Reasons People Say “It’s Too Loud” – It’s All About Frequencies

Every technical volunteer in a church (whether they are running sound that day or not) has had it happen to them. Mrs. Simpson makes a beeline for you after the service with that determined look on her face, and you know what’s about to come out of her mouth even before she says it.
“It’s too loud!”
Of course, the person in line behind her says that they couldn’t hear the sermon, or the soloist, or — well you get the idea. How can it be too loud, yet people are still not able to hear things? It is a conundrum!
You’re So Sensitive!
Part of the challenge was initially mapped out by a couple of scientists in the 1930s named Harvey Fletcher and Wilden Munson. Even though the International Standards Organization (ISO) has updated their curves recently (look at the ISO 226:2003 and 2014 standards), Fletcher and Munson’s work has held up very well over the last 80 years. They mapped out their ideas in a series of graphs that summarize their research on equal loudness as it pertains to frequency distribution. This is what the current science on loudness curves looks like.
Figure 1: The sensitivity of the ear at different frequencies at different sound pressure levels.
If looking at the graph in figure 1 makes your eyes cross, don’t worry about it. We can make two major generalizations from their work on volume matching at different frequencies.
1 — Your hearing is the most sensitive from 2kHz–5kHz.
2 — The way you hear different frequencies changes as the source gets louder.
Masking
Another physical principle to be aware of is the concept of masking. Simply put, one loud source tends to make it harder to hear other sources. This effect has the most impact going from low to high, and it is easiest to observe in the octave immediately above the lower sound.
Think about it this way: a bass guitar has most of its energy in the frequency range of 80Hz–100Hz, while a snare drum has most of its energy in the 100Hz–250Hz range. Both of these sounds have overtones that continue into the octaves above those ranges, which is why we use equalization on instruments above those ranges. This means the bass guitar makes the snare harder to hear as we turn it up.
Masking reveals our natural tendency to turn up sounds that we are having a hard time hearing as we mix. Mixing in a worship environment is further complicated by the fact that most of the instruments that we commonly use, like acoustic guitars, keyboard pads, and vocals, are focused in the audio range between 300Hz and 1,500Hz, with the overtones impacting how those sources sound directly in the range between 2kHz and 5kHz, where our ears are the most sensitive.
It’s far too easy to get into an endless loop where we turn things up to be able to hear them better — and then we have to turn something else up to hear it. At some point, Mrs. Simpson, from her pew close to the speakers, might actually have a good point. You have also been listening to those PA speakers for a soundcheck and three services, so your ears have grown a little less sensitive to total output!
Application: Output vs. Intelligibility
So how do we apply these facts as we start to mix? Glad you asked! Do you record your multitrack services? I ask because it is an excellent training tool and can have a big impact on learning how to deal with these issues.
If you have multitrack recordings of your services, call up a service and pull up just an acoustic guitar and a main vocalist. Set the level of the guitar at a comfortable level in your space, and then bring up the vocal so it sits just louder in the mix, and look at where the faders are. Let that sound sink into your ears for a minute. Now turn the vocalist back down. Go to the equalizer on the acoustic guitar and use it to remove about 2dB-3dB at 800Hz. You will find that the guitar may lose a little bit of its warmth, but don’t worry about that since it is the only thing you are listening to.
Now bring up the fader on the vocal channel to a level where it rides just above the acoustic guitar without looking. Close your eyes and do it by ear. When you get it set, look at your faders. You will find that you did not have to bring the vocalist up as far as you did previously. If you can bypass just this single band of EQ on your guitar track, switch the EQ in and out. You will find that this change makes much more of an impact on your mix than the tonality of the guitar. It will sound like you are turning the vocalist up and down slightly.
Take a look at or print out this diagram (fig. 2) that shows which frequencies are critical to the way an instrument sounds.
Figure 2: Look at or print out all the pretty colors — I mean frequencies!
One of the things that should be immediately apparent is that every single one of these sources has something important going on in the 2kHz–5kHz range, where our ears are most sensitive. Even the bass guitar and kick drum have components of their sound that are impacted up there!
As more channels of audio are added, this particular section of the frequency range becomes more and more packed with spectral content, and it can quickly sound like your mix is too loud even if you are in the back with a meter that is only showing 86dB SPL. Keep in mind that if you walk from your mix position to the middle of the auditorium, that signal is now at 92dB, as explained in our speaker coverage article, and in the front row where Mrs. Simpson is sitting, it could be 98dB. This really could be too loud for her, particularly if you have too much going on in the midrange and upper midrange, where our hearing is most sensitive.
From a mixing perspective, you can apply the idea that we demonstrated with the vocal and acoustic guitar throughout the frequency range by creating “notches” in your mix with EQ to carve out space for individual instruments without being forced to make everything increasingly louder.
It’s All About That Bass
Start at the bottom of the frequency range. Pull a little bit of 60Hz out of the bass guitar and a little bit of 100Hz out of the kick drum to give these instruments some elbow room of their own. You may find that you don’t like how each of these instruments sounds in isolation with this EQ applied, but that is not the point. If you are spending a lot of time equalizing instruments outside of the mix, you are likely creating problems that you will have to solve later. Also keep in mind that the louder you raise the overall mix level, the more that you will hear of these instruments because of the way our hearing works.
Moving Up in the Mix
Another place where volume wars can start is between acoustic guitar and keyboard sounds. Because musicians onstage are focused on their own sound and performance, they are often not aware that they are both pounding away in the same basic frequency range. Since this is also the range where lots of vocal energy is, the range from 200Hz to 1,000Hz is where you could spend the rest of your life working on the EQ and never fix all your problems.
If you play a recording of your service for the keyboardist and the acoustic guitar player, they will generally both tell you that you don’t have enough of them in the mix. If you turn them both up, they drown out your vocalists, and you are right back where you started, turning everything up.
Try asking the keyboard player (who typically has an easier time changing their voicing) to play in a higher register so you can “feature their playing a bit more.” Putting a positive spin on this is more likely to get an affirmative response. Getting these instruments into different registers will clean up your midrange and allow the individual instruments to shine through without the constant request for more level.
Cut Don’t Boost
Finally, although you have heard this until you are sick of it, try to avoid boosting EQ frequencies, particularly in that sensitive 2kHz–5kHz range. If you add EQ in this range to try to get some clarity and do it on more than one channel, it quickly turns into an ice pick in your ear. It is far better to pull some 400Hz–800Hz out of the instruments that are interfering with your clarity to get the same effect.
Also, in case you didn’t know, increased distortion in your sound system will always be perceived as increased loudness, so if you’re pushing your mix into distortion, whether at your amps or speakers, then someone will likely complain that it’s too loud. If you want to talk through a sound system upgrade for your church, give your Sweetwater Sales Engineer a call at (800) 222-4700.
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