1/3 Octave EQ vs Parametric EQ

[coolhandjjl]

What is the difference between a 1/3 Octave EQ and a Parametric EQ? Does a Parametric let one 'hone in' to specific frequencies more precisely rather than settling for the pre-set 1/3 octave increments in the former?

[Bruce Weldy]

The 1/3 octave has set frequencies and fixed bandwidth for each selected frequency. The parametric will let you select not only the frequency that you want to cut/boost, but also allows you to define how wide/narrow the bandwidth around the frequency that you selected is. So, by narrowing the bandwidth you can affect just the frequency that you select with out affecting the frequencies all around it.

Hope that helps.

[Fish]

1/3-octave graphic EQs may have controls centered on 1/3 octave frequencies, but they often affect a full octave-wide swath of the spectrum—sometimes more. Not very surgical, especially for tuning monitors! A fully-parametric EQ allows you dial in whatever width you need (really narrow or really wide, and anywhere in between), at ANY frequency along the spectrum, for each available band of adjustment. If you need to adjust something in between two bands on a 1/3-octave EQ, what happens when you pull down both faders depends entirely on the specific model in front of you: most just give you two dips at the specified frequencies, some (like Rane's older analog graphics) combine and give you a bigger dip in between the two frequency points, and some (like the newer Rane DEQ-60) give you a response that effectively matches fader position to response curve.

I personally have come to prefer paramtrics over graphics every day of the week. Make a boost or cut, fairly narrow, and sweep along until I find the exact spot I need to tweak. Adjust gain to an appropriate level, play with the width until it's good (generally: wider for tone shaping, narrow for feedback removal), and walk away. No playing with multiple sliders, and no being stuck with cutting out too much or too little depending on the need.

[WB]

Does a Parametric let one 'hone in' to specific frequencies more precisely rather than settling for the pre-set 1/3 octave increments in the former?

Yes. Some units will let you dial in as small as 1/10 octave band, or as wide as 10 octaves. I consider the two types of EQ as two completely different tools for different jobs.

[jeffsco]

I prefer Parametric for Room Equalization (I know we're not supposed to use that term... ), Speaker compensation etc. and use the the Graphic for Feedback control. I use SAC as my mixing system so I have the luxury of using either. Using a parametric allows me to cover a wider frequency range with 1 control. Coupled with an RTA,SMAART or some other mesurement system...you can dial in a room using far fewer bands of EQ than with a graphic.