The world of audio recording, mixing, and production is difficult not only because of the complicated equipment and processes, but also because at the most basic levels it is a series of technical and scientific concepts and labels that people are not usually familiar with. The audio mixing terminology itself is often a barrier to understanding the basic ideas for audio recording and producing. Here are some of the more important and common audio mixing terms that a person would need to know when trying to process audio.
A decibel is a unit of measurement that is used to measure “sound pressure level,” also called SPL. At a level of zero decibels there is no sound pressure that is being read, which indicates absolutely nothing living or able to produce sound. People talking at a normal level is usually at 60 decibels, or db. The SPL is measured by a VU meter.
Sound is where molecules of air gasses in the area move around in a specific vibration. Frequency is a term for the number of times per second a specific sound tone is vibrating. For example, a tone at 550 Hertz, the measurement of frequency, vibrates 550 times per second.
Frequency range refers to the range of frequencies that humans can hear. This frequency range goes from 20 Hertz to 20 KiloHertz, which is 20,000 Hertz. Frequency range does not just mean the human ear but also audio recording or measurement equipment that can read the sound.
Dynamic range is somewhat similar to the frequency range, though it does the range in a less numerically based system. Dynamic range simply means the sound range from absolutely quiet to absolutely loud. This is a more relative scale, but still indicates a range.
Sound Reflection and Refraction
Sound reflection includes how a sound wave is affected by a surface barrier where it is bounced and reflected. Sound reflection is then different than sound refraction where the wave of the sound is bent and altered when it goes through a barrier or surface. The nature of this depends both on the sound and the surface or barrier.
Low and High Pass Filter
A low pass filter is often used in audio mixing during post-production. A low pass filter will allow low tones pass through while high tones are filtered out. This is done in the case of audio interference or noise that fits mostly into the high areas. If the reverse is true then you can choose to use a high pass filter to maintain the high range sounds and filter out the low. Noise often fits into one of the two categories so these may be one of the first places an audio mixer may go.
Compression Threshold and Ratio
The compression threshold, often just called threshold, refers to where the audio starts at compression. The ratio is simply how much compression is going to be applied after the compression threshold has been determined.
Delay is, like it seems, a delay in the sound. This can be a type of audio effect that creates the sound of an echo or reverb of some sort. Expect for audio delay to create an alteration on the audio.