Thursday, November 3, 2011

Reduce Noise In An Audio Recording

Reduce noise in your audio recordings.


The noise-reduction foam and expensive microphones you find in a studio aren't the only ways to eliminate noise in your audio recording. While these things certainly help, you can get a virtually noise-free recording in your own home with almost any microphone -- even the internal mic in your computer. Use a variety of techniques to naturally reduce noise while you're recording and eliminate noise in audio you've already recorded.








Instructions


1. Get rid of all possible noise in your recording space. Pick the least noisy area to record in. Turn off any fans, heaters, air conditioners and other nonessential devices. Even an extra laptop or idle gaming console makes noise, so if you're not using it, shut it off. Close the doors and shut the windows. Place your microphone away from any remaining noise sources, including power sources. Don't record next to a window, even if it's closed. Remember that your computer makes noise, too. Even sounds your ear can't hear will become noticeable once you amplify your recording. Finally, turn off any cellphones. GSM buzz can be picked up in your recording, so do not set the phone to vibrate. Turn it completely off.


2. Get as close to the mic as possible. Positioning for tonality and comfort has to be taken into consideration, but beyond that you simply want to get as close as you can. The closer the microphone is to the audio source, the less background noise will show up in the recording. Turning up your source will accomplish a similar effect. Simply speak louder, or if you're recording an electric instrument, turn up the volume. If your levels start clipping, bring the volume down on the mixer.


3. Tweak the EQ. After your audio is recorded, you can often eliminate noticeable buzz or hiss using the equalizer. If your mixer has equalizer presets, try playing with those before you start recording to see what bands you can turn down to diminish noise. If you're mixing digitally, you can record the audio straight in without any EQ and apply one during the editing process. Finding the right equalizer band to mix down is often a process of trial and error. If it's a hissing sound, it's going to be in the higher spectrum. If it's a buzzing sound, it's probably coming from the mid to lower spectrum. A graphic equalizer is a great mechanism to form a valley in the EQ and move it around until the noise is reduced.








4. Use a speech enhancer plugin. Any good mixing program has one; even something as simple as Apple's GarageBand can do the trick. Or, try searching the Internet for a third-party plugin. The speech enhancer will let you apply some quick tone settings to make a speaking voice sound more professional. More importantly, it will give you the option to dial back the more quiet sounds in a recording. This will help isolate the vocal and push everything out. While this type of plug-in is meant for spoken audio, it can be used -- with mixed results -- on any kind of audio.


5. Know your noise gate. The noise gate is your key to absolutely silent pauses and crystal clean audio. The gate takes out all noises under a certain level and turns them down however much you tell it to. If you find that your desirable audio never gets any quieter than -20dB, you can tell your noise gate to turn the recording down any time audio is not exceeding -25dB. You can even tell it how much to turn it down: all the way for a clean recording, or maybe just a little to allow some natural hiss in. The noise gate appears easy enough on the outside, but can be a little complicated to master. If your settings are too high, you will clip out parts of your recording, making it obnoxiously unlistenable.

Tags: noise gate, your recording, noise your, your audio, eliminate noise