Why does subtractive EQing increase the gain?

Discussion in 'Production' started by padders, Nov 20, 2010.

  1. padders

    padders Member

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    Pretty much what the title says. I was eqing a kick the other day taking some low end out but doing this increased the gain. Surely removing frequencies should reduce the gain or am I missing something? Attached are some screen shots with the eq bypassed and on.
     

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  2. Cat Gas

    Cat Gas Aka Basis

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    basically, imagine the waveform thingy hitting your spectral analyser. The peak (lets say its around 40hz) hits the highest. As a result the whole sound must be decreased in order to compensate for the peak, to keep it below 0db. However if you cut out or lower the peak (at 40hz) the rest of the sound can be louder overall, while still remain below 0db. However you are cutting out some of the frequencies, changing the sound slightly.

    I hope that makes sense, im not too good at explaining things sometimes
     
  3. sam the dnb man

    sam the dnb man Variation

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    The higher the curve the more resonance there will be at that frequency.
     
  4. padders

    padders Member

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    Yeah I thought it might be something to do with resonance . However the Q value on that band of the EQ shows flat on the analyser I thought i would only get resonance if it was above the line.
     
  5. louis g

    louis g New Member

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    It has nothing to do with the above, it is to do with a filter phenomenon called 'dispersion of power'.
     
    Last edited: Aug 15, 2011
  6. IV4

    IV4 Currently a newt.

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    'dispersion of power'
    Is that like a super team police unit in London?
     
  7. miszt

    miszt BASSFACE Royale

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    This can be a bit of a pain, you can use a dynamic/adaptive EQ like GlissEQ to have more control and avoid this problem
     
  8. tv_g

    tv_g Active Member

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    phase offsets near the filter band i reckon