Isolating Specific Sounds – Is It Possible?

[Premonition2035]

I'm creating a weapon mod for Unreal Tournament 2004, where I'm recreating the Plasma Rifle from the Halo universe. I needed the weapon's original firing sound and I've never done this before, so I had to figure out how to record audio from my TV. Now I just need to edit it, and that's where Audacity comes in. The problem is that when I recorded the audio from Halo 3, I was unable to turn down the game's ambient sounds, such as the persistent rustling of the wind or far off sounds of combat. So I have all of this crap mixed in with the Plasma Rifle's shots and I was wondering, is it possible to isolate just the sounds I needed? Or do I have to live with these imperfections? Thanks in advance for your help!

[kozikowski]

Depending on the character of the shot, you may be able to take the waveforms apart and find the actual impact which will (or should) be a lot louder than the surrounding noise. However, you're never going to recover the aftershock, impact hangover, and echoes. Those will vanish in the game trash. So the original BLAM-bm-m tsh, tsh. is going to turn into a very artificial sounding BLAM [total silence].

No tools I know of will filter out an explosion or gunshots better than you can with the cursor and editing tools.

Koz

[Premonition2035]

Ah, okay. Knowing that certainly helps me. So the waveform is a compilation of the waves that represent the individual sound sources (so far as Audacity can tell), and not just one big mess in and of itself? I'm completely new to sound editing and I've been needing clarification on this point. If that's the case, how can I get in and manipulate the individual waves? I've been looking through the help files and I can't find anything along those lines. >_<

[steve]

So the waveform is a compilation of the waves that represent the individual sound sources (so far as Audacity can tell), and not just one big mess in and of itself?

No not really - the sound is one big mash up of all the sounds - that's why it is difficult to isolate a single sound.

What you can do, is to filter out frequencies that are lower (more bass) than the sound that you want (using the high pass filter in Audacity 1.3.6) and filter out the frequencies that are higher (more treble) than the sound that you want (using the low pass filter), then you can silence the sound before and after the sound that you want. This last step is where you loose all of the "-bm-m tsh-tsh" that follows the original "Blam".

You can try to artificially recreate the "-bm-m tsh-tsh" part of the sound by using echoes and reverb on duplicates of the original track, then carefully mix them in with the original "Blam" to recreate the "Blam--bm-m tsh-tsh" sound.

[Premonition2035]

Oh, so it is just one big mess. Okay. I downloaded Audacity 1.3.6 (I don't know which version I was using), but I'll have to experiment with the filters later. Unfortunately for me, I have finals to worry about over the next week. Anyway, thank you both, hopefully I can get my mod sounding as professional as possible.