Basics of Parametric EQ

Max Output Level: -90 dBFS
  • Total Posts : 6
  • Joined: 2009/01/23 22:35:32
  • Status: offline
2009/01/26 19:37:43 (permalink)

Basics of Parametric EQ

Can someone explain to me the basics of Parametric EQ--e.g. what's low shelf, peak, high shelf, each of the four bands, the gain, the center frequency, and the quality knob?

6 Replies Related Threads

    Max Output Level: -77 dBFS
    • Total Posts : 668
    • Joined: 2007/10/04 11:04:23
    • Status: offline
    RE: Basics of Parametric EQ 2009/01/26 21:44:40 (permalink)
    Good question, I'd like to know about this more, too.
    Max Output Level: -44.5 dBFS
    • Total Posts : 3069
    • Joined: 2004/07/07 11:47:11
    • Status: offline
    RE: Basics of Parametric EQ 2009/01/26 22:24:21 (permalink)
    peak - boosts or cuts the center frequency.

    shelf - boosts or cuts the frequencies above (for a high shelf) or below (for a low shelf) the center frequency.

    high/low pass - completely rolls off frequencies above (for a low-pass) or below (for a high-pass) the center frequency.

    depending on the EQ you may not have a high/low pass. some EQs have set types at each band, for example: low shelf, peak, peak, high shelf. this is because those would be the most common setup for EQing a single instrument.

    some EQ's like sonitus allow you to do anything you want with each band. but all the band really is, is a center frequency. i.e., you want to boost the bass guitar line, so you use one band at 400hz (400hz being the center frequency) and you add 2dB of gain to make it louder.

    the "quality" knob or Q is it is generally referred to, determines how "wide" the band is going to be. for example, with a peak EQ, a Q of 1.4 is about one octave (if i remember right) and a Q of 0.7 is two octaves, although it's not on a scale that easily translates. generally for "fixing" things a narrower EQ is better (2.0 or higher), a Q of 1.0-1.4 or so is good for adjusting specific tonalities of an instrument, and 0.7 is good for subtle changes. none of this is set in stone, you have to hear it, these are just starting points that may or may not work at all.

    for shelf and low/high-pass EQs, the Q determines how sharply the curve will be set. a Q above 1.4 will actually start to boost or cut the center frequency in the opposite direction of the applied gain (so for a low/high pass, it will boost since those types of EQ always cut). if you want a sharper rolloff without the boost, combine a shelf with a high/low-pass EQ.

    gain, as i said, is a function of how much louder or softer you want this particular frequency (or range of frequencies, in the case of a shelf) to be. gain has no effect on high/low-pass EQ, which always cut down to silence.

    the best thing you can do to learn what an EQ does is to make big changes and start training your ear to hear smaller and smaller changes. also you should check out Voxengo's SPAN plugin, which when you hold down the ctrl key will act like a big boost for whatever frequency and you can sweep it around to hear the different tonalities of instruments at specific frequencies, and hear the way ranges of frequencies sound in general.

    hope that helps.

    - jack the ex-cynic
    Max Output Level: -52.5 dBFS
    • Total Posts : 2271
    • Joined: 2006/10/12 00:14:20
    • Status: offline
    RE: Basics of Parametric EQ 2009/01/27 01:32:08 (permalink)

    This is fundamental stuff, so for you...

    School days!

    Try this to start

    Lots of tutorials here. There's plenty of other sites where information is available, also, but you have to know some of the terms before you can search with Google. That's why I recommend Tweakheadz as a starting point.

    Also, subscribe to one of the consumer publications like EM or SoS. They have articles on this kind of stuff every issue, and they'll have things for your continued interest (and learning) for years to come, so when you find one you like, get yourself a two year sub and save a little money. But, first wait and see if you like this kind of stuff -- it's not for everyone. Some people just want to play music and not fuss with dials.

    Links below:



    P.S. -- Use the Forum Search (look to the upper-right, Search is in there next to FAQ and Member List), and search in here for a long post on EQ from a user named Yep, from maybe two or three years back. Yep wrote a few long tutorials on key subjects and left them here for users just like you, so when you've digested EQ, move on to the other key topic in Mixing known as Dynamics and Compression. They're pretty well done so check them out.

    post edited by kwgm - 2009/01/27 01:38:39

    Max Output Level: -44.5 dBFS
    • Total Posts : 3069
    • Joined: 2004/07/07 11:47:11
    • Status: offline
    RE: Basics of Parametric EQ 2009/01/27 17:57:48 (permalink)
    also look for posts by "chaz" with "mixing" and "EQ". there was a thread that went on at length about EQ but it's slipped i'm afraid. should have been made into a sticky.

    - jack the ex-cynic
    Max Output Level: -90 dBFS
    • Total Posts : 6
    • Joined: 2009/01/23 22:35:32
    • Status: offline
    RE: Basics of Parametric EQ 2009/01/27 20:05:50 (permalink)
    All right, sweet. Thanks for all the resources... I'm sure this will keep me occupied for a while.
    Max Output Level: -53.5 dBFS
    • Total Posts : 2193
    • Joined: 2008/12/16 06:57:38
    • Status: offline
    RE: Basics of Parametric EQ 2009/01/29 09:53:36 (permalink)

    one thing that might help in understanding "parametric"
    eq is and equal mix of using it and reading about it in the
    begining. turn the knobs and try to notice "what you here"

    of course "take it easy" speakers can only take so much
    so be gentle.

    without having one its a little hard to grasp the concept in full.
    do you have one? in a way there is no such thing as a "tone"
    control. they are only volume controls set to a given range
    and raise or lower the "volume" in "that" range.

    Q doesnt mean quality it means width. parametric eqs can
    create problems sometimes too if a person is "overlaping"
    bands. if you can find some visual pictures of this kind of
    of stuff that would really help too.
    Jump to:
    © 2018 APG vNext Commercial Version 5.1