Important Frequency Ranges
Sub-Bass - The very low bass between 16 and 60Hz which encompasses sounds which are often felt more than heard, such as thunder in the distance. These frequencies give the music a sense of power even if they occur infrequently. Too much emphasis on this range makes the music sound muddy.
Bass - The bass between 60 and 250Hz contains the fundamental notes of the rhythm section so EQing this range can change the musical balance, making it fat or thin. Too much boost in this range can make the music sound boomy.
Low Mids - The midrange between 250 and 2000Hz contains the low order harmonics of most musical instruments and can introduce a telephone like quality to the music if boosted too much. Boosting the 500 to 1000Hz octave makes the instruments sound horn like, while boosting the 1 to 2kHz octave makes them sound tinny. Excess output in this range can cause listening fatigue.
High Mids - The upper midrange between 2 and 4kHz can mask the important speech recognition sounds if boosted, introducing a lisping quality into a voice and making sounds formed with the lips such as ‘m”, “b,” and “v” indistinguishable. Too much boost in this range, especially at 3kHz, can also cause listening fatigue. Dipping the 3kHz range on instrument backgrounds and slightly peaking 3kHz on vocals can make the vocals audible without having to decrease the instrumental level in mixes where the voice would otherwise seem buried.
Presence - The presence range between 4 and 6kHz is responsible for the clarity and definition of voices and instruments. Boosting this range can make the music seem closer to the listener. Reducing the 5kHz content of a mix makes the sound more distant and transparent.
Brilliance - The 6 to 16kHz range controls the brilliance and clarity of sounds. Too much emphasis in this range, however, can produce sibilance on the vocals.