Putting together a PA system? 

If you ask 10 people for their opinions of how to put together a PA system, you can easily get 10 widely different answers - some of it due to conventional wisdom that isn't applicable anymore, others simply due to the fact that a LOT of people that dabble in audio have some really big misconceptions.

Let's untangle the truth from the misinformation and help you put together a PA system!

What is a PA System?  What Do You Need to Make it Work?

In it's simplest form, a PA system - or even better a "Sound Reinforcement" system allows you to amplify sounds so that an audience can hear it.

PA systems can be as simple as a megaphone - but as large as a massive system that covers many city clocks for a large celebration.

When we break it down to it's components, it doesn't have to be complicated - sound enters the system through microphones or instruments, which commonly use "DI boxes" to convert the signal to the right impedance.  It then enters the audio console, and goes out to the crossovers/DSP, amplifiers, and speakers.

And while this may sound complicated, it doesn't have to be - as many modern devices have multiple of these functions built in.  A system can be as simple as a microphone that is plugged into a powered speaker, which has the mixer, amplifier, crossover (DSP),  and speaker built in.

Most PA systems that you are planning to use for more than just a simple setup will need these parts broken down - but have no fear - we're here to teach you the basics you need to know to get it right the first time:

Microphones and DI Boxes

Microphones are fairly simple to understand - pretty much everyone has spoken into one at some point in their life!  You probably know that microphones convert sound into electrical signals that then can be brought into a PA system.  There are a few different types of microphones, and then functions that specific microphones are geared towards.

Dynamic and condenser are the (2) main types of microphones that we see in live sound most often.  Dynamic mics tend to work best on louder sources, tend to be less prone to feedback, and also generally have less handling noise.

Condenser microphones are more sensitive, or precise.  They pick up more detail, but sometimes can come across as harsh on some vocals or instruments.  Condenser mics can also be more prone to feedback, but that does not mean they are not good for live sound - they most certainly are and are widely used on vocals, drum overheads, cymbals, and more!

Besides the type of microphone, most microphones are geared towards a specific use or a few specific uses - for example, a vocal microphone, drum microphone, headset microphones for spoken word, or a general instrument microphone.  While that doesn't mean you can't use that microphone for another use, most modern microphones are geared towards a specific type of input and do tend to do very well at that type of input.

The short answer: pick vocal microphones for vocals, instrument microphones for instruments, etc.  If you're new to this, we'd recommend going with most of all dynamic microphones, which can still offer great sound, but tend to be easier to keep from feeding back.

DI Boxes

DI boxes allow you to hook instruments like guitars, basses, keyboards, and more to a PA system.  These instruments come equipped with a 1/4" TS plug and are of a high impedance.  The DI box lowers the impedance and also outputs on a microphone cable for connection to an audio console.

The (2) primary types of DI's are active and passive.  Passive DI's are great on a lot of instruments and come in at a lower cost. 

Active DI's can make instruments with passive pickups sound better and deliver more input volume to the sound console.    Passive instruments are typically going to be guitars or basses without a battery or power source.  Active DI's also require power (typically 48v phantom power from your sound console) and use a transformer to get the job done, which also can add some coloration to the input signal.  In the case of a quality active DI box, this is typically pleasing to the ears, but cheap active DI's may degrade the signal.

When it comes to DI's, it's pretty simple.  Typically, more expensive DI's sound better, and cheaper DI's may degrade the signal more than you like!  Similar to microphones and instruments, you want to buy as high quality of a DI as you can, keeping in mind the quality of the input source...if someone is using a $50 guitar, you probably won't hear a massive improvement on a $300 DI box!  If the input source is high quality, going with a higher quality DI box will give you a better result in most cases!

Audio Console

The microphones, instruments, and other sources all arrive into the audio console and this is where the magic happens: volume levels are set, and tonal controls and dynamics processing is used. 

Simple, analog audio consoles allow you to see everything in front of you, and provide basic adjustments to the signals.

Digital sound consoles give you a full suite of tools to adjust and optimize the sound mix.  Typically, you have the same amount of control as a full analog sound console with many racks of "outboard gear" to get the most out of every signal.  That's not to say that you can't overuse these tools (you certainly can, and it happens far too much!), but having them allows you to get a much better mix put together.

This is why in most cases we'll recommend a digital sound console.  In all but the most simple situations, it tends to give the best results.

Crossovers/DSP

Once the sound leaves the audio console, it moves to the speaker processing.  Crossovers split the signals to go to different speakers (and different drivers within the speakers), and DSP is a modern version of a crossover which includes other controls as well - including delay, equalization, and more.  

Crossovers and DSP may be a separate piece of equipment, or they may be built into your speakers or amplifiers.  If you use active speakers, you will find the DSP is included inside these speakers.

Amplifiers

Amplifiers make the sound louder!  Simply put, this converts the low "line-level" signal that comes from your audio console and crossover/DSP, and converts it into a high-voltage signal with the power required to make the speakers move.  As with the DSP, if you have active speakers, it's built into the speakers.  If not, it is probably in an audio rack backstage.

Speakers

Speakers deliver the sound to our ears - they are the opposite of the microphones, turning the electrical signals into sound we can hear! 

As we've mentioned various places above, there are (2) main types of speakers - active and passive.  Active speakers have amplifiers built into them, which gives them some big advantages - they generally sound better, get louder, and are cheaper than a equal passive speaker + amplifier + DSP.

That's not to say that passive speakers don't have their place.  In hard-to-access areas, installations where you can't or don't want to run power to the speakers, and situations where you don't want the volume/control knobs exposed to the end user and weather (when outdoors), passive speakers still reign supreme.  

However, for most portable and some installed situations, the benefits of active speakers simply outweigh the slight inconvenience of running 2 cables to each speaker instead of one!

Cabling

We would be missing out if we didn't talk about cabling.  Each part of your PA system connects to the others with cabling, and so don't forget about it!

With each type of cable, there are a range of options from cheaper cables to more expensive and pro-grade cables.  The cheapest option is generally not going to last you in a lot of situations, and may be unreliable.  However, the most expensive option also isn't necessary for most users - though it may outlive you, it may also be overkill in terms of cost and quality.  Finding the place where the level of durability you need meets a reasonable cost is key! 

Was that Clear As Mud?

We hope so! :)  Our goal with this guide is to equip you to start looking for the perfect components to make your PA system, and get what you need.  But that's not to say there isn't help available - at Above AVL, we LOVE to help you find the perfect fit in speakers, audio consoles, microphones, and more.  We will package together your system - getting you all of the required components, and getting them to you at your personalized price.

Ready to get started?  Contact us here, or simply add items you're interested in to your cart at AboveAVL.com and hit "Add Items to Quote Request".  We LOVE to help, and there's no obligation - just friendly, knowledgeable folks who want to find the BEST gear for you, help you get it, and be around for the decades to come to continue serving you in your audio, video, and lighting equipment needs.