PA System Factors To Consider

Question

What are some of the things to consider and devices to have when creating a PA system for a church to be used both indoors and outdoors...?!

Answer 1

Bare minimum requirements:

• Microphones and/or DI boxes
• Mixer
• Power amp(s)
• Speaker(s)
• All the necessary cables

Note that the mixer and power amp can be purchased in combination called a "powered mixer", or the power amps and speakers can be bought in combination called a "powered speaker".

Very desirable extras (but not 100% required):

• Snake
• Feedback control
• Mains equalization
• Crossover/speaker management
• Reverb processor
• Power conditioners/distribution and quality extension cords (20 Amp rating if you can get it)
• Cases and racks to hold everything
• Tarp or rain fly, poles, and lines to set up over the mix position outdoors if all-weather operation is needed

Nice to have, but not as important as above:

• Dynamics processing (compressor/gate)
• Other effects (delay, flanger, distortion, etc.)
• Recording capability
• Dedicated lighting for all controls (may not be needed for daytime, brightly lit, worship music environments)

Note that there are many digital mixers available that combine the mixer, equalization, reverb, dynamics, effects, and recording capability in one unit.

Answer 2

THINGS TO CONSIDER are as follows:

What is the size of your audience or venue. The bigger the room, the more powerful your amplification system will need to be. Sound reinforcement outdoors can present even greater demand on your amplification needs. Outdoors you have more ambient noise (traffic going by, planes flying over, wind blowing, etc.) and no surfaces to reflect sound back. The larger the audience outdoors, the farther some of them will be from the main speakers. Therefore the more power you need to achieve the needed volume without distortion or to drive more speakers interspersed at midpoints through the audience.

How many instruments and microphones will you need to amplify. You will need a mixer with enough of - and the correct type of inputs, for everything you need to amplify. For example if you have 4 singers who will require microphones, plus you want to mic your snare and kick drum, and mic your bass cabinet and plug in your keyboard, you will need a mixer (or combination of mixer's) with at least 7 XLR microphone inputs and a two channel stereo input for your keyboard. It would probably be a good idea to have a few extra 1/4 inch inputs in case you add a guitar player or two in the future.

How many main speakers you need. The main PA speakers ("mains") are what broadcast the sound to the audience. Depending on the size and configuration of your indoor area and how spread apart your outdoor audience might be, you may need more than just two main speaker cabinets to cover a wider area. If the audience will be less spread out (like in a rectangle not much wider than the stage area), and not too far from the stage, you might be able to get by with only two main speakers - one on either side of the stage.

How many stage monitors you will need In addition to the mains for the audience, you will need monitors for the performers so they can hear themselves. The singers especially will need to be able to hear the accompaniment from the instruments and hear themselves. Typically your mains will be in front of the microphones or you will get feedback. And standing behind the mains, the vocalist won't be able to hear what they need to hear. Monitors are usually placed on the ground and positioned in front of the microphones but facing the performer. You will need enough monitors facing the musicians and vocalist, so that all the performers can hear the music. Depending on the placement and dispersion pattern as well as the placement of the musicians on stage - you might be able to use one monitor to cover two musicians.

DEVICES YOU WILL NEED:

Microphones - you will want one for each singer and a couple of backups in case one is dropped and the diaphragm is ruptured or a wire breaks loose (it happens). For live use, the most durable will be dynamic microphones such as the Sure SM-58 (as opposed to more fragile condenser mics which require phantom power). Of course you will also need Mic Stands and Mic cables and Mic clips to hold them on the stands. If you want to mic your bass cabinet (amplifier) you might want an instrument mic such as the Sure SM-57 and possible an instrument mic stand (although you can just drape it over the top of the cabinet). If you mic your drums you might consider dedicated drum microphones and you will need boom stands for miking anything other than the kick drum. Outdoors you may also need additional windscreens to go over the microphones because the internal windscreen may not be enough if there is a great deal of wind.

You might find it very useful to have at least one wireless microphone system to permit the speaker or performer to move around on stage or among the audience.

I will assume the keyboard player will have cables to plug in the keyboard to the mixer and the bass player will have an instrument cable to run from his guitar to his bass amp.

You will need speaker stands to mount the main speaker cabinets - one for each speaker.

You will need extension cords long enough to reach your power source. You may be able to use one heavy duty cord to bring power to the stage (your outdoor staging area may not have power close by) and then shorter cords to go from your main distribution box to your mixer, your amplifiers, your monitors if they are powered, your main speaker if they are powered, any pedal boards or effects processors, your keyboard, and any electrical powered lights you might want or need including music stand lights.

As stated in part one you will need a mixer with enough inputs for all your instruments and microphones. Here you have an option to go with a passive (non powered) mixer and use powered (internally amplified) speakers - OR use a powered mixer or power amps to drive passive (non-powered) speakers. The best option will ultimately depend on your overall set up and the amount of speakers you need to cover your indoor and/or outdoor venue.

There are advantages and disadvantages to each type PA system (powered speaker/passive mixer) vs. (passive speakers driven by a powered mixer or power amp). That is an entire subject in and of itself and beyond the scope of this answer. Feel free to post another question to learn more about this topic.

If you plan to mix the sound from the stage - you will also need a stand or small table to place the mixer on . It's difficult to adjust and fine tune the control knobs if it's sitting on the ground. An X brace keyboard stand with a small piece of plywood works well for this.

If you wish to have the mixer in a control room or have a sound engineer mix the sound from a position in or near the audience (recommended), you will want a table and chair for the mixer and sound engineer and will need a "stage snake" to run all the inputs from the stage to the mixing console. A snake is basically a bunch of cables (XLR and 1/4) encapsulated in rubber sheathing so that instead of 12 cables running from the stage to the mixer to trip over - you only have one. Plus it makes it much easier to manage the cables. For outdoors, your sound engineer will probably appreciate a small tent to provide shelter from the sun and rain (if that ever sneaks in on you).

While on the subject of rain - if your are setting up a PA system outdoors and there is any possibility of rain and you aren't under a covered pavilion, you will want to have quick and easy access to tarps to throw over your sensitive electronics and instruments in case of a sudden rain. Heavy duty trash or leaf bags make great speaker covers for inclement weather. If rain is possible, designate a few folks in advance to handle tarping each of the various components so it happens quickly. "Bill you are in charge of putting this trash bag on the left main speaker - Amy, you are in charge of the right main speaker - here is your trash bag - keep it handy" etc. .

It's not a part of the PA system but your musicians and singers may need a music stand or tablet mount for their music sheets if they aren't going to memorize all the songs to be performed.

And of course you will need the main speakers and stage monitors as discussed in part one. You will also need speaker cables to connect the mains and monitors and if the speakers are powered, you will need extension cords for each speaker.

Depending on the equipment your bass player is using, you might be able to use a DI box to run the signal from his instrument directly to the mixing console without a need to mic the bass cabinet.

More elaborate PA systems designed for permanent installation in a venue, or for very large outdoor gatherings, might have things such as power conditioners, standalone equalizers, compressors, feedback suppressors, crossovers, USB Interface, MIDI processors and other tools.

From your question, it sounds as though you are looking for a rather portable dual purpose system that you can move from indoors to outdoors. There are quite a few options but hopefully this will give you a good place to start. Or at least tell you what you need to learn more about and how to better define your needs.

Perhaps the sound director or production manager at another church might be willing to share their knowledge to help you decide what type system will best fit your needs.

Good luck!