This original version of this tutorial I found ages ago on the Massassi Temple site. It was written by Tobbi Dala and the original version of the tutorial can be found through this link. What I've done here is to do some minor spelling corrections, add new pictures that show the tutorial using the most current version of Goldwave (the main program used in this tutorial) as of 20APR2017, and to provide new permanent links to 2 audio files needed for the tutorial.

After the large tutorial quote, I'll be showing examples in this tutorial in action. I asked Zhaboka to record some lines that would be used to illustrate the tutorial in action and he was kind enough to assist. (Zhaboka's line replaces the line that the original tutorial grabbed from Mysteries of the Sith.)

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So, you are tired of the Stormtrooper's dialogue, or it just doesn’t fit the action of say your new cutscene? Well then, you are fortunate! Fiddling around with various sound software the other day, I finally discovered a way to make a normal sounding sound file have that filtered sound of a stormtrooper. Now I’m sure that some of you already know how to do this, but I had never gotten my stormtrooper sounds to be this precise. Also included are ways of making garbled radio chatter like the x-wing pilots in Star Wars: ANH, and an easy way of making sure your new WAVs have the correct header when saving it. So - without further ado - here’s some tips on how to make your own filtered WAVs:
OK, you need a program for this. It is a sound editor called Goldwave, you can download here. Now remember that this sound editor is a shareware program, you can use all the fancy stuff, save your stuff and so on, but it shuts down after you have used it for a while. Not a problem though, just open it again.

 

Remember, if you’re going to buy an audio shareware prog, this is it.
I have mostly all of the fancy sound stuff out there, but this one is still my favorite since the days of Dark Forces because it can handle a variety of sound formats including Dark Forces VOC files.

 

Note: For this Tutorial, I’m using Goldwave version 6.27. And I’m using sounds from both “Jedi Knight” (JK) and “Mysteries of the Sith” (MOTS), since the stormtroopers in MOTS don’t have any "clicking" sounds when they speak mysteriously enough...
1. Grab i00s111z.WAV from here.
2. Grab Sample.WAV from here. (This is our unfiltered test line - provided by Zhaboka.)
3. Open them both up in Goldwave, and this is what you should see:

 

 

4.Select the unfiltered sample - Sample.WAV - which we will making into a Stormtrooper. Access the "Effects" pull-down menu from the top toolbar. Now choose "Filter", followed by "Bandpass/stop"
This is the filter that you will use:

 

5. For this particular WAV file, change the presets as shown. Just set it to "Dynamic" and the steepness to 2, that should do it. Now these variables vary on other sound files, you are going to have to experiment with them yourself. And there are loads of other FX you can come up with, com radio chatter and so on. I myself managed to fix up a filter that sounded exactly like the Rebel pilots garbled radio communications with each other on the attack of the death star. I’ll show you how to do that further down.

 

OK, take a listen to the new rebel commando WAV - it sounds like a Stormtrooper, right? Well, almost. First, we have to polish it up a bit. Select this part of the i00s111z.WAV, copy it and use "paste at beginning" on the Sample.WAV, like this:

 

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6. This lets the our new Stormtrooper WAV have those clicking sounds that are missing from our Sample line. Repeat it with the end "click" noise from the i00s111z.WAV file, like this:

 

 

Highlight the whole section by pressing "CTRL" and "A" and - for this sample - save as "result"

 

There you go, with the filter laid and both clicking sounds, the end result should look something like this:

 

 

OK, that should be it! You may find it a bit too quiet, so did I. that's easy to fix though. Just raise the volume of it in Goldwave.

 

Oh yeah, the garbled X-Wing radio communications a la Star Wars: A New Hope ... which makes the sounds a bit Wobbly. (Watch the film again, if you can’t remember! )
That's another filter called "Mechanize." To access "Mechanize", once again go to the "Effects" pull-down menu from the top toolbar. Now choose "Filter", followed by "Bandpass/stop" I recommend testing which Modulator you wish to use: Sine, Triangle, or Square.

 

 

This one is easier to apply, but harder to get it right, since there are fewer options. On some sounds, you have to use another filter to make them more radio-like.
GoldleaderGoingIn.wav here was a Stormtrooper WAV which I used mechanize quality 20 on. Since it already had a radio-ish quality to it, it sounded exactly like the rebels
in A New Hope.

 

Well, that's it really. Experiment wildly, as the results can be weird!

 

Happy editing!

Now here's what the sound files sound like - so you can hear it for yourself! The lines will first appear without the filter and then with the filter.

Special Thanks to:

Tobbi Dala (of Massassi Temple), the original creator of the tutorial.
Zhaboka: For recording new lines.
HK-47: To extracting the line as it appeared on the original tutorial. Though it wasn't used here - as I used Zhaboka's new lines instead - the effort was and is most appreciated.