Three Shapes of EQ
What graphic, parametric and shelving EQs each control, and how their moves differ on the same source.
Related
The question
Both EQs claim a 3 dB boost, yet a graphic, a parametric and a shelving band give different results. Choose the wrong shape and precise numbers buy nothing.
How it works
A graphic EQ divides the spectrum into fixed sliders, with centre frequencies and bandwidth locked; it is fast. A parametric band lets you set centre, gain and Q, and a higher Q narrows the affected range. A shelf raises or lowers everything above or below a corner frequency and has no peak. All three are filters; they differ in which dimensions you control.
Settings and what you hear
On a parametric band, 1 to 3 dB is already audible; above Q 4 the boost rings on one narrow band. A high shelf brightens the whole signal and turns harsh when overdone. A low shelf thins a source, and too much removes its foundation. Adjacent graphic sliders overlap, so one region often gets lifted twice.
What to listen for
Play a solo piano and listen first to the body around 200 to 400 Hz, then to key noise above 3 kHz. A narrow boost moves one small patch; a shelf lifts the whole cloth.
Common misconceptions
That EQ can fix anything, ignoring phase and resonance; that more sliders mean more precision, when fixed bands simply miss the frequency that matters.
Listen in the library
All tracks from midicn-lib — inline badge is the license tier (C1 commercial / C2 non-commercial / C3 study only).
Sources
- Huber and Runstein, Modern Recording Techniques, equalisation chapter — background checked, not quoted
- Sound On Sound, EQ Explained by Hugh Robjohns — definitions and typical ranges checked, not quoted
Used for fact-checking only; all prose is original.