Jason, try this tip that was on another Vegas forum some time ago. Good luck with it.
Mike
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I split the audio track into separate clips for each speaker, and opened in Sound Forge as take. First I normalised it as the levels were WAY down, then some Eq to kill anything not needed and add some boost at 100Hz and dips at the room resonance. Then used wave hammer at Smooth Compression preset. Saved it back to Vegas, then opened that take in SF as a take again and applied Wave Hammer at Medium Compression preset. Saved that back to Vegas and dragged that take into a new audio track. Then switched on Invert Phase.
Now at this point all you get is rubbish. Slide the track gain down on the highly compressed track, I found a sweet spot at around -12dB but it varied from speaker to speaker.
1. Select All, then Copy the audio.
2. Paste to a new track, invert the waveform, and apply moderate compression.
3. Reduce the new track volume so that a preselected “quiet” area is about 50% of the level of its corresponding area in the original.
4. Paste Mix the new track into the old. Renormalize if necessary.
There should be a noticeable improvement in clarity and echo reduction because you have applied negative feedback to the areas where the echo is most objectionable. Too high a compression or too high level of the feedback track will give a “pumping” effect, however.
I used this trick in Vegas and was amazed how clean I could get it by playing around with the compression release time and threshold adjustments on the alternate track. The release time adjustment was the biggest help in overcoming the acoustics delay and still preserving the proper dynamics in the main audio.
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