9 Essentials of a Professional Audio System

As the first real informational post, I would like to say thank you for stopping by and let’s get started.

This post will explain the bare necessities of a live sound system that can handle drums, bass, guitar, piano, and vocals. The overall amount of gear that is necessary for the perfect sound is often overlooked because of common misconceptions. This blog post will help guide new venues, bands, churches, and solo acts to gather accurate information that will help engineers and purchasers to make an educated decision when putting together a professional live sound system.

An overall professional sound system includes,

1. Mixer (to control speakers and microphone volumes)

2. Main Speakers (for the audience to hear)

3. Sub woofers (adds extra deep bass to the main speakers)

4. Monitors (speakers that musicians use to hear themselves on stage)

5. Graphic Equalizer (to equalize each pair of speakers)

6. Snake (a source of inputs on stage that allows easy connection to the sound system)

7. Microphones (Choose the right type and plan for the future)

8. Cables (to connect speakers and microphones to mixer)

9. In some cases, power amps but powered speakers with amplifiers integrated have recently become the industry standard



-The above list expresses the essential components that are necessary for a professional audio system in a church or live sound venue. Now to briefly explain each element of a professional sound system.



First the MIXER!

A mixer is the central input source for instruments and microphones. A mixer allows the engineer to control the overall speaker volume and the individual microphone volumes. A mixer is helpful because microphones, instruments, and speakers need a central point of control. A mixer comes in several sizes and can be very useful in large and small sound systems. Think of a mixer as a home theater system receiver, the television plugs into the receiver and the receiver controls the home theater speaker volume.

When buying a mixer, it is important to know how many microphones and instrument you will be plugging into the mixer. Companies are often deceiving in how mixer inputs are explained. The consumer will see a 12 channel mixer for $120, but when they get to the store, the 12 channel mixer only has four mic inputs. Make sure to investigate exactly how many microphone inputs there are on the mixer you choose.


When buying a mixer I recommend,

A. How many actual microphone input channels there are on the mixer

B. find out how many auxiliary outputs there are on the mixer? (Auxiliary outputs are used to send sound to floor monitors for musicians to hear themselves)

C. Are there any sub-group outputs on the mixer? (these are used to control a sub woofer or to send to a recording unit)

D. Are there any vocal effects integrated into the mixer? (Echo, reverb, delay)

E. Check to see which channels have GAIN knobs or Preamps for each channel on the mixer. A preamp will have to word “gain” or “trim” near the knob. The knob is located at the top of the channel below the mic and instrument input. A Preamp amplifies a microphone or guitar to an audible volume so that it can be heard through a speaker.


-These few questions can make the buying experience easier and can offer a lot of insight into whether this is the mixer for your venue or not.



2-Main Speakers
Now for Main Speaker!

The word Mains is often used in a live sound setting. The word Mains pertains to the main speakers that are pointing at the audience. Mains are specifically meaning the full range speakers and not the sub woofers. A Full Range Speaker is essentially a typical pa speaker. Full Range means that high , mid, and low end frequencies all play through the speaker. An example of a speaker that is not full range would be a sub woofer. Just like a car sub the sub woofer focuses on bass frequencies, and you will not hear vocals out of a sub woofer.

Mains are usually 12 inches to 15 inches live sound PA speakers. This post will focus on powered speakers, meaning the speaker has a built in amplifier and plugs into the wall just like a lamp. Powered speakers are now reaching up to 2000 watts in consumer and professional settings. The technology that has revolutionized the audio industry has transformed that ability to pack a ton of wattage into a self-contained unit. Having the ability to use a speaker with 2000 watts integrate cuts down on user error and simplifies that installation process so that relatively inexperienced individuals can now take advantage of the technology and competently set up a professional live sound system.

Speakers are much more than wattage, relying on the wrong ratings on speakers can be misleading pay attention to SPL and make the right choice. SPL stands for sound pressure level, which is essential how much volume the speaker can handle. SPL is rated in decibels, abbreviated to DB. Decibels are how sound is measured, so keep your eye out and make the right choice.


I recommend these speaker ratings,
126db SPL 1000watts+ on an inexpensive investment
129db SPL 1000watts+ and up on a great investment



3-Sub woofers
Gotta love that bass!

A sound system with no sub woofers can still be a great sound, but subs genuinely create a unique experience with live sound. Sub woofers focus on bass frequencies and take stress off of the mains because bass frequencies have high sound pressure. In the previous paragraph mains are full range speakers, but when a sub woofer is connected to the system it is common to remove bass frequencies from the mains. There is often a switch that removes bass from the speaker labeled, EXT SUB. If your speaker does not have a switch like this then it is most likely located on the sub woofer.

Bass frequencies take up a lot of power and require more wattage, so having a dedicated speaker to those frequencies is beneficial. Sub woofers take stress off of the main from reproducing bass frequencies, they enhance the musical experience on a subharmonic level, and sub woofers reproduce deeper bass frequencies than a full range speaker.

Sub woofers, just like speakers are much more than wattage. Relying on the wrong ratings on speakers can be misleading pay attention to SPL and make the right choice. SPL stands for sound pressure level, which is essential how much volume the speaker can handle. SPL is rated in decibels, abbreviated to DB. Decibels are how sound is measured, so keep your eye out and make the right choice.


I recommend these speaker ratings,
126db SPL 1000watts+ on an inexpensive investment
129db SPL 1000watts+ and up on a great investment



If you can’t hear yourself, you need a MONITOR!


Monitors are essential for the musician, Pastor, and even the DJ. A monitor is a full range speaker that is usually 12 to 15 inches. In a live sound setting the monitor is placed behind the mic facing up towards the speaker, singer, or musician. The idea is to give the user a source to hear themselves and to monitor their own performance.


-Monitors are essential parts of a successful sound system and are necessary for musicians to deliver a meaningful performance.



5- Graphic Equalizer
Do your speakers squeal? You need a 31 Band EQ!!!

There is often a misconception that lead to consumers not buying graphic equalizers. 60% of local churches have feedback problems and complain about microphones squealing or not being able to raise the volume loud enough in a venue because of the squealing microphones. A sound loop causes feedback, when an individual speaks into a microphone the sound comes out of the speaker then that same sound coming out of the speaker is picked up by the microphone. When the sound exits the speaker and reenters the microphone, that is what is called a feedback loop. The feedback loop begins to oscillate so fast out of the speaker and back into the mic that it sounds like a loud squeal or low rumble.


Feedback is a complex and very unforgiving, with one 31 band graphic equalizer for each pair of speakers your church can win the battle against feedback.



AHHHH it’s a SNAKE!!

In live sound, a snake is here to help and organize your cable runs. A snake in a live sound setting is a bundle of cables that has been bundled into a single 50-250 foot long input source for the musicians on stage. In most settings, mixers are placed in front of the stage, at least 50 feet away. The individual 50 foot cable runs would be very costly and inefficient when connecting multiple microphones and instruments to a mixer.

The snake plugs into the mixer on one end and the other end has several inputs. The input end of the snake is placed on stage so musicians can connect their instruments and microphones into the snake. The snake also has speaker outputs and is an easy way to connect mains, monitors, and sub woofers.




Wireless or wires that is the question!!

One of the most crucial parts of a sound system is the microphones being used. The reality is there is more than just the sound of the microphone that goes into the quality of a microphone. Handling noise, polar pattern, and eq are important measurements of the quality of a microphone.

Most industry standard microphones start at $99.98; this has been common since I can remember. The SM58LC and the Sennheiser E835 are currently the leading industry-standard handheld microphones. These microphones offer low handling noise, which is literally the noise the mic makes when being moved around. A singers hand moves a lot, and it becomes apparent when using cheaper microphones. When using cheaper microphones, external vibration are amplified by a microphone and projected out of a speaker which can have adverse effects during a performance or service.

Polar patterns are how microphones picks up sound. The most common polar patterns for live use are cardioid, super cardioid, and hyper cardioid. These different polar patterns depict how a microphones pick up sound by relating it to an image of a heart shape. A regular cardioid pickup pattern is the most commonly used pickup pattern, it is used on both the industry-standard SM58 and the E835. Cardioid picks up sound from the front and rejects the sound coming from behind the microphone. Super-cardioid is essentially a tighter pickup pattern and rejects sound from the sides but allows some sound from the back. The hyper cardioid polar pattern is the narrowest of them all and is very directional meaning it only picks up sound from a specific spot on the front of the mic.



-Each polar pattern is used for specific settings and can both benefit or hinder a performance depending on how the surroundings in the particular venue.



Cables on our plane!? Oh yeah, we’re on tour!!

The most under appreciated and absolute most important piece to an entire professional audio system, the cables. The first piece that connects your new expensive $100 microphone to your new $500 mixer should not be a cheap throw in. The reality is that unlike anything else in any industry, most worth it microphone and instrument cables come with a lifetime in store swap warranty. I say invest! You may spend $7 more from the cheap microphone cable to get the lifetime warranty cable, and it is absolutely worth it.

Cables in general, made up of a microfiber and copper cabling. The copper cabling is intertwined to prevent noise and buzz. The better the cable, the better the resistance to noise and buzz, also more frequency reproduction. Each major retailer offers their version of lifetime warranty cables. Since most good cables come with a lifetime warranty, the differences lie in the frequency reproduction, the noise resistance of the intertwined copper wires, and the quality of microfiber protection. The microfiber is the cotton that is between the copper wire and the plastic cover of the cable.




9-Powered Speakers and Amps
I used to carry a heavy amp, and now I don’t!!

Power amplifiers and powered mixers were always the biggest draw back to owning a portable system; because they used to be extremely heavy due to the transformer inside. New technology allows for increased wattage and a lighter load. A digital processing chip allows for a smaller transformer and a lighter power amp. As the technology continues to evolve, 500-watt power amps are a thing of the past, 1100 watts, to 2000 watts are the industry standard in a self contained powered speaker. The evolution of digital processing has accelerated the production of high wattage powered speakers. The best part is there is little possibility for user error.

Today’s technology is causing power amps to be a thing of the past, but there is still a reason to use power amps and many situations that call for power amps. Not all churches or venues have power outlets where the speakers are being hung, in which case it is easier to run a speaker cable to the speaker versus installing a wall power outlet.



-In summary, the evolution of digital processing has given manufacturers the ability to make a powered speaker more powerful than ever. Powered speakers plug into a wall outlet and offer consumers high wattage, and at the same time, powered speakers take harmful user error out of the equation.



This has been a journey!

-Thanks for sticking around till the end, I hope this helps broaden your conceptual ideas of a professional audio sound system.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s