To be honest the sound file was pretty easy, mainly because I used to do them for my old Elmod systems so I knew what it was I needed to aim for and how to get there. The IBU processes sound files in a different way, but uses the same format, so it was just a matter of figuring out what I needed to do to adapt my source sound file to the IBU way of doing things.
It is swings and roundabouts, the IBU is way simpler, but as a by product it also restricts opportunities to do what the Elmod did. To 99% of IBU users this won't matter at all as they will use library sounds, the same can also be said of Elmod users.
As an example, the IBU switches between sound blocks depending on stick positions, this is evident when trying to use radio chatter. The voice gets cut off as soon as I move the stick back to centre. There is only one turret rotation sound slot that I can use so I get the same sentence every time I rotate the turret, or part of a sentence if I return the stick to centre.
The difference with the Elmod system is that I could have 6 different sounds on the turret rotation, and they would play randomly, as well as play to completion regardless of where the stick was. This meant that I could flick the stick sideways to start a sound block and it would play whatever I had in the turret rotation sound section, randomly, and carry on playing it until it finished.
Without going into technicalities, the IBU makes creating engine sounds much easier, the Elmod makes creating engine sounds rather more time consuming, but gives a better result.
I guess its the difference between 2 channel sound and 8 channel, it's also the difference between £100 and £140.
I still need to re-do the main gun sound, it cuts off too soon, I need it to fade out as the shell disappears into the distance. I could also make the gun louder by reducing the volume of the engine sounds.
I will get back to it at some point and finish it all off properly.
RobG