A Clark is hard coded, and the gun sounds are audible when the tank is running.
Elmod sounds are in a different ballpark, powerful amp, multi channel, and studio produced sounds running through some complex onboard systems (Only on Fusion systems running their NextGen sounds - the others are 22mhz 8 bit mono).
IBU makes use of recorded sounds. As many who have delved into the sound files will know, these are 22mhz 8 bit wav files.
WAV files are the highest quality, but also the biggest memory hoarders. They are uncompressed to avoid losing quality.
However sound files are a bit of a liability. Take You Tube as an example. Someone makes a video of a tank, and they upload it to You Tube. The video may have been recorded in any one of the multitude of formats using any number of codecs. To speed up the upload time they may convert the video into a format that You Tube likes, this means compressed files, and loss of quality.
You Tube then converts that file into its own format, so more loss of quality.
You spot the video, and download it. Choose the wrong download format and the quality drops again.
Now its on your pc, and you extract the audio using whatever software you choose, another format, and a bit more quality gone.
Then you load the files into Audacity, and save the reworked sounds back into 22mhz 8 bit mono sound, so whatever sounds you started out with, there has been a significant drop in the overall quality of the sounds, quite apart from which the sounds are now in mono and being reproduced through a tiny onboard amp, rather than through a pc soundcard and stereo speakers.
I know from experience that no matter how good the original sound source was, by the time I have run through this little lot, all I am left with is something that sounds vaguely like what I started out with. The only way around this would be to stand next to the real thing with a quality recorder that recorded directly into 22mhz 8 bit mono sound, and with sound levels tuned to perfection.
Ok, so now we know that we aren't going to get concert hall quality from this little nightmare, we have to make best use of what we have got. The first step is to only use You Tube files that are recorded without background noise, these are very difficult to find.
Download the video and sound separately, I use a Firefox add on that downloads You Tube videos, but that allows me to select the quality of the download, or just the audio, and to select the format. This way I have the best starting point possible.
Next step is to import the file into Audacity.
Switch the stereo to mono, that way I am closer to hearing what I am going to end up with.
Next take a look at he waveform, if the peaks don't touch the upper/lower limits then the sound can be amplified without distortion. Go into effects and amplify it a little at a time so that the peaks are as high/low as they can be without touching the limits. If the peaks hit the limits they get clipped, and that is what reduces the clarity of the sound. You need all of the peaks and troughs to keep the range in the sound.
Tank sound systems change the range of the sound, so try playing it back with different settings on bass and treble. You will lose the sound detail as soon as the file diminishes, like it is does at the end of a gun fire. There is nothing much you can do about that, we are working within very limited parameters here.
A pc will play the whole range and everything will sound great, but the tank is a different ballgame. Mono sound, small amp, small single cone speaker, a speaker box that is probably home made, and it is inside a plastic hull that may or may not have direct access to the outside air. Speakers vibrate air, anything that bounces back or can't get out will diminish the quality.
To get a gun fire audible over the engine requires the gun amplification to be louder than the engine amplification. Though if the board is doing too many things it can't always allocate resources to do everything at once, hence the gun sound disappears. When I make sound files I dispense with as many sounds as possible, so tracks squeaks are usually deleted.
Another option to consider is merging sounds in Audacity. As an example, merge engine sounds and track squeaks, that way its only playing one sound file instead of two, but you will still get both sounds. You can do the same with crew voices, merge them with turret rotation sound sounds, or elevation sounds, and you will hear the voices when the turret rotates etc. If you have a TD with no turret, you can replace the turret rotation sounds with anything you want, and simply play them when you push the stick sideways, you can stick all sorts of battle sounds on a tank this way.
I hope this helps someone, making sound files is a learning process, a lot or trial and error, but having sounds that no one else has got is like having a tank that no one else has got.

Rob
PS - The sound comes out of the speaker, it has to be in an enclosure and preferably airtight so that only the vibrating cone is emitting the sound, anything that comes out of the back of the speaker will cause distortion. The only two decent speakers that I would recommend are Tamiya or Visiton FRS7's/FRS8's, as they match the output and range that the tank systems produce.
http://uk.farnell.com/visaton/frs-7-4oh ... dp/5095487