Acoustic treatment – Panels made of fiberglass (among other things) that are hung from walls in order to deaden room reflections and balance the frequency response of a room. Treatment is very important when recording or when mixing using speakers.
Attack – This refers to 1) the very beginning of a sound, and 2) the amount of time it takes after a sound begins for a sound processor to begin working. Usually measured in milliseconds (ms).
Bandwidth – The amount of space on the frequency spectrum that the sounds of an instrument are being produced at. For example, an average electric guitar has a bandwidth of 80Hz-5kHz, as the instrument cannot produce sounds above or below those frequencies.
Decay – How fast a sound fades from a certain loudness.
Decibel (or dB) – the main unit of volume measurement. A dB is relative, as there are several different “scales” of dB’s that are used in audio (dB-FS being the most common, along with dB-VU, dB-RMS, and dB-LUFS). Each dB scale has a certain function in audio.
Dynamics (or dynamic range) – The loud and soft points of a sound over time. The higher the range, the more difference there is between the loudest point and the softest point.
Feedback – When a signal is sent through an amplifier and into a microphone, which picks up the sound and sends it back through the amplifier, and so on. The loop of sound creates high pitched whines. Also refers to the parameter on a delay that adds more repetitions of the sound.
Flat – A word used to describe a piece of gear that has no coloration to the sound; what comes in is what comes out. Most digital gear has a flat response, whereas most analog gear does not.
Fundamental – When a sound is produced by an instrument, a series of harmonics are created that determine the tone of that sound. The lowest (and loudest) of those frequencies is the fundamental. It is the primary harmonic of that sound.
Hertz (or Hz) – The unit of measurement for frequencies. After 1,000Hz, the unit is measured in Kilohertz (or kHz).
Kilohertz (or kHz) – 1000x the unit of measurement for frequencies. 1 kHz = 1,000 Hz.
Masking – The phenomenon when one’s perception of one sound is affected by the presence of another sound. Basically, if two sounds are present in the same frequency range, then it will be harder to distinguish between the two. You want to avoid masking in order to get your instruments to sit well in the mix.
Overtone – When a sound is produced by an instrument, a series of harmonics are created that determine the tone of that sound. All of the harmonics that aren’t the lowest (known as the fundamental) are known as overtones.
Phase – The nature of the location of two similar waveforms in relation to each other. If two similar waveforms are “in-phase,” then the peaks and troughs of the waves are lined up with each other. If the waveforms are “out-of-phase,” then the peaks are in line with the troughs. This causes low and low-mid frequencies to get lost. Ultimately, out-of-phase waveforms sound bad.
Polarity – The “direction” of a waveform. When you “flip the polarity” of a waveform, it turns the waveform upside down. Basically, the peaks are where the troughs once were, and vice versa. Polarity buttons (sometimes called phase buttons) are common on audio interfaces to keep stereo inputs in phase with each other.
Room resonances (or Standing waves) – Every room has frequencies that build up more than others. These frequencies can mask the pleasant elements of a sound. By finding these frequency build-ups and cutting them using an EQ, we can improve the sound of a recording.
Sine Wave – A perfect soundwave with no harmonics or overtones. These cannot be produced in nature, but are the basis for many synthesizers and effects.
Timbre – another word for tone.
Transient – The very beginning section of a sound. Also known as the sound’s attack. It’s the loudest and most percussive part of the sound.
Waveform – The shape of a sound wave.
Wavelength – How long a wave is. The shorter the wavelength, the faster the wave.