Sorry, but the old farts are right about sound levels

Every sound engineer hears the occasional, annoying scolding from an older church member about excessive volume. It turns out that we should probably listen to them.

Like many of you, I love loud music. Filling the sanctuary with high volume, beautiful sound gets my worship juices flowing. And it goes without saying that the bass should pound you straight in the gut until you have to catch your breath. Like most of you, I've always felt that a little loud music never hurt anyone. Well, I was wrong.

A fews years ago, I saw an audiologist about chronic tinnitus and was shocked to find out that my hearing loss was permanent. I was never much of a concert-goer in my youth, but I did blast the tunes in my car a lot. Add in a few years at an auto service shop listening to loud engines and power tools, years of Saturdays in the yard with lawnmowers, leaf-blowers, and chainsaws, a few trips to the local dragway, and you have a recipe for permanent hearing loss. The problem is, you don't find out until later in life.

Noise-induced hearing loss is an insidious problem, sneaking up on you and secretly stealing precious decibels before you even suspect their absence. With a few exceptions (like a close-proximity explosion), most damage caused by short term exposure to loud noise is repaired by your body. Sustained exposure, however, can permanently kill cells in the hairs of your inner ear, a little bit at a time. At first, the loss is imperceptible, but 20 or 30 years later the cumulative damage will have you leaning in to hear people in normal conversation.

The definition of "sustained exposure" is, unfortunately, much shorter than you think. The CDC states that permanent hearing damage can occur after 2 hours of sustained exposure at 90 db - the level of a typical leaf blower or lawn mower. Bump that up to 100db (the level at a typical professional sporting event), and the safety threshold goes down to 15 minutes. Planning to attend a rock concert (about 110db on average)? You have 2 minutes before the cells in your hearing-hairs start passing away...forever.

The good news is that most churches can stay below 90db on average with a good mix and proper speaker placement. An untrained sound technician, however, can often make the mistake of turning certain channels up too far rather than using dynamics, EQ, and effects to make space for them in a mix. I've also found that venues with poor acoustic design generally require higher volume for voice intelligibility, which tends to drive up the overall mix volume.

From an acoustic design perspective, I recommend spreading out your sound stage as far as possible. In other words, whenever possible, use more speakers playing at lower volume in close proximity to your congregation rather than fewer speakers blasting at higher volume to reach all the corners of a room. This is how Disney does it. You will notice in Disney parks that performances are always easy to hear but rarely reach anything close to dangerous levels.

Focusing on the quality of your sound isn't just an aesthetic consideration - it's a health imperative. So the next time that old curmudgeon comes back to the media booth with a complaint, be prepared to show them how you are keeping the decibels at a safe level. Here's a good infographic published by the CDC on this topic:

End of public service announcement. :)