EQ Frequency Guide Calculator

Mud lives in different places for different sound sources because it's caused by buildup around each instrument's own fundamental and lower overtones -- a muddy vocal is typically cleaned up by cutting around 300 Hz, while a muddy kick drum is more often cleaned up around 400 Hz, a higher frequency reflecting where boxy buildup sits in a kick's tone rather than its low sub-bass thump. The calculator looks up a frequency specific to both the instrument and the complaint together, rather than applying one generic "mud frequency" to everything.

The calculator suggests a Q of about 2.5 for a small room, dropping to roughly 1.0 for a large room -- meaning the recommended EQ cut is more than twice as narrow in a small space. Small rooms build up sharper, more resonant problem frequencies from close-boundary reflections, so a tight, high-Q notch targets the issue without removing tone from the surrounding frequencies the way a wide cut would.

Mostly no, with one exception. For three of the four problem areas -- Muddy, Harsh, and Thin -- the cut frequencies this calculator suggests sit in the low-to-low-mid range where buildup accumulates, while the boost frequencies sit much higher, typically in the presence and air bands where clarity and sparkle live. Boomy is the exception: since boominess is itself a low-frequency problem, both the suggested cut and boost sit down in the low end for every instrument, and the boost frequency actually comes in lower than the cut frequency rather than higher. Either way, cut and boost are kept apart on purpose -- overlapping them would mostly cancel out -- it just doesn't always mean the boost sits way up in the top end.

Not necessarily -- the calculator returns both a cut and a boost frequency as independent starting points, but only one is usually needed to fix a specific complaint like harshness or thinness. Applying an unnecessary second EQ move can just as easily introduce a new problem as fix the original one, so treat each suggested frequency as an option to try and evaluate by ear, not a package deal to apply together.