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This is the full
length version of the article published in the June 2003 (premier)
issue of Religious
Product News magazine. The web version posted on their site
had been edited by their editors to fit in the space allotted;
the print version of the magazine had been edited once again and
eliminated a few other key sections.
Part 1
One could write a lengthy book on the subject of speakers, and
another on amplifiers—no need to do so, however, it’s
already been done more than once! I find many people in the church
community don’t know the basics when it comes to what it
takes to determine the proper speaker or amplifier for their church
sanctuary. While there are many variables to consider, I’d
like to cover a few basic issues that require consideration. Here’s
a few points to keep in mind throughout your reading of this article.
- The acoustics of the room determines how well any audio
reinforcement system can work
- Speaker location determines if the system is great or just
mediocre.
- Speaker choice shouldn’t be made based on brand name
or what everyone else uses.
- Amplifier choice is nearly as important to the system as
the speaker choice and location in achieving a great system.
Acoustics First
First of all, you can’t choose a speaker or speaker system
for your sanctuary unless you have an intimate knowledge of the
condition of the acoustical environment. That is to say, the acoustics
of the room determines how well any speaker will perform in the
room. Put a great speaker in a great room, and you have great
results. Put a great speaker in a poor room, and you have poor
results. It can’t be stressed enough that the acoustics
of the room places limits on how good the speaker system will
perform and how good it’ll sound. Of course, the acoustical
condition of the room also determines how well the choir will
sound, how well the piano and organ will sound, how well the congregation
sings, and how well people understand the minister.
There are thousands of different speakers made for live sound
use. Of these, only a portion should ever be considered for use
in a church. If the acoustics are good, you can choose from many
of the available models. If the acoustics are poor, you’re
limited to selecting from a very small group of speakers that
often cost quite a bit.
The argument is, you either spend a ton of money on expensive
speakers that will work in a poor acoustical environment, or spend
much less money on the speakers and fix the acoustical problems.
If you go the route of the expensive speakers and leaving the
room bad, then the only time people will be able to hear properly
is when the audio system is used (assuming the system was designed
and installed correctly). This means that smaller events held
in the sanctuary that don’t need any audio reinforcement
will have to continue suffering with the poor sound in the room.
This would apply to small weddings and funerals, kids’ choir
rehearsals, youth choir rehearsals, adult choir rehearsals, drama
rehearsals, praise band and soloist rehearsals and even organ
and piano rehearsals or recitals. Putting in the very expensive
audio system can help only the times when it’s being used.
It does nothing to address the fundamental problem – the
room itself.
The other option is to fix the room. Just the other day I heard
from my associate Joseph De Buglio of another church who had called
to tell him of their joy with the acoustical work they did per
his recommendations. They told him the sound system was terrific
sounding and had a lot of gain before feedback they had never
had before. Thing is, they were talking about the OLD sound system,
the one they were in the process of totally upgrading! The only
complaint they had was that since they were now able to really
turn up the gain on some of the mics, they heard a radio station
in the system. Well, the radio station had always been there,
they had just never been able to run the gain as high as they
could now. In other instances, improving the acoustics of a sanctuary
results in the congregation thinking a new organ and sound system
had been installed.
Taking the time to understand the acoustical situation in your
sanctuary and addressing it correctly goes a long way in ensuring
every sound event will be heard the way it should be. This means
rehearsals go quicker because there’s no “could you
repeat that?” or problems with timing. The pianist and organist
can play together better, the drummer can beat as hard as he or
she wants yet it won’t be overwhelming in the room. The
minister can take 3 steps back from the pulpit, talk in a normal
voice, and everyone in the congregation will be able to hear him
because the acoustics are so good, the audio system can work the
way it was designed to. Those with hearing loss will again be
able to hear and understand what’s said because the noise
and interference from the poor acoustical situation has been remedied.
And finally, when the finance committee chairperson pleads with
the congregation to help raise funds for a special project, people
won’t bring in jar after jar of honey!
Speaker Placement
If you don’t have this little detail correct, you won’t
have a good system no matter what you paid for the equipment or
how good it looks. If the speakers are in the wrong location,
it makes the rest of the system sound mediocre even if the rest
of the equipment is very, very high quality. In a typical mono
system, speakers mounted to the left and right of the platform
like a bad habit are just that—a bad habit. Such systems
introduce dead spots and poor intelligibility—which results
in listeners fatigue (or putting people to sleep). Speakers mounted
in the four corners of a sanctuary make the problems of a typical
left-right system seem bearable. Sitting near the rear of such
rooms results in your eyes telling you the sound source is in
front of you, yet your ears tell you it’s behind you. Talk
about confusion! Improperly designed distributed systems can have
the same effect.
What about pew-mounted systems? If you put enough money into
one, use quality speakers and get all of the delay settings done
properly, such a system can work for a speech only system. (In
reality, such a high-quality system is rarely done based on the
extreme expense.) As soon as any music is done, you’re going
to struggle unless the system is turned off. Remember, electricity
flows a whole lot faster through wire than sound waves travel
through the air. Even with the delays set so the speech system
works great, it’s just not right when it comes to music
and congregational singing. Such systems are not worth the expense
and problems for churches to invest in them.
All right, so if the speakers aren’t supposed to be mounted
to the left and right of the platform, in the four corners, or
on the pews, where should they go?, The short answer is that the
speaker(s) should be mounted overhead, usually a few feet in front
of the pulpit, centered left-to-right in the room. This is commonly
referred to as a “cluster” or “point source
speaker system”. This method ensures even sound coverage
from front to back, and proper localization for the original sound
source. Remember, God placed our ears on the side of our head;
we can tell the direction of sound very well on the horizontal
plane, but not in the vertical plane. Therefore, your brain will
combine the visual input from your eyes and the audio input from
your ears and let you know that the minister’s voice is
indeed coming from him, while the speaker system is actually 25
or 35 feet above your head. The exact location of the speaker(s)
is determined by the size and shape of the room, location of the
platform and seating, plus the sound pressure levels required
and other such factors.
Now, for rooms with a ceiling that’s lower than 18-feet,
other methods must be used. This usually includes some form of
a distributed system. Some rooms need only a couple delayed fill
speakers to cover the most rear seating sections, other rooms
must employ many rows of speakers, each one with a different signal
delay time set for it. Such systems cost quite a bit of money,
consider the quantity of speakers and amplifiers. Although most
distributed system use smaller speakers than used in a cluster
system, there are many of them, and many amplifiers, cables, and
delay equipment is needed. In some cases, the cost difference
can be as much as two or three times the cost compared to if the
ceiling were another 15-feet higher.
Just as there’s a sweetspot in a home theater system or
recording studio, there’s a sweetspot in every church sanctuary.
The difference is that in the recording studio or home theater,
the sweetspot is where you should sit to hear the best stereo
sound. Live sound is always mono, but coming from different sources.
In a church, the sweetspot is where the speaker should be placed
to project mono sound into the largest area to achieve a greater
level of intelligibility. This spot is typically very easy to
find with two people. Hey, if you can gain one or two percent
extra intelligibility by just putting the speaker in the right
place, why not? This is a free upgrade! Don’t miss out on
this important aspect. More information on the sweetspot can be
read here.
If you’re working with new construction, the acoustics
of the room should be dictating the size and location of the platform.
This ensures a better environment for audio. You can’t design
a room and then drop in platform and seating to make it look good;
this isn’t using the knowledge we have about the laws of
physics to your advantage. When you begin down the road of choosing
the correct speaker(s) for your room, you must determine how much
coverage is needed. How wide and how deep is your room? Will one
speaker suffice, or will you need two, three, or more? If you
room has a low ceiling and is deep, you’ll need extra speakers
(often referred to as “delayed speakers”) to fill
in the middle and rear seating areas.
Click here for Part 2 |
