Environment

We're not going to be doing enough live recording to touch on this.

A Talkback Mic specifically refers to mics that facilitate communication between a a studio performer and an engineer or producer outside the recording booth.

Throughout this page, and during any recording session, always remember one simple rule: ALWAYS retain your source files! You obviously will not want to keep completely botched takes but even if you have a "top 5" don't discard four of them just because you're confident about a single take. Even operations that you may think you'd never want to take back like volume correction or noise reduction should not be part of your raw files. Volume correction can be destructive and noise reduction can destroy subtleties you may want back later.

Keep the raw files. Always.

Best possible range

Clipping: When the peak amplitude of a waveform is higher than the threshold of the listener / listening device or when the recorded power level is higher than the output device can manage, resulting in lost information.

The primary thing to watch out for when recording is that the audio signal makes full use of the possible signal range. This can be as simple as watching the track meters and making sure of two things.

  1. Meters that go into the red (or maximum level) may be exceeding recodable levels. Information is being lost.
  2. Just as important however, is to make sure that the full range is being used. If it looks like a singer is using only the upper half of the meter more than 90% of the time, then you may need to adjust conditions so that they use more of the meter. This can often be as simple as moving the microphone further away from the source.
A signal wave which has had gain added in the second image. As you can see when the upper limit is reached the signal can not record information any longer resulting in "clipped" peaks.

Noise & static reduction

The subject of "noise removal" is kind of a catch all for various techniques involving different functions. Much of it might use the same techniques outlined in the "Filters" section since much unwanted noise is the result of a low amplitude background noise or certain frequency ranges.

Specialized plug-ins

The noise removal operations included in most programs are too complex to be done by hand. This is actually a good thing because it may seem possible to just "cut out" the sound you want from the noise around it but that approach will not actually affect the audio you kept. "Noise" does NOT only describe the signal AROUND the audio you wish to keep but the signals WITHIN the desired audio as well.

Here we have an audio clip of a with background noise that is unedited. And then two examples. In the first attempt we have simply silenced the signal around the SOUND to get rid of the more obvious

For the last clip we've actually made use of a noise removal algorithm (specifically the Audacity implementation).

It should be clear the second version is better.

Limiters / Gating

Limiters were explained within the Filter section so I won't regurgitate the same information here. I will say that, while they certainly have their place during live performances, limiters should have their use, well, limited during recording. It may seem an obvious choice to make the recording better but it may cause you to miss out on pros and cons of particular tracks.

There is sometimes a certain energy that comes with recording "in the moment". An excitement that can dull the senses to certain qualities or subtle sounds that you might not hear when you've retired to a quiet area by yourself to actually mix the sounds. These subtleties can be as simple as a breath or a vibration that you may not have picked up during the recording session that makes all the difference. You want to have the option of keeping these.

As such, if you do use noise gates when recording, consider constraining them to output monitor line only. You can always re-apply it later.

Normalization

Often when recording multiple clips, especially at different times, you'll run into the problem of input levels being different for each clip. This can be due to something as obvious as a sound source being closer to a microphone or even something unforseen such as an overly aggresive phantom power on a microphone.

Sometimes you may not want to just lower or raise the volume of each clip but want to try and recreate the full possible range of a your audio signal.