July 20, 2009 by DJ Elroy
DJ Hero’s theory behind EQing
Ok, I seem to have gotten a few requests for a second installment to DJ Hero’s production tips, tricks, and advice. My first, “DJ Hero’s V-Theory of Production” seemed to go over pretty well, so I hope this second pearl of useful production and engineering wisdom provides you with more ammunition in the studio.
The topic this time is EQing, which is by far one of the most powerful tools any engineer has to creating a cohesive, clear, and punchy mix. Like the V-Theory, EQing is essential to making your song sounds rich, full, bright, and yet another slew of color words that mean… good.
A little history lesson behind the term “equalization”. It was original coined by the phone company somewhere around the time that the telephone was implemented as a household item. Signal equalization was used to compensate for long cable lengths with respect to where the copper wiring came from and how long it was by the time it came in to the home. The equalizer is nothing more than a series of filters designed to shape a sound, but let’s not get over technical. There are a few different types of equalizers: analog, digital, graphic, and parametric. While the argument behind which is better – analog or digital – will probably continue into the sunset, it’s pretty safe to say that today’s engineers opt for the parametric equalizer over a graphic equalizer any day of the week because of the massive amount of control and shaping ability it provides.
To get started I’ll refer back to the V-Theory simply to remind you of the space you’re working in, low end at the bottom, high end at the top and all the space in between that your sounds (hopefully) sit. EQing will maximize that space so you can achieve a much cleaner mixdown with the finite overhead and space you have. You only have so much room to work with, and you want to be able to pack that space with as much sound as possible, without making the whole song sound muddy, cluttered, or lack-luster. EQing is one way to help you.
First, the EQ can provide you the means of shaping frequencies by means of shelfing, notching, or sculpting. The shelf creates a wall type shape; if you’re looking at the EQ (graphically), essentially every frequency below (or above depending on if you’re using a low shelf or a high shelf), that “wall” will be cut away. That will cause the remaining frequencies to sound perceivably more noticeable. Note, those frequencies have not been turned up, the others have been eliminated. Notching allows the engineer to cut out certain frequencies in a sound, the notch’s width can be adjusted to be really narrow or quite vast, with the audible results being slight to great.
Sculpting is another term I use, but it’s less on the technical end because it’s just a more subtle version of shelfing or notching. As a simple example we can take three sound layers, one low, one mid, and one high. For sake of the example let’s assume that all three are relatively thick sounds given the range of frequencies they individually sit in, so much so that they each impede upon the adjacent frequency range. Individually all three sounds could very well sound terrific, but when placed together, can get lost or fight for the same space as the other sounds. Like the V-Theory, EQing can reduce that “fight” for space, and cause a sound to use less space. The EQ will help isolate the range the sound sit in. The easiest way to describe it would be that if the low end doesn’t need to ride in the higher end frequencies, then shave them off, if the high end doesn’t need to ride in the mid or low end ranges, then we shave them off, etc. Perhaps I mistakenly use the term “shave” however. My professional opinion is to never cut full frequency ranges, unless you plan on filling them. Cutting entire frequency ranges unnecessarily will leave your production sounding empty. Instead we reduce ranges only enough to create the room needed to allow the combating frequency ranges the ability to breathe. One reason to avoid cutting entire frequency ranges is because any reverb that may be on those sounds will sound empty, and cease to be an effect and become simply noise in the mix. As well stereo delays will feel a little lacking as well. Imagine you were an amazing swimmer, and suddenly you had no legs, even though you are amazingly fit, and well trained, you’re still not going to be able to take a gold in the next Olympics (lest of course they are the special Olympics, but let’s not go there). “Waste not, want not” is key, don’t get rid of anything if there is no need to.
When EQ’ing the various layers of your song always, always, always do it while each sound is in the mix, what may sound good or bad while the sound is isolated may not be effective EQing when the sounds all play together. Also, always, always, always REDUCE before you BOOST. Instead of boosting a specific frequency range, reduce the ranges around the one you naturally want to turn up, then simply turn the overall volume up to make up for the reduction in relative volume. Again that is my professional opinion and not a matter of fact, but you’ll find you save overhead and avoid frequency phasing (unless you’re experienced enough to use it to you advantage). A lot of vintage analog equalizers have some really wonderful voice phasing effects that occur when frequencies are boosted, and that’s a part of the argument between analog and digital. Rather than get into that argument, I’d prefer to try teach some techniques that are going to be helpful regardless the skill level. So like I said, reduce the frequencies around the frequency range you desire to be more pronounced, then increase the over all volume of the sound, that will create the same effect without any ill side effects as boosting a particular frequency range.
Some ideas to keep in the front of your head are: What is the sound’s function in the song? Is it a bassline designed to drive the song? If so, shaving the top end will save a lot of room for sounds that move and fill the up mid and high end ranges. The same applies to high ends frequencies. The high hats, typically rest mostly in the high end frequency ranges. That being the case, you’ll be able to reduce the low end quite a bit without over working and hence destroying the sound of the high hat. Keep in mind what I said earlier though, cutting too much will leave reverb on that high hat incapable of sounding rich and natural, so only take as much as needed. Mid range frequencies are a bit tougher to EQ, for the simple fact that no sound JUST sits in the middle, usually they over lap into the low and high ends of the spectrum. If you shave those off, that pad in the middle will be sitting a little awkward. Again why I stress taking off only as much as is needed. I’m sure you don’t have to reach too far into your brain to agree with me that the one range of frequencies that get destroyed in the club is the mid range. Large PA’s often fall short in that department for several reasons, one is because the room and the sound system haven’t been set to work with each other. Another is because mid range tends to sit between highs and lows, and for most producers it’s tough to isolate and effectively bring those sounds out in a complicated mix. I won’t speak for the simple music that doesn’t have much going on, but in a song that is rich and full of sound, the mid range is the toughest range of frequencies to make stand out as a separate entity while maintaining a cohesive bond between the highs and lows.
The trick while EQing is to make each sound as unique as possible in the mix, while not isolating it from the other sounds to the point where the song sounds like a it’s a series of Lego blocks stacked on top of each other, one blue, one red, and one yellow. Having the individual color is obviously awesome, but the transition should be smooth enough to keep the mix sounding rich and full. To keep on the Lego analogy, the transition between the blue and red block should give you purple, and the space between the red and yellow block should give you orange. The amount of each however is up to your ears and what works for your mix.
Two things to keep in mind, your speakers will allow you as good a job as their own frequency response, so don’t think your PC’s stock speakers are going to provide you the ability to EQ effectively, neither will your headphones, though top end studio monitors like the Ultrasone 750’s will provide you with a better shot at it then your Pioneer DJ headphones. I don’t recommend using headphones to EQ anything — 99% of headphones are not designed to provide sound to your ear like your ear is designed to hear sound. Case in point, headphones blast sound directly to the ear drum and by-pass the mechanics of your earlobe. The earlobe is designed to channel sound to your ear naturally (take a minute to feel the shape of your ear before you try to argue), all those natural curves made from skin, hair, and cartilage actually are designed and grow for a reason. The second thing to keep in mind is that transient frequencies will often seem dramatically different with stereo placement (such as described in my V-Theory). A sound could easily be heard as muddy or empty or centered in the mix, but when moved somewhere else can take on new characteristics, and visa versa so listen carefully.
Professional engineers with years of experience will all agree that EQing when your ears are fresh is to your advantage. If you’ve been working on the song all day and are just trying to get it done, you will fail. Take a break, if you can afford to leave it for a day, then do so, but if for some ODD reason time just isn’t on your side, step outside, make some tea, pet the dog, do anything but sit in front of your studio. Typical when I’ve gotten a song to that point where it’s time for that final mixdown where EQing becomes vital, I will get a good nights sleep, shower in the morning (my morning), have some coffee, relax a bit, feed the dog, then go down into the studio. At that point I’m rested, my ears are rested; I’m awake and ready to go. Be patient, listen carefully. Sometimes you may find it necessary to bring certain ranges to their extremes just to hear what the EQ is doing to them, perhaps as a means to give yourself a reference point. I will add though, avoiding the boosting side of that, and cut them first to provide a reference. Boosting frequency ranges to provide a reference point can be harsh, and take away from the fact that you’re supposed to be using rested ears.
In my next tips, trick, and techniques, am I going to fully cover the compressor/limiter. Between “DJ Hero’s V-Theory”, Equalization, and Compression/Limiting, I will have hopefully provided you the means to use the three most powerful tools in your engineering bag; the trifecta, if you will, of audio engineering. The compressor can reduce the amount of EQing needed, and the EQ can reduce the amount of compression needed. Stereo placement can be thrown in there as well. The main point of all three is to take away as little as possible while maintaining as much head room and sound clarity as possible. The result will be full, warm, bright, and punchy sounds that make up a wonderfully produced track regardless the style.
Also check out DJ Hero’s V-Theory of Production
Aka DJ Hero
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