John is correct.

I hate to sound like a broken record because this is an issue that comes up time and again: get the BEST source audio you can because unsatisfactory source audio means a) unsatisfactory audio, or, at best b) an unsatisfactory "fix."

For live audio, if you didn't plug into the board or place wired or wireless mics in position to get good source, then I'm afraid you're hooped.

You can TRY EQ's etc, but you'll end up with something that sounds really over-tweaked. I would go near your source audio with a reverb, delay, chorus, or any other effect. You can't take our the source.

Your best bet, and I've done this in the past, is to use a secondary source and replace the audio in editing. Then, that gives you the option of using your camera audio, in a very subtle way, as "ambience" of the live room.

**...by getting rid of the natural reverb create by the mic picking up sound bouncing around the room at a distance?"

You will by no means "get rid of it," however it may be possible to lessen it a bit. 50 feet is a long way, even with a shotgun mic.

You are welcome to try my echo reduction technique that was posted some time ago, but as the previous poster said, you can't make good audio out of bad audio.

However, with a judicious application of the technique to reasonably acceptable audio, you may get some improvement. As always, "Individual mileage may vary."

Echo Removal Revisited

Back in my live audio days, I made lots of audio and video recordings of my bands, mainly for the bands to critique themselves. In smaller club situations, I was mixing for the room and not for the recording, so the mix from the soundboard was mostly kick and snare drum and vocals, with the keyboards lower in volume and the guitar and bass virtually non-existent because they were usually plenty loud coming out of the amps on stage and didn't need much sound reinforcement. I'd record the mixer output and also place a couple of microphones in the room and record them to another pair of tracks. You can either use a 4-track multitrack or just record the board mix on one stereo recorder and either another recorder for the audience mics or just use the camcorder and its mics.

The trick is to take the room mic tracks and slide this track up on the timeline during edit to make it match time-wise with the audio mixer tracks. Then I mix the room tracks in with the soundboard tracks. The level of the room mic tracks is a matter of taste. It really does make the recording much more listenable and doesn't require a bunch of additional gear, just a little extra time in post to sync and mix the tracks.

John