Ken

I’ve been writing a lot about EQ this past week – starting with a basic explanation of frequencies and equalization in Some Good Equalization and Frequency Basics. I’ve talked a little about how to use an equalizer effect (EQ for short) to improve your recordings by either removing or turning down unwanted frequencies, or boosting certain frequencies. Now we should pull back a bit and talk about the bigger picture. Why should you use EQ? Like a lot of tools in audio recording, once you learn about how cool an effect is, you start to feel like you have to use it all the time. But that is the road to audio hell. Before you use any tool, ask yourself why you’re doing it. Does your audio really need the effect? If not, it is better to not apply any treatment. It’s kind of like medication. Often we find ourselves just taking it out of habit even if we don’t need it anymore. But all things being equal, our bodies, like our audio, are probably better off clean and sober. Don’t get me wrong. I’m a big believer in better living through chemistry, and I love me some EQ and compression and reverb on my tracks too. Just make sure you’re doing it for the right reasons.
So that being said – what are the reasons for using EQ? Let’s review what an EQ is. It is basically a bunch of volume knobs, each targeting a small band of frequencies (this describes a graphic EQ type, as opposed to a parametric EQ where you “dial-in” the frequency and the bandwidth you want to turn up or down), whereas a master volume knob turns up or down ALL frequencies equally. This allows us to JUST boost or cut, say the frequencies around 6Khz. That’s usually where sibilance is located, so a reduction in that area can help reduce overly hot “SSS” sounds, for example. So you really should always ask yourself some questions before applying EQ. Graham Cochrane just wrote an article about this called “3 Questions I Always Ask When Using EQ.”  His questions are:
What Frequencies Are Not Adding to The Track?
What Frequencies Are Hurting The Track?
What Frequencies Make This Track Sound Great?
I think these are excellent questions to help guide yo in the responsible use of powerful effects.
See Graham’s explanation of these questions here:
http://therecordingrevolution.com/2012/12/21/3-questions-to-ask-when-using-eq/
 

You’ve heard it before. It’s a common effect on lead vocals in pop music and has been for many year. I’m referring to the effect that makes the vocal sound like it’s coming through a telephone line. In fact, when I think of this effect the first song that pops into my head is the song by ELO called, interestingly enough, Telephone Line. Other uses for the effect that are common include making the drums sound like they are being played over a phone line at the beginning of the song and then opening up the sound later in the song to the full thing.
The way this is achieved is by severely limiting the frequencies that are audible on the target track to a very narrow range in the “mids” – between about 400 Hz and 4 KHz. See the picture on the right. You can use an EQ for this, or you can use frequency filters like the one in the picture in Adobe Audition called an FFT filter. FFT stands for Fast Fourier Transform, which you can learn more about here – http://en.wikipedia.org/wiki/Fast_Fourier_transform. In the Adobe Audition FFT filter, the preset is called “OnHold 400–>4K,” the “on-hold” part being a reference to being on the phone.
In Reaper, you can just add the ReaEQ equalizer effect that comes with the program, and change bands 1 and 4 to high-pass and low-pass, respectively, in the Type drop-down menu. Then drag the band circles until #2 is at 400 Hz and #3 is at 4KHz. Easy-peesy-lemon-squeezy!
BTW,in yet another attempt to confuse you the term high-pass filter actually means that you are preventing the low frequencies (those to the left of the target frequency) from being heard and only allowing the frequencies that are higher than that to “pass” through the filter. So you’ll usually find a high-pass-filter set up in the low frequencies (in the Reaper pic, band #1 is a high-pass filter, but it is located on the left of the spectrum – the low part). And the opposite is true for a low-pass filter. So in reality you could call a high-pass filter a “low-cut filter” and a low-pass filter a “high-cut” filter. I always have to do a mental translation in my head anyway. Sheesh. But there you have it.
Now you know how to create that phone effect in your recordings.
By the way, if you want to learn more about Reaper recording software, check out our latest recording tutorial course The Newbies Guide To Audio Recording Awesomeness 2: Pro Recording With Reaper.

When a vocal recording sounds muffled, like the singer/speaker has a box over his/her head, that’s usually NOT what we want. So what do we do about muffled vocals? In other words, how do we improve voice clarity?
If we can prevent the sound of muffled vocals to begin with, that would be ideal. You can get that vocal clarity by making sure you record with a decent microphone in a decent space.
For example, one thing you should NOT do is record in a closet. People often use closets as make-shift vocal booths, but unless you really know what you’re doing, you’ll just end up making your voice sound “boxy” and muffled.

Use the right microphone?

This can be caused by a number of different things, such as not using the correct mic for the singer (yes, some mics that sound awesome on one person may not sound good on someone else).
Generally speaking, the best kind of microphone for recording clear sounding vocals is a large-diaphragm condenser microphone. One good example of an excellent large diaphragm condenser mic is an Audio-Technica AT2035. You can find my review of that mic here: Review of the Audio-Technica AT2035 Microphone.

The wrong mic

Sometimes, you get a muffled vocal sound by using a common live-performance mic like a Shure SM58. That is a great mic for live stuff, but usually not so great for recording.
Don’t record with effects
Do not apply effects while you are recording! Some people you plug the mic into a “channel strip” or other piece of hardware to apply effects (EQ, reverb, tube emulation, mic modeling, to name a few). Don’t do this, or you will be stuck with those effects in the recording. If you find that one or more of these recorded effects is causing the voice to sound muffled, then there isn’t much you can do.
If you want to apply effects to your vocals, do it AFTER you have the clean voice recorded so you can adjust after the fact.

What to do if the vocal is already recorded?

How can you improve vocal clarity in a vocal recording? When recorded vocals sound muffled, it’s usually because there is too much energy in the lower frequencies. For a really good quick lesson on what a frequency is, see our post: Good Equalization and Frequency Basics.
You can use a tool called EQ (short for equalization) to clean things up. Before we talk about how to do that though, take a look at the video below from the article I mentioned above:

Using EQ to improve voice clarity
Now that you know what I mean when I talk about frequencies, you’ll understand when I say that muffled vocals usually have too much bass and/or low-mid frequencies. So with an EQ effect (in Reaper, I just put the built-in ReaEQ onto the voice track), start by filtering out frequencies below 80Hz. You might even try 100Hz.
Next, reduce (turn down) frequencies in the range between 140Hz and 400Hz. Turn that down by about 3-5 dB to start. That should do the trick.
I don’t normally recommend adding (turning up the volume) energy anywhere on the EQ to fix a problem since that can cause more problems than it fixes. Reducing is regarded as being much more effective and usually does the trick. But if those reductions don’t get you the clarity you want, CAREFULLY experiment with increasing some of the higher frequencies.
Try a small boost (start with 3dB) those in the 1-3 KHz area first. Humans are particularly sensitive to sound in this frequency range, so a small bump can help clear up a voice.
Another range to try boosting is the 9-10 KHz area. This can add a bit of sparkle or air to a voice.
Let’s review
If your vocals sound muffled in your recordings, you can fix this by:

1. Preventing the muffled sound by recording without effects, in an open space (i.e. NOT a closet) with a good microphone, and
2. If the voice is already recorded, apply some EQ to the vocal track. Just reducing the low and low-mid frequencies should do the trick. But if not, try boosting just a touch in a few of the higher frequencies.