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Appendix Audio Terms

Beginner-friendly reference

Core Dynamics Terms

Compressor

Turns down loud parts so volume is more controlled.
Can make tracks feel tighter, smoother, and more consistent.

Limiter

A very strong compressor used at the top end of volume.
Helps stop peaks from clipping and sets a ceiling.

Gate

Mutes or reduces signal when audio falls below a threshold.
Useful for reducing bleed/noise between drum hits.

Normalization

Automatically raises audio so the loudest peak hits a chosen level.
Does not improve balance by itself; just changes overall level.

EQ and Filter Terms

High-Pass Filter (HPF)

Lets high frequencies pass and cuts low frequencies.
Used to remove rumble and unnecessary low-end.

Low-Pass Filter (LPF)

Lets low frequencies pass and cuts high frequencies.
Used to tame hiss/harsh top-end or push sounds backward.

High Shelf

Boosts or cuts all frequencies above a chosen point.
Good for adding air/brightness or reducing harshness.

Low Shelf

Boosts or cuts all frequencies below a chosen point.
Used for adding weight or cleaning excessive boom.

Metering and Space Terms

Term	Beginner Explanation
LUFS	Loudness Units relative to Full Scale; a perceived loudness measurement over time.
dBFS	Digital level scale where 0 dBFS is max level before digital clipping.
Stereo	Two-channel audio (left and right) that creates width and placement.
Mono	Single channel centered audio; useful for checking phase and translation.
Panning	Placing sounds left, center, or right in the stereo field.
Phase	Timing relationship between similar waveforms; poor phase can make sounds thin.
Headroom	Safety space below 0 dBFS so peaks do not clip.
Clipping	Distortion from exceeding maximum level; usually harsh and unwanted.

Dynamics and Processing Terms

Term	Beginner Explanation
Attack	How fast a compressor starts reducing gain after passing threshold.
Release	How fast gain reduction stops after signal falls below threshold.
Threshold	The level where a dynamic processor starts to act.
Ratio	How strongly compression is applied once threshold is crossed.
Knee	How gently or abruptly compression starts near threshold.
Makeup Gain	Output gain added after compression to restore loudness.
Gain Reduction	How much level is currently being turned down.
Transient	The short initial hit at the start of a sound.
Sustain	The held body/tail of a sound after its attack.
Transient Shaper	Tool that boosts/cuts attack and sustain directly.
Parallel Compression	Blend of heavily compressed signal with dry signal.
Saturation	Harmonic coloration that adds density, grit, or warmth.
Harmonics	Extra frequency content above the fundamental pitch.
Subharmonics	Generated low-frequency content below the original tone.
Resonance	A narrow frequency that rings out more than others.
Notch Filter	Very narrow EQ cut used to remove a problem tone.
Q (Bandwidth)	Width of an EQ band: narrow vs broad.
Mid/Side (M/S)	Separate processing of center (mid) and edges (side).
True Peak	Estimated inter-sample peak that can exceed sample peak.
RMS	Average signal energy used as a loudness reference.

Routing and Session Workflow Terms

Term	Beginner Explanation
LRA (Loudness Range)	How much loudness changes across a song over time.
Dynamic Range	Difference between quiet and loud parts.
Noise Floor	Base level of background hiss or room/system noise.
Dither	Low-level noise added when lowering bit depth.
Bit Depth	How detailed level values are in digital audio.
Sample Rate	Number of audio samples captured each second.
Inter-sample Peaks	Peaks between samples that can clip in playback.
Reference Track	Professional song used as tonal/loudness comparison.
Bus	Shared channel where multiple tracks are grouped.
Aux Send	Copied signal sent to shared effects like reverb.
Return Track	Channel that receives aux sends and outputs effects.
Insert	Processor placed directly in a track signal path.
Pre-Fader Send	Send level independent from fader level.
Post-Fader Send	Send level follows track fader changes.
Dry/Wet	Blend between original and processed signal.
Automation	Time-based control of levels, pan, and plugin settings.
Clip Gain	Gain change applied to an audio region before inserts.
Gain Staging	Setting healthy levels at every stage in the chain.
Unity Gain	Input and output level are effectively the same.
Mono Compatibility	How well a stereo mix holds up in mono.

Mix Translation and Tonal Vocabulary

Term	Beginner Explanation
Crest Factor	Difference between peaks and average loudness.
Brickwall Limiter	Limiter with strict ceiling that blocks overs.
Oversampling	Internal upsampling to reduce digital artifacts.
Aliasing	Unwanted mirrored high-frequency distortion artifacts.
Sidechain	Using one signal to control another signal’s processor.
De-esser	Frequency-focused compressor for vocal sibilance.
Exciter	Adds harmonics, often to brighten or add presence.
Glue Compression	Gentle bus compression to make elements feel cohesive.
Frequency Masking	One sound hides another in the same range.
Masking Release	EQ/arrangement moves that reduce masking conflicts.
Tonal Balance	Overall low-mid-high energy distribution in a mix.
Sub Bass	Lowest bass region, often around 20-60 Hz.
Low End	Bass range that provides weight and power.
Low Mids	Region often tied to body, warmth, and mud.
Presence	Upper-mid area affecting clarity and intelligibility.
Air Band	Very high frequencies that add openness and sheen.
Harshness	Unpleasant aggressive upper-mid or high frequencies.
Mud	Cloudy low-mid buildup that reduces clarity.
Boxiness	Closed, hollow tone usually in low-mids.
Boominess	Excessive low-frequency resonance.

Editing, Space, and Delivery Terms

Term	Beginner Explanation
Sibilance	Sharp 's' and 'sh' vocal sounds.
Plosives	Low thumps from consonants like P and B.
Bleed	Unwanted spill from another source into a mic.
Spill Control	Steps to reduce unwanted mic leakage.
Comping	Building one final take from multiple recordings.
Take Folder	Container that organizes alternate takes.
Punch-In	Recording over only a selected part.
Crossfade	Small overlap fade that smooths edits.
Edit Point	Exact cut/join location in an audio file.
Phase Inversion	Flip polarity by 180 degrees.
Polarity	Positive/negative orientation of waveform motion.
Null Test	Compare two signals by phase-cancel checking.
Stereo Image	Perceived width and placement of sounds.
Depth	Perceived front-to-back distance in a mix.
Front-to-Back Placement	How close or far a sound feels.
Reverb Tail	The decaying part of a reverb after source stops.
Early Reflections	First room echoes that define space cues.
Pre-Delay	Time between dry sound and reverb start.
Decay Time	How long reverb takes to fade out.
Room Tone	Natural ambient sound of a recording space.
Ambience	Perceived environmental space around a source.
Delay Feedback	How much delayed signal repeats again.
Slap Delay	Very short delay used for thickness.
Tempo Sync	Effect timing locked to song tempo.
Tap Tempo	Manual tempo entry by tapping rhythm.
Meter Bridge	Grouped meter view for many channels at once.
Peak Hold	Meter mode that keeps peak value visible.
Headroom Margin	Intentional level buffer before clipping.
Ceiling	Maximum output level set in limiter/master.
Master Bus	Final stereo channel carrying the full mix.
Print	Render processed audio to a new file.
Bounce	Export audio from session to file.
Stem	Grouped export such as drums, vocals, or music.
Print Through	Render audio while effects chain stays active.
Bypass Gain Match	Compare processed/unprocessed at equal loudness.
A/B Testing	Switching options for objective comparison.
Ear Fatigue	Reduced accuracy after long loud listening.
Translation	How well the mix sounds across different systems.

Beginner Rules of Thumb

Fix balance first, then process.
Use small EQ/compression moves before big ones.
A/B bypass often at matched loudness.
Check your mix in mono and at low volume.
Leave headroom and avoid clipping on buses.
Trust references and your ears over visuals alone.