EQ Characteristics

  • Thread starter Thread starter Blue Bear Sound
  • Start date Start date
Blue Bear Sound

Blue Bear Sound

New member
Found this on RAP and found it clear and concise - thought I'd share!

Bruce

This is a repost of a post Mixerman made back in Nov in response to a question about eq on R.A.P. (rec.audio.pro)

It can be hard to put into words some of the more abstract characteristics of why we do what we do when shaping the tone of multiple sounds into something that resembles music. What follows is a very practical way of thinking about how to use eq effectively.

Thanks Mixerman for taking the time to put into words what many of us have learned by trial and error, instinct, and hours upon hours of turning knobs up and down.

30hz super duper low, often referred to as subs up to 60hz These are dangerous frequencies to be playing with.

50hz super low

100hz pretty low and beefy, easily replicated in a 6" speaker

250hz the start of the lower mid range, woofy, not a clean low end, sometimes to much of 250 is too thick. However, it is the range of bass that will replicate well in a 2"-4" speaker, so you don't want to eradicate it.

500hz lower mid range, often accused of sounding boxy.

750hz getting towards the upper end of lower mids. Also slightly boxy, tends to reduce clarity, however, it can also add presence in the right situation.

1000hz or 1K this is the beginning of
the upper mid range, it is a very present frequency as it is so close to the peak of hearing.

2k (2000hz) This is our most easily heard frequency as humans. Too much of this and harsh will be an adjective you'll hear allot. It is the end of the presence frequencies. 2K has been accused of adding bite.

3k (3000hz) Much like 2k, it adds bite. In my opinion it can be even more harsh than 2k.

6k (6000hz) Now we leave the bite aspect, and we're into dentist drill territory. This frequency can give you a nasty headache quick.

8k (8000hz) Now we are leaving the mid range territory, and entering high end territory. This is the most present high end frequency. It can be useful for brightening, without adding high end noise.

10k (10,000hz) Now we're really into high end. This is on the lower end of high end. The addition of this can be helpful in opening up a sound, and reducing he coloration of a microphone, or processing.

15k (15,000hz) This is very high end. It will often add artifacts as quickly as it will open up a sound. When adding high end, it is recommended to try adding 10k,12k, and 15k and decide which helps the most. When you're 60, you probably won't hear this very well anymore. Or, maybe you'll hear it all the time.

20K Don't fuck with this. It's way too high.

EQ's boost and cut more than just the frequency that is selected. You can usually adjust the amount of frequencies you are affecting with the boost and cut by the "Q". The "Q" adjusts the amount of frequencies that you are adjusting with your boost or cut. The selected frequency will get the majority of the boost, and will be in the middle of all the frequencies affected. This is called a bell curve.

The boost and cut are usually in db increments. A typical EQ can boost or cut in the range of 12db. A great way of learning exactly what characteristics a frequency has, is to boost between 8 and 12db and sweep the frequency until you find a very offensive frequency. Then cut that frequency to taste. After a while, you'll figure out what the characteristics are of certain frequencies from this method.

I hope this helps.

Mixerman
Click to expand...
 
Bruce, thanks alot for that....Im just starting to get where I can hear frequencies and recognize them somewhat....Over at ArtistPro there is an mp3 soundclip and they are going band by band boosting and cutting and telling you which band it is....I found hearing what the frequency sounded like was better than giving it a name like "boxy" or "harsh"....Definitely helps you see where the sounds live....

I think that should be everyones lesson for today....pull up a mix and a parametic eq, with a 12 db boost, and sweep from 30hz or so to 20khz or so, stopping along the way to "hear" the frequencies......definite eye opener....
 
Good one, Bruce. Really helpful.

Hey, you two - when sweeping EQ-style, what kind of Q do you use? Very narrow? Moderate? Broad?
 
The answer is "it depends..."

...in general, when I have to EQ, I home-in on the area I want affect using a moderate Q setting, and once I found it and make changes, I adjust the Q to the narrowest position I can that still gives me the desired result... (in hopes of minimizing the impact on surrounding frequencies of the signal)

Bruce
 
Bruce,
Can you post a link to the RAP site? I've done a few searches on the net but I don't think that any of the stuff I've found is the site your talking about.

Thanx
 
Great Bruce! 1 of the least understood topics is EQ freq ranges and the chart you provided helps 1 to understand.
 
Good one, Bruce.

Getting back to Dobro's issue, which I think is an important one, I've found that the narrowist band that seems to accomplish anything is usually about 0.5.
Also, I'm talking about a software EQ; do you think that the bandwidth parameters are likely to differ between a software digital eq and an analog eq device?

One other thing, Sonusman once suggested that any boost or cut greater than 6db in a software eq is not going to work well. But another engineer I know told me that you need to turn up (or down) the software eq settings much more than you would to get a comparable effect to an analog.

What do you think?
 
Level adjustment increments on hardware faders are fairly intuitive and to a a degree consistent (since the manipulation is physical), but in s/w, the increments can vary and there is no physical sensation capable of being modelled, so it is quite possible that s/w adjustments will be different than h/w adjustments.

As far as a general 6db rule - there's no "standard", I think what Ed was getting at was that if you find yourself having to use more than 6 db changes using EQ, you may be looking at a badly recorded track that you should consider re-cutting and re-recording, if possible.

There are 2 extreme schools of thought regarding EQ:
1) Record the track the way you want it to sound using proper mic and placement. Since I got it right during tracking, why the hell would I need to adjust EQ at all on mixdown...... you can take those knobs off the console for all I care!!!!
2) Record the track the way you want it to sound using proper mic and placement. Adjust EQ any way you bloody well please, during recording or tracking -- don't bother me with your minimalist bullshit, I do what I likes!!!!

Personally, I fall somewhere between the 2 extremes - I record the track the way I want it to sound, avoiding EQ unless needed. On mixdown, only to shape a track to work within the mix, if needed.

Naturally, if I didn't track the project to begin with, all bets are off - most of the time, I have to fix up major tracking issues - EQ gets used pretty extensively in that case!

Bruce
:)
 
AWESOME Post bruce and thanks.

What do you think about 30 hz. I created a sine wave in soundforge at 30 hz, and even on my ten inch woofers, it still sounded very indistinguishable. like it would just muddy up a mix

40 hz was awesome though.

Another thing I noticed from looking at eq graphs is that some songs have 15 k added. Even when I can't hear the effect, I can still see the 15 k going. Is there any reason for this?
 
This might go in here, if not spank me. Some months ago I stumbled across a very nice website with good recording tips, specifically on the subject of EQ (stuff about how to make a list of words connected with frequencies, ie 500hz = "punch" or whatever :-). In the meantime I have lost all bookmarks (nooooo). The site was recently redesigned, when I visited and I think there was something with the word "blue" in the url or the site name. Could the site be german (althouhg in english)? I also think it used to be a place for guitarplayers, but now offered advice to all recording-geeks. Any info will make me smile.
 
You must log in or register to reply here.
Back
Top