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Greetings! I will tell you up front that this article is in regards to speaker placement in Houses of Worship. Please feel free to enjoy the article, but if your application is live touring sound, weekend band, or other application, please contact me (see below) for a more application-specific discussion of your needs as those applications can be vastly different than the installed systems discussed in this article.

In this issue, we'll discuss speaker placement and how it relates to your congregation's ability to hear the message, whether spoken or musical. The decision you make on the location of your sanctuary mains and monitor speakers will have a decided impact on the success of your presentation.

A single source of sound is best for the spoken word, whenever possible.

In a perfect world, as it relates to audio systems for worship, we always try to place the sanctuary main speakers in a central cluster above the front edge of the chancel riser. The speaker or speakers are selected to provide pattern coverage over the entire seating area without putting acoustic energy on the walls, floor or ceiling. When we put sound on people, it is largely absorbed and only minimal reflections continue elsewhere in their journey about the room. When the pattern coverage is poorly designed, putting acoustic energy on highly reflective surfaces such as walls, floors and ceilings, the reflected sound can pass the listener's ears several times, creating a lack of enunciation and speech intelligibility.

The properly designed central cluster allows the sound to reach the listener only once, thereby allowing for the most concise possible listening situation. In many sanctuaries, however, there are physical limitations such as low ceilings or tall crosses that require an alternate consideration.

What if we can't use a central cluster?

When we are forced to consider an alternate placement, it is usually left side and right side. It is important to remember that sound will arrive at two different time intervals to people seated along the sides, and so we must attempt to select speakers with a narrower coverage pattern. We attempt to put sound on people at the left with the left speaker, and on people at the right with the right speaker, with as little acoustic energy crossing over the middle as possible.

How high should the speakers be hung?

Generally speaking, we try to hang the speakers as high as possible (however not to exceed 18-22 feet) in order to increase the distance from the loudspeaker to the front pew. If the room has extremely low ceilings, we can arrive at a condition where people seated at the front are complaining that it is too loud while the people at the rear are commenting that the sound needs to be turned up.

In such an instance, it is advisable to turn the system down to a comfortable level and hang a second and even third set of speakers perhaps every 25-30 feet as we grow in distance from the chancel. Since sound traveling through the air takes time, the second set of speakers will need to utilize a time delay so that the sound traveling from the chancel coincides perfectly with the sound emanating from the second set of speakers. A third set of speakers will have to be delayed at yet a different setting to coincide with the sound emanating from the first two sets of speakers. In this manner, all sound source material reaches the ears of the listener at the exact same moment in time, regardless of how far back they are seated in the room, thereby maintaining speech intelligibility.

Though a sanctuary may have adequate ceiling height, if the room is very deep it is still advisable to use multiple speaker placements on delay lines. Even if the chancel mains could be turned up loud enough to be heard at the back of the room, the sense of distance is audible (due to wall and ceiling reflections) and intelligibility is again adversely affected.

How can we minimize the possibility of feedback?

In spite of the general public's degree of sophistication in regards to quality audio, it's not commonly understood that mics need to be out of the live sound field whenever possible in order to minimize the possibility of feedback and annoying lingering overtones. In other words, keep speaker enclosures in front of the mics, not behind them. Of course, almost all Pastors wear wireless mics and many like to move about the room while speaking. A good sound tech will be able to provide equalization so this may be done.

Attempt to keep monitor sound confined to the chancel riser.

Monitor speakers are a wonderful benefit for the performers using them but can have a deleterious effect on the sanctuary sound. If the monitors are positioned so that the monitor mix bounces off the back of the chancel and reflects back out to the congregation, it is now combining at a different time interval with the sanctuary main mix and we have now adversely affected the speech intelligibility we had been striving so hard to create out front.

How loud should the monitors be?

Monitors should be just loud enough to keep the performers comfortable. If the monitors are too loud in relationship to the sanctuary mains, no amount of positioning will help maintain clarity in the general seating area. Since many praise band players are now middle-aged veterans of once-youthful rock bands, gently remind them that the purpose of the monitor line is to lend support and enunciation so that they may execute the material more perfectly. If the monitors are intended to provide a studio-perfect mix of all instruments and voices for the listening enjoyment of the players, then you will need to be blessed with highly experienced and adequately funded audio technicians. Many larger churches in metropolitan areas are able to create this benefit for the praise musicians.

There are several other topics related to speaker placement that we have not discussed here. If you'd like a continued dialog along these lines, or to discuss anything to do with live audio, please contact me at 1-800-373-2000 xt 1250 or email me at This e-mail address is being protected from spambots. You need JavaScript enabled to view it . I'd love to visit with you!

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