Photo by zteamie

Photo by zteamie

Recently I had a chance to sit in on a seminar given by Kent Morris. Kent’s a brilliant guy. He works with Peavey and focuses on training churches on sound systems and how to use them. The topic of the seminar was how to use multiple microphones in a live situation.

Since this blog is about home studios, I won’t be getting into all the different topics he covered. Suffice it to say, Kent’s a brilliant presenter. If you ever get a chance to hear him speak, please do so.

What really captured my attention was something Kent said about EQ. He was talking about how to EQ a vocal to bring out clarity and definition when he made the following statement:

“Every instrument you deal with has a fundamental frequency in the 250-500 Hz range.”

The dictionary on my Mac defines fundamental frequency as “the lowest frequency produced by the oscillation of the whole of an object, as distinct from the harmonics of higher frequency.”

What does that mean? Let’s say I’m singing an A note. 440 Hz is the fundamental frequency of that note, but that’s not the only frequency present. The sound of my voice is made up of that fundamental frequency combined with a complex mixture of harmonics at higher frequencies. These higher frequencies are what we use to differentiate my voice from another voice singing the same note.

Or let’s say a piano and an acoustic guitar play the same note. The reason we can tell the difference is because the harmonic content of each instrument gives the instrument its timbre.

To review, the fundamental frequency defines the pitch, while the harmonic content defines the tone of a sound.

So what does Kent’s quote have to do with us? Well, when mixing a song, we’re combining a bunch of tracks. If the fundamental frequency for each of these tracks is somewhere between 250 Hz and 500 Hz, then we’re obviously going to have a huge build-up in that range.

This, ladies and gentlemen, is where the mud comes from. You know what I’m talking about. Each track you recorded sounds amazing when you solo it, but then when you bounce a mix of everything, it’s all muddy and cluttered, and it gives you a headache. (I’ve done mixes in the past that literally give me an instant headache…sigh.)

Dealing with the “mud range”

So how do we take this information and put it into practice? Here’s my advice: next time you’re mixing, and things are sounding muddy, don’t immediately reach for the high frequency EQ knob and turn it up. Instead, spend some times cutting out some of that low-mids.

It’s been said many times, but I’ll reiterate it here. EQ is meant to be a corrective tool more than it’s meant to be an effect. Removing problem frequencies (doing an EQ cut) is almost always more effective than boosting other frequencies.

The easiest way to do this is to take one of your EQ bands in the low-mid area and do a big boost. Next, sweep the frequency up and down until you find where the “mud” is coming from. (I have a sneaky suspicion it’ll be between 250 and 500 Hz.) Once you find the frequency, turn the gain down until you’ve done about a 3 dB cut and take a listen.

Oftentimes a 3 dB cut is all it takes to clear things up. Use more or less as you see fit, and hopefully there will be much less mud in your future.

How do you handle EQ? Leave a comment.

  • Kenneth Dotsey

    I stream music from radio stations through my computer there is no way to control the sound what they send is what you get and most times it is loaded with bass frequencies and sounds very muddy looking for a solution to that

  • Jeff Monson

    If the tracks sound awesome when soloed and you’re EQing one at a time, how do you know where the mud is? Should you be EQing a track while it’s being played back in context?

    • Dimitri

      Always EQ in context. You may solo from time to time, mostly to scope out a desirable frequency, then apply EQ in context to the mix. Making instruments sound good on there own is contrary to the point of mixing. Mixing is supposed to make instruments sound good together rather than one on its own.

      • Ditto.

        • Mike Galvan

          What are some good tips for EQing in context with everything playing? I tend to have a difficult time hearing it when everything is playing, and if there’s a lot of mud to fix. What’s a good starting point?

          • Try finding the muddiest track and fixing it, then move on to the next-muddiest track, etc.

            • Evil Liberal

              I have a hard time actually hearing the “mud” in a bass track. Sad to say 🙂 Since we usually mic the bass when I sweep on a narrow band I find the other sounds you don’t want. We decided to switch to a DI bass and I’m dialing that in now.

  • Despite some beliefs, low end instruments like the trombone, tuba and timpani have fundamental frequencies below 100Hz.

  • dontouch

    Having an accurate room is more important than anything else, or is it an over-statement? My mix always sounds good on the monitors, but different in the car, even worse on laptop speakers. Often times the bass is either too much or not enough. So it takes quite a lot of back and forth to get it right…You listen to the song 50 times in two hours. At the end you can’t tell anymore… So frustrating.

    • An accurate room is always good, but none of us will have completely accurate rooms. There will always be bass issues in small-ish rooms. The key is to do what you’re doing, and you’ll learn over time how your mix NEEDS to sound in your room so that it sounds good in other rooms, too.

      Listening to good music in your studio is a big way to learn what your speakers sound like when a good mix is played through them.

      • Nobody

        Time does nothing to improve knowledge or skill in mixing. The room does play an important role. I acoustically treated my studio with help from a professional and mixed sitting in the sweet spot with high end monitors.
        A year later I began contemplating suicide because everybody else who chose to do music is making great powerful clear mixes and I cannot seem to, having spent 15 YEARS reading, testing, trying, learning, reading, testing, writing, listening, etc.
        Time does nothing. Experience does nothing. You either can or cannot make a clear mix.
        Every time I read an article like this, or watch a YouTube tutorial where a kid effortlessly makes a clear punchy mix… it only encourages me to try again.
        But I should know by now I will never make because I cant.
        There is no science to it.
        I hope I get killed today.

    • Jasonsharke

      Don’t forget to do a little checking on headphones as well. You can often identify problem frequencies very easily like this. Use a plugin like the Redline Monitor to reduce some of the problems associated with mixing on headphones.

    • Donny T

      Reference your mix through a cheap bluetooth speaker to “emulate” your jam being played through a phone, smaller speakers etc.

  • LRH

    Does anyone have a chart thats tells the frequencies of the Sub, LOW, MID, HIghs? I have a little challenge in knowing which frequencies is what.  I’m really practicing this method as I’m gaining progress,….thats everyone

    • I don’t think a chart will really help. You just need to train your ears to know what the different frequencies sound like.

  • Anonymous

    cool stuff. i cut some frequensies near 300db almost at every instrument and this makes a difference.
    and on snare, overheads, bass, distorted guitars, i will scan hi frequencies to cut out some notches that brings unmusical sizzle

  • Anonymous

    cool stuff. i cut some frequensies near 300db almost at every instrument and this makes a difference.
    and on snare, overheads, bass, distorted guitars, i will scan hi frequencies to cut out some notches that brings unmusical sizzle

  • Adam

    Good description of where the mud lies. I came across an article once, that I should have clipped and saved, outlining the frequency ranges for different descriptors we use for sound. As “muddy” is 250-500, they had corresponding numbers for “tinny” and “boomy” and “chesty” and “nasal” etc… How would you define these and other common frequency areas?

  • jems

    Great article. This has been driving me bananas. I’ve gone through all the textbook steps trying to tighten things up but still no mixing joy! My question is would you look for the “mud” frequencies on each track and cut them, or would you apply an EQ to the master track and try and cut this frequency range for the whole track? Or both?

    • I almost never EQ the master fader. I’ll EQ the whole mix during MASTERING, but not mixing. Your best bet is to find the “mud” on various tracks in the session and deal with THEM.

      • jems

        Ok thanks. I was going to EQ first before doing anything else, even before volume and panning because I thought EQing might affect the volume of each track and also change the frequencies in it meaning that it might change how I pan it, if at all and the overall volume I assign to it.

      • Al

        Try Blue Cat’s FreqAnalyst. It’s a free plugin that works with both Windows & Mac (VST,DXi,RTAS), and is used to analyze and show a realtime graph, so you will find out where to start EQing.
        Use this plugin on every single track that is suspected to build up muddiness. Then use EQ to cut the certain frequencies.
        hope this helps =)

        Download link :
        Quick Youtube tutorial :

  • Shawn T

    ok so i know this is most likely a stupid question but when you are soloing the track and sweeping the boost to find the “mud” what do you hear that really jumps out and tells you “ah, there it is?”

    • I just listen for the frequency that seems to jump and and is much louder than any other frequencies. That’s usually (but not always) the frequency I need to cut.

  • joewhite101

    EQ can be the make all or break all of a track. I've learnt that many times, whether it be mixing a track at home, or live at a venue. I have found, like you have described Joe, is that cuts do help. I try to find a 'home' for each instrument in a certain frequency range. With say kick drum and bass guitar, I spend a lot of time locking them in together as I often find that one usually overshadows the other. Over the past 3-4 years of me working with audio, my eyes have been totally opened by experience and reading other peoples views on the subject.

  • yes indeed. learning how to EQ was a life changer for me. i also wish i would have known “then” what I know “now”. my very first project was just stinkin terrible. all those tracks are gone now and there is no way to go back and fix anything. i attempted EQ but i didn’t know what i was doing 8 years ago. luckily i have a better grip on it now and now my ears are happy with comes out of my speakers. really learn your frequency ranges. it will make all the difference.


    E.Q. drives me bananas! But I would like to get a better grasp on using it. I’d much rather get the sound from the mics and the pre’s. But sometimes you have to reach for the E.Q. I think this has a lot to do with many of my recordings turning out “lo-fi”. I’ve gotten better at using recording gear over the years. But I still have a hard time with E.Q. and Compressors(I’m finally starting to understand compressors a little bit better, though). I have nothing against Lo-Fi Recordings. Heck, some of my favorite music was recorded that way. But when you buy “Pro-Audio” gear, I figure that isn’t your goal! Your goal is “Pro-Audio”.