If you have been in church for very long, you have heard numerous complaints about the sound being too loud. However, it seems a small percentage of people are doing all the complaining.
How do we know if their complaint is legitimate? This question often leads to the purchase of an SPL meter.
What is an SPL meter?
SPL meters are also known as ‘sound level meters’. They measure the sound pressure level in decibels (dBs) and are primarily used in industrial spaces to help protect workers’ ears.
Wikipedia states: “…the reading from a sound level meter does not correlate well to human-perceived loudness…” and I could not agree more. But, before I explain why, let’s touch on frequency weighting.
What is frequency weighting on an SPL meter (A/C button)?
The human ear is more sensitive to frequencies between 500 Hz and 8 kHz and is less responsive to very low-pitch or high-pitch frequencies. However, in a louder environment (such as a modern church service), the human ear has a much flatter response, becoming more responsive to those very low-pitch and high-pitch frequencies.
Because of this, most SPL meters have two frequency weighting options: A & C.
A-weighting gives the very low-pitch and high-pitch frequencies less weight than the 500 Hz to 8kHz range. Like the human ear, it effectively cuts off the frequencies the average person cannot hear.
C-weighting has a much flatter response, just like the human ear does in louder environments. In situations such as a modern church service or concert, c-weighting should be used due to higher volumes and use of subwoofers to produce a higher volume of low frequency noise.
SPL meters may not be the most effective way to solve the ‘loudness’ problem.
The problem with using an SPL meter for a church service is that it only gives you an overview of what is going on in the room.
Using it to gauge how loud to run your mixer is like flying over your house in a helicopter to see if you need a new roof. Sure, you may be able to see a missing patch of shingles from up there, but you will not see the one cracked shingle that is actually causing the leak.
When someone complains that the music is too loud, it is generally one portion of the frequency range hurting their ears, not the entire mix. However, to fix the problem, most sound techs are instructed to turn the entire mix down. The result: a mix that lacks energy.
A Better Solution: Sound Frequency Analyzer
Instead of using an SPL meter, I recommend using a sound frequency analyzer, also known as a real-time analyzer (RTA). Specifically, I recommend the Octave RTA app.
This will enable you to find the exact frequency range causing your loudness problem. Then, you can simply use EQ to fix the problem without having to turn down the entire mix.
For example, when my church moved into our current facility, we had all kinds of sound problems. Microphones would easily feedback and achieving a good mix was impossible. By using the Octave RTA app, I found that 400 Hz and 800 Hz bounced around like wild in our room.
I am not sure why this happens, but I know that surfaces and room dimensions have a big part to play. Luckily, I was able to use an EQ to cut troublesome frequencies and provide a more even room response – setting the foundation for good sound.
For a step-by-step process on setting EQ with a RTA, see: How to Set EQ with iPhone Sound Frequency Analyzer
Finding the Happy Place
There is a happy place in church sound where there is plenty of energy but it is not overly loud. This is where I want to be every service. The room should not feel naked but should be full of sound.
Keep in mind, there are still those who will think this type of environment is too loud, but it is absolutely impossible to keep everyone happy, so don’t even try. Simply do your best to create an atmosphere conducive to worship.
You might also enjoy: How to EQ Your Room with the X32