• Eq (short for equalisation) is the process of adjusting the volume of specific frequencies within an audio signal. If a volume fader controls the level of the entire sound, an EQ is like having a hundred tiny faders across the frequency spectrum.

  • Reasons to use EQ:

    1. To Remove Nasty Frequencies: Eliminating resonances, ringing and annoying frequencies.

    2. Enhancing Ear Pleasing Frequencies: Bring the best out of individual elements.

    3. Creating Space for Clashing Instruments: Carving out space for instruments fighting for the same frequency range.

    4. Achieving Sonic Balance: Ensure mix translation on different playback system.

    5. Creative Effect: For sound design usage.

  • Basic Controls Found In EQ:

    1. Frequency (hz): The center point of selected frequency where you’re going to boost or cut.

    2. Q Value (Bandwidth): A variable that control the range of frequencies you’re going to boost or cut.

    3. Gain (dB) : A volume knob for the selected center frequency point.

    4. Slope (dB per octave): Controls how quickly you want the frequencies to reduce at each octave.

  • Basic Filter Types Found in Most EQ:

    1. Bell or Peak Curve: Boost or cut specific frequency range in a bell shape curve.

    2. Low Shelf: Boost or cut everything below targeted frequency.

    3. High Shelf: Boost or cut everything above targeted frequency.

    4. High Pass Filter (HPF): Cutting off frequencies below targeted frequency, leaving every frequencies above the cutoff point unaffected.

    5. Low Pass Filter (LPF): Cutting off frequencies above targeted frequency, leaving every frequencies below the cutoff point unaffected.

    6. Notch: A very narrow cut used for eliminating specific resonance, ringing or annoying frequency.

  • Common EQ types and its examples:

    1. Transparent EQ: An EQ that preserves original quality of the incoming audio signal. Eg. Fabfilter Pro-Q 4, Kirchoff EQ, Ozone 12 Equalizer.

    2. Character EQ: An EQ that imparts pleasing frequencies (colouration/saturation) to the incoming audio signal. Eg. UAD Pultec Passive EQ,

    3. Dynamic EQ: An EQ that listen to the incoming audio signal and raise or reduce the gain on a set frequency. Eg. Fabfilter Pro-Q 4, Kirchoff EQ, Ozone 12 Dynamic EQ.

    4. Parametric EQ: An EQ that has lots of control. Eg. Fabfilter Pro-Q 4, Kirchoff EQ, Ozone 12 Equalizer.

    5. Linear Phase EQ: An EQ that avoid phase distortion due to computational processing delay. Eg. Fabfilter Pro-Q 4, Kirchoff EQ, Ozone 12 Equalizer.