the same irrespective of where you hear the car from - a real immersion killer for me. The second (for me) is their insistence on giving every car that silly warble. Basically, you can do much better than Forza for sound, and I hope PD realise this.
GT has always had poor sound, which is sad. but the driving is more important to me. if they did make the sounds better, it would add to the total immersion feeling of driving, which i believe is what they strive for. after all, this is a driving sim.
In retrospect, by today's standards, yes all GT games have "poor" sound. At the time, though, GT2's samples were about as visceral as it got (it was toned down for GT3, massively); GT3's surround sound was also another great achievement - I could tell which tyre was making all the fuss, which is important when you can't actually feel it.
We can complain all we want that GT doesn't sound how we expect it to, but I think PD are trying to come at it from a different angle, one which might prove fruitful in the end. We'll have to wait and see what these improvements are.
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On a side-note, I spent a lot of time yesterday listening to various cars from GT5 Prologue; the main offenders in that game are the engine notes (as opposed to the exhaust notes, since they are separate in this game - something that is still surprisingly rare)
They have a lot of whizz to them, and don't have any of that intake goodness (except maybe the Ford GT). I also made a point of turning it up nice and loud on TV speakers, and balanced it with a sub-woofer to my own tastes (which makes all the difference, there are some interesting hidden textures - Audi R8 is a good example).
Something else I noticed, is that most of the V8s (excluding the IS-F, which sounds very boomy but indistinct) have a
common sound to them...
This leads me to believe that the Prologue samples are recycled and remixed from GT4's samples to fit the car in question - that's quite an achievement in itself, if a little backward. My guess is they wanted to save the "proper" sounds for the final game, even back then.