Sound reinforcement systems come in all different shapes and sizes. There are not two systems that are identical.
The engineer needs to look at the system with some common sense. For instance, you would not place a line array system in a board room…
Each space requires a slightly different configuration. For example, in some room configurations, a line array system might be the best solution, but other rooms may require a point source style design. It is critical that the designer of your system be mindful of this fact and not design solely on popular trends.
Not only does each system require individual attention, but to add another layer of complexity, there are a couple different types of sound reinforcement systems.
One type is a public address system, or PA. These systems are commonly found in concert venues, churches, or auditoriums. The goal of these systems is to noticeably amplify signal inserted into the system.
The second large sound reinforcement system type is simply for voice lift. Voice lift systems are commonly found in boardrooms, and venues such as reading rooms for the fine arts. Voice lift is simply there to provide each listener with a level as if the person was standing within a few feet of them. This means that anywhere in the space, you should be able to hear the speaker at normal conversation levels.
Even though there are multiple types of sound reinforcement systems, there are still three main things that an engineer must think about while designing a system for a church or another type of client.
The first thing an engineer does is the "Think It." This may sound simple, but what it means is that the engineer needs to look at the system with some common sense. For instance, you would not place a line array system in a board room, just as you wouldn’t use ceiling speakers for a full band application. This is obviously a crazy scenario, but in most situations, it is not so clear cut.
The thinking requires the engineer to look at speaker specifications, CAD layouts of the space, and requirements from the client. Sometimes the differences in these requirements are subtle, but by completing this step, you will get a good bit of the way to completion. The next steps should simply be validation with possible slight modifications.
The second thing that an engineer will do is "Math It." This is where a lot of folks start to fall away. It is a much more tedious process, but we need to take the time and calculate the actual math of the design. This requires trigonometry, a good calculator, some scratch paper, and some online tools provided by industry leaders. .
Engineers need to calculate power requirements of the system, heat loads for HVAC requirements, weight for structural requirements, conduit fills, jam ratios, coverage patterns, and more. A lot of these can be easily calculated with a pencil and paper, but others such as coverage patterns can be a little more time consuming. This is why a lot of engineers will turn to tools such as ease for coverage and uniformity modeling. These models can provide a very detailed survey of coverage in your space.
Doing the math, though, does not guarantee that the system will be great. The models and math are only as good as the information provided. Even though the possibility for error is available, the math does give you some extra information into the system, making sure that the system will work as designed.
The third thing is to "Draw It." Every detail is important. It is best to assume at every instance that no one has any clue what they are doing and your drawings are going to be the instruction guide to the installation team. It is very easy to draw a system and require field verification for installation, but it adds time to the end of the project. Just like every step above, the better the information and the more time spent, the better the end result will be.
Many will note that all of this can take a lot of time to complete, before the project is underway and you might be on a tight deadline. It is well documented by industry leaders that one hour in "the shop," will save three hours in the field.
The drawing stage really is the culmination of all the information that the engineer has gained over the course of the design process. Others may not have been privileged to that information, or it may be taken for granted that something should be general knowledge when it may not be. These holdups or assumptions could cause a lot of time loss at the end of the project.
When it is all said and done, you cannot take a system and carbon copy it from one venue to another. Each system requires the engineer to take time to think about the system and apply some logic and industry knowledge to it. It takes time to do the hard scratch work in the design.
Getting out the piece of paper and pencil can add to the time of the project, but it will typically help the design of the overall system. Then finally, take the time and detail out the system. Give as much detail as you can muster and be intentional with details to the point that someone could walk in and figure out the system from your drawings.