You’re too old? You’re too close to the speakers? You’re too picky?? I see a lot of churches that have SPL limits for their services. In the touring world, we call this a speed limit. What is safe? What is too loud? What do the numbers mean? There are so many factors to consider before enforcing a speed limit at your church.

The most common complaint any audio engineer hears is, “It’s too loud.” When I hear that, I don’t reach for the master fader, I start asking questions. How close are you to the stage? Why is it too loud? It’s amazing that some people will try to meet a friend at a show, stand up close to the stage, then say it’s too loud because they can’t have a conversation while a rock band plays 20 feet in front of them.

In a church setting though, “It’s too loud” usually always means the exact same thing…

Typically, the volume complaint comes from the fact that the person doesn’t like your mix. It’s the honest truth. The common church attender doesn’t know to tell you, “Can you reduce 3kHz on that electric guitar, because it sounds pretty harsh and I think a smoother sound would be easier to listen to.” They just know that if you turn it down, it will be less abrasive to them.

This was recently demonstrated when I helped out at a church who always tried to keep the audio at 95dB or under. We zero-ed the board and started checking each input from scratch. The end result was a much smoother mix and was very pleasant to listen to. During the praise and worship, one of the more volume-aware pastors walked by the booth and was asked what he thought of the sound. His response was, “It could be a little louder.” The meter was reading 97dB.

Another big factor in measuring SPL is where you are measuring. Are you walking around? How close or far from the stage are you? Every time you add 10dB, your volume is about doubled. If you are measuring at a distance of X from your speakers, then at a distance of 2X, your volume will be about half. All of this is to help you understand the factors involved in measuring spl, not just me telling you where to stand and what number to look for.

One last factor to consider is that of “A” weighted and “C” weighted measuring. Simplified, C-weighted measurements will sample the SPL of all frequencies. A-weighted measurements, however, ignore the lower end of the spectrum. As frequencies get lower, it becomes more difficult to tell if you are hearing the audio, or feeling the air move (consider a kick drum hit). A-weighted SPL will appear to be lower usually, because it is ignoring the low end.

Let me end with a story. There is (was?) a club in Dallas, TX that I visited several times over the last year touring. The club imposed a 95dB limit, but measured it from the very back of the room at the soundboard. It was loud, but not crushing. After soundchecking, I was always left alone to do my job mixing the band, but I would reach over and flip the meter from C weighted to A. Without fail, the house tech would stop by, look at the meter, see that I was under 95dB, and get a perplexed look on his face. I just smiled.

This blog entry was inspired by a recent Twitter post I made about being asked to turn the audio down at a rock and roll show. Please follow me on Twitter and I welcome your tweets, re-tweets, messages, and @replies!