Hi Loreta I'll address the recording good audio best practices that I follow. These have not let me down, but when I have NOT followed them I always end up with poor audio.
First, you need to get the mic as close to your talent as possible. Get a boom pole and position just out of camera frame above the speaker. This will ensure the most signal the mic is picking up is from the source you want - the talent on camera. Second, use a good uni-directional mic. Also called hypercardioid. Most (if not all) video shotgun mic use this response pattern. What this means is the mic is 'tuned' if you will, to only accept sounds coming in from a specific direction - uni directional. Most cheap dynamic mics and the on-board mics are omni-directional. That is they accept sounds coming in from any/all directions. So you end up with a recording that not only captures the sound of your talent, but also the sound of all the noise in the room. As has already been established by other posters here, a room is never silent. It amazes me when I listen thru headphones how much noise there is in a basic office setting. And these mics pick up EVERYTHING. Another thing, what kind of surfaces are in the room you are shooting in? Hard surfaces (walls) will reflect sound badly making the talent sound boomy and amplify the room tone. Floor with carpet is much better than hard surface floor, it is softer and will absorb reverberations. Still, throwing down blankets below and in front of your talent will dampen reverb's. and if you can find a room with soft surfaces, curtains, objects in the room to break up the hard flat surface, this will help minimise the room reverberations. So by using a hypercardioid directed straight at your talent from a very close distance, you have a really good chance of capturing only the sound you want, and minimizing the sound you dont. This makes it much easier to post the audio as there is less unwanted frequencies to filter out, thus leaving the frequencies you want alone. The alien effect you talk of is likely some odd filtering of frequency ranges of the voice that have been eliminated. Most human voice is in the range of 1500-4000khz. If you mess with those, or freq's close to them (not mention the harmonic freq's) you will alter how the voice sounds. Usually you can filter out below 90hz and over 10,000khz will little detriment. And this will clean up hum and hiss quite a bit. There is a typical hum at 60hz that is the electrical interference (US electrical circuits run at 60hz) and this can be filtered out with a notch filter in post. But really with good recorded audio, you should have little clean up to do in post. Garbage in, garbage out. I hope this makes some sense. Feel free to ask specific questions about an individual point and we can get you through it bit by bit. This is a topic that entire books are written on. Check out Jay Rose's columns here http://www.dplay.com/tutorial/column.html Adam Influxx Media Production --- In [email protected], "loretabirkus" <loretabir...@...> wrote: > > Hi..I know..I was asking tons of questions about sound/hum noise, etc. At > least I figured out that it's not my camera that makes that hum/static noise, > and it all depends on the environment I'm filming. > > My questions would be: > > 1. Besides recording 10-15 sec of the natural ambient sound and trying to > clean it during editing, is there any way to record it with minimum of it > during filming? Do you have any secrets? Do you prepare the room somehow so > that the voice could bounce back softly? None of my shot guns have been able > to perform to the highest noise elimination level. > > I try to place a mic as close to the speaker as possible (usually on a > separate tripod, don't have a boom pole yet) and adjust the volume level so > that it doesn't pass further than -6-8 db. But I still get that quiet natural > background noise. > What do you do in this case? Do you just leave it or do you clean it? > > 2. Which type of lavaliere mic would you recommend: wireless or cabled one? > What brand? Which ones are best in terms of noise cancellation? I'm kinda > glad I didn't buy anything, now that they're changing the rules for the 700 > mHz frequency type mics. > > Thanks. > > Loreta > > p.s. if you have any good forums that I could check out as well, please let > me know. I'm unlucky finding the ones that would answer my questions. >
