• TalkBass has been independent since 1998. Add your voice.
    Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
    Join free Log in
    Want zero display ads or expanded classifieds tools? Compare plans.

Parametric EQ: Typical Freq. Trouble Spots?

Zooberwerx

Zooberwerx

Gold Supporting Member
Dec 21, 2002
23,311
28,097
68
Virginia Beach, VA
#1
I have a Rane Para EQ inserted in our mixer and looking for "starting points", those freq's which have traditionally proven to be troublesome (feedback, mud, boom, etc). I'm at a disadvantage as we have no soundman so pretty much limited to setting what balances I can before the first downbeat. I'm able to pull off a decent sweep with my Demeter HBP-1 and Sansamp RPM but the PA is new territory.

Please share your experiences!

Thanks

Riis
 
#3
The only real trouble spots for me are freqs below 60 hz. Those tend to interfere with the bass drum and create muddy mixes, and anything past 5-6k, but that's just a matter of taste more than a trouble spot.
 
#5
I've asked a few of my sound engineering buddies questions like this - the answer has alway been that there's too many variables to have a rule of thumb. Maybe for a set room with the same PA gear, but even then the response is different if the room is empty vs full.

I guess all you can do is boost the level & sweep until you get feedback or uber-boom, then cut that frequency.

c-
 
#7
Hit you in the chest type power in the subs lives around 60 Hz. No offense to the extended range types but there isn't a whole lot useful going on below 40 or 50 Hz.

If the whole mix sounds muddy try cutting at 100 Hz.

If the whole mix sounds shrill try cutting at 3.1k.

There is a pithy saying with regards to EQ that has a bit of truth to it: Boost to make something sound different, cut to make something sound better.
 
#8
projectMalamute said:
There is a pithy saying with regards to EQ that has a bit of truth to it: Boost to make something sound different, cut to make something sound better....
Click to expand...

...and isn't that the purpose of a para EQ? I agree 100%. I'm starting to see some repeating "themes" so to speak....mud @ 100 hz, boom @ 160-180, shrill @ 3.1-4.2 khz.

Here's another observation: on occasion, I can discern a subtle "ring" which trails the vocals. Its not quite feedback but I would like to get it under control.

Riis
 
#9
Try looking at 4k. Seems to be a trouble spot with our guitarist, who absolutely has to have small underpowered monitors ripping his head off to the point of feedback. Sings great, but man, is he high maintenance!

Also, one thing that will greatly help you to understand EQ is to record instruments into your computer, get yourself a 31 band EQ plugin and a set of good headphones, and just go up and down the sliders boosting and cutting and listening to what gets affected.
 
#10
Zooberwerx said:
I have the 50 and 40 hz filters engaged on the power amp and crossover, respectively. The Rane allows #1 and #5 bands to be used for shelving although I'm not exactly sure what "shelving" is.

Riis
Click to expand...

I just finished struggling to make ASCII art to explain the concept for a while there and gave up. Wikipedia to the rescue:

The frequency response of couple of typical peaking filters looks like this

That's what the bands of the EQ are normally doing. The highest and lowest bands can be set to shelving if you want frequency responses that look like this

In each picture the red line and the blue line are two different examples of each type of filter.
 
#11
A simple way of explaining shelving is that it affects everything above (for the high) or below (for the low) the nominal frequency point. So e.g. turning down a narrow-bandwidth parametric EQ band centered at 100 Hz would scoop out a bell around 100 Hz, but at the lower end of the bell the levels would approach normal and from (say around) 70 Hz and down there would be no cut. Whereas with a shelving EQ centered on 100 Hz, turning it down cuts everything below 100 Hz (with a half-bell shape at 100 Hz).
 
#14
bongomania said:
A simple way of explaining shelving is that it affects everything above (for the high) or below (for the low) the nominal frequency point. So e.g. turning down a narrow-bandwidth parametric EQ band centered at 100 Hz would scoop out a bell around 100 Hz, but at the lower end of the bell the levels would approach normal and from (say around) 70 Hz and down there would be no cut. Whereas with a shelving EQ centered on 100 Hz, turning it down cuts everything below 100 Hz (with a half-bell shape at 100 Hz).
Click to expand...

Not sure which definition applies, but here's the spec. sheet link: [Invalid or Expired Link Removed]

Riis
 
#17
Most PAs (with subs) have a nasty bump around 80.

Most Bass rigs have a bump around 160.

When used at 0" distance, most vocal mics are up about 10dB at around 200 (and it's a very wide bump).

There's often a "honk" somewhere between 400 and 1k.

Host PA horns have a nasty resonance about 4k or 7k.

Most vocal mics have a peak somewhere between 2k and 8k.
 

Latest posts

Top Bottom
Back