Let’s start with something familiar…the radio. Your radio has an EQ. Early radios had treble and bass knobs. This enabled you to either increase or decrease the relative frequencies. Boosting bass would involve kick drum sounds, bass guitar sounds, even low bass singers. Decreasing the bass would reduce some of those signals. Increasing treble would increase sounds in the upper register – think flute, upper piano octaves, and the high soprano voices. The common vocal range is more of a “mid-range” control but when it comes to just bass/treble controls, your EQ’ing abilities are limited.
Radios evolved into complex equipment with all sorts of EQ controls, from the simple bass / treble / mid to the more complex controls with 10+ faders for specific frequencies. To the audiophile, the complexity was welcome. To the common person, it was just plain confusing. Thus came the presets.
Radio presets
The presets were the manufactures means of helping the common user set the EQ to match the type of music (sound) they like to hear. Thus, preset EQ frequency modifications existed for rap, metal, country, jazz, blues, rock, pop, classical, talk radio, etc. Many computer audio programs use these preset definitions.
Each type of sound style has it’s own unique EQ settings that best show off its range of sounds and emphasize what should be emphasized and reduce sounds that should be reduced.
Enter the sound console.
Sound mixer channels have three to four knobs for performing EQ. The three common knobs are high (treble), low (bass), and mid (mid-range).
- High frequencies are around 12 kHz …ninth octave F# if you want to play that note on a piano to hear exactly where that is. This control has a two octave range when set at 12kHz. Using this control, you can add crispness to instruments. You can also use it to eliminate the hissing S out of vocals – speech or song. Check your manual for the specific high frequency point. It might be 10 kHz instead of 12 kHz.
- Low frequencies are around 100 Hz. Once you drop below 20 Hz, sounds are not heard as much as they are felt. Low frequencies can cause low end rumble and negatively effect speech intelligibility. Therefore, when used on a channel for vocals – speech and song, cut the low end frequencies. But not all vocals…singers who are true bass singers will get really low when they sing. Again, two range octave and check your manual for the frequency control point.
- The mid-range frequencies are from usually 100Hz to 3kHz (3000Hz). This is the standard (typical) range of frequencies that we hear. The bass instrument frequencies can be as high as 240Hz so while defined as “bass” the range is still within the mid-range frequencies. The mid-range control, again, is about a two octave span.
But how do you cut/boost anything with the mid as it’s not really a high or low-end control and covers a large frequency range? You “move the middle” with a sweeping mid. You alter where the middle frequency boost falls and then use the mid to boost/cut within that range.
Follow these steps for a little fun and learning in your free time:
- Go into church sometime when no one else is in the sanctuary.
- Grab a CD filled with a few types of music standard to your church services. For focusing on vocal EQ’ing, use an acapella track.
- Play it through the sound system.
- Set each EQ knob at the baseline position. This is the straight up setting, it’s not like a volume level of zero.
- Adjust the high knob for a while. Listen to the changes in sound, whether harsh or subtle.
- Set back to baseline.
- Repeat 4-5 with the low and then the mid and the sweeping mid.
- Then just have fun with all the knobs and listen to what sounds good.
- Take note of what sounds bad.
I recently used this method rather impromptu when a worship team leader shared his confusion with the sound mixer. I sat him down in front of the mixer, popped in a CD and let him EQ it a bit.
Let’s get REALLY practical!
All musical instruments and vocals (alto, tenor, etc) have a known frequency range. When you know these ranges, it will help you when it comes to boosting and cutting the appropriate frequencies. From there, you can tweak even further. For example, not all guitars sound the same even though they have the same frequency range.
Don’t be afraid of using the EQ.
Practice with it and in time, the congregation will hear the difference…”wow, the service sounded really good today. Even the pastor’s voice sounded clearer. Did you do anything?“ Yes, yes you did.
I'm Chris Huff and I've been working successfully behind a mixer for the last twenty years. Since 2008, I've been helping other sound techs learn all about the art of church audio through behindthemixer.com.
Sound Systems: Design and Optimization, Second Edition: Modern Techniques and Tools for Sound System Design and Alignment
Mixing Audio: Concepts, Practices and Tools
9 Insightful Comments on "EQ 101 – High, Mid, Low, and Experimentation"
Hi Chris. I found the information on this page to be very helpful in understanding the basics on sound. I only recently went from being a member to being on the stage then behind the sound desk so at first i didn’t know what i was doing at all. We work with a soundcraft gb4 30 channel and I wanted to find out more on how well does the sound desk go with the Bose p.a system. Our building provides challeges of it’s own as well. If possible can you send me tips and tricks of t trade that nobody is ever told when it comes to mixing sound, especially about feedback. Blessings
i want to know more about mid, hi,bess,and treble please send me ore information about this things.
thank you! God bless you!!!
What’s your idea on this? Let’s say this person speaking into the mic has a pretty high frequency voice. How should I adjust the lower frequency and make him sound fuller? Is there any effects w/ reverb or EQ I can do?
I'd focus on the midrange and boost a bit from there. I'd also try cutting some of the high's a bit. That can take out any harshness. Only after getting a fuller, yet still natural sound, would I think add any mild eq – just to warm their voice a bit. My pastor has a slightly high voice and that's what has worked for me.
Thanks bro! So you would always want to go for the natural sound? Are there any reason why I might not want to add in a little bit of low eq?
there likely isn’t any low frequencies there to boost. if you have a sweepable low mid you can find a lower mid freq that may help warm up his voice a bit—add some fullness.
hi this post has helped me more and i know much more thank you and our EQ has to midrange frequencies do they have to be at the same range or they in what way do they hel the high and low
God bless u!!!!!!
Some mixing boards have more than one mid-range. That is to say instead of having high, low, and the mid-range with the sweeping knob, they offer two in the mid-range each with sweeping. But then the frequency ranges that are controlled are different. Check your manual if it's not clearly marked on the board. If you can't find the manual, google online for the make/model of the mixer and the manufacturer will likely have the manual available online.
I really want to gain some in-depth knowledge of EQ. Are there any good places to read up on it?