I have heard this question many times, and mainly from the older group of church leaders. For those who grew up without subwoofers, it seems like an unnecessary expense and way to much ‘noise’ for church. However, the younger generation knows that a ‘sub’ is absolutely necessary for quality sound, whether it be in church or in their car.
Subwoofers (or “Subs”) add a range of frequencies (120Hz and below) to the overall sound that is absolutely necessary if you desire a ‘full’ sound from your church sound system. Your main speakers may be producing these frequencies, but it is not near enough to compensate for the rest of the sound produced.
What is going on in this frequency range? Mostly the sound that you ‘feel’ more than you ‘hear’, which is mainly produced by the bass guitar and kick drum. Have you ever been to a concert where you could feel the kick drum in your chest? You may not want that much for your church service, but I can guarantee that adding a subwoofer to your sound system will add energy and depth to your worship band.
When my church was planted in 2008, our first sanctuary was about 2,000 square feet, which would be considered pretty small. In this space, we had no sub, but we did have JBL JRX125 Dual 15” cabinets for our mains. These did a fairly good job reproducing lower frequencies, but it was always lacking that ‘in your chest’ energy. The bass guitar always seemed too ‘in your face’ and was a bit painful to the ears.
In 2011, we moved into a new sanctuary, about 6,000 square feet, and purchased a new sound system that included a JBL728S Dual 18” Subwoofer. We feed this sub 3200 watts from a Crown XTi 4000. Going from no sub to this super-powered sub was probably the most exciting sound system purchase I have ever made. The energy that this speaker adds to worship is amazing.
I can remember the first service with the new sound system, as many of our ‘subwoofer virgins’ were holding their chest through the first few songs, wondering if their heart was beating quite a bit harder than normal. I admit, we were probably running it a bit too loud at first, but the people still loved it. You can't help but dance and move around with that much energy in the room, it is a very freeing experience!