You’ve all heard it, that squealing, irritating sound that rises in volume until everyone has to cover their ears and the speaker rolls their eyes. Everyone looks to the soundman in disgust and the entire mood of the event, from a wedding to a Sunday morning mass, is destroyed. Hopefully you haven’t blown out the tweeters. This is an example of problematic audio system feedback.
So… what is feedback exactly?
Feedback starts by a sound entering a microphone, traveling through the electronics and then to the loudspeakers. Since the system is designed to take a small sound and increase it to a loud sound, the sound emerges significantly louder from the speakers. Now that sound is out there bouncing around. If enough of it gets back into the microphone, then the process starts again, each time increasing a little bit until the squeal is heard. This is known as a feedback loop.
Each room and each sound system have certain frequencies that are accentuated. These frequencies tend to be the core frequencies that feedback on a regular basis. The amount of loudness a system can produce before the feedback begins is known as gain-before-feedback. Every system has its tipping point, but there are things that a savvy operator can do to prevent feedback from ruining the day (or at least the sermon).
How can you prevent feedback?
Properly tuning the room should always be the first thing that you do. This means finding a qualified consultant to determine which acoustical absorbers to use, how much to use, and where to place them. I can’t emphasize this enough in Houses of Worship, which tend to forego wall treatments in favor more electronics. There are many materials available which can be placed which will both complement the interior design of any facility and help curb the sound energy from bouncing around.
Purchasing the right microphone is the next thing. Good professional microphones will have a pickup pattern that is more in the front of the mic, called a cardiod or supercardiod pattern. They will also reject as much sound as possible from entering the rear of the mic element so that your monitors will not cause feedback. Additionally, the better the mic, the more even the frequency response. Uneven frequency response adds to the imbalanced resonating frequencies.
Next is not only choosing the right monitors, but more importantly placing them correctly. Try to avoid speakers with a Piezo electric tweeter as these are harsh and uneven in their frequency response. Then place these speakers so that your speakers will be about 60 degrees off axis from the microphone. This tends to be the place where microphones pick up the least.
If you’ve done these previous three things, then the next place to look is at your electronics. Usually on most mixers there is the High Pass (or Low Cut, this is the same thing) filter. Engage this switch on all the vocals. This will at least remove the low end rumble and possibility of low frequency feedback.
Parametric Equalizers are your friend with regard to feedback. If you don’t have one as a piece of outboard gear, then you should have at least one in the EQ section of your mixer channel strip. There will be at least two knobs, the frequency selector and the gain cut/boost. The next paragraph explains how to use them to your advantage.
How to make feedback your friend.
The process of using feedback in a positive manner is known as “ringing out the system”. You force the system into a feedback mode, and then notch, or cut, those offending frequencies. This should be done in the room before anyone comes in since it can be a painful process to a listener. The procedure is as follows.
Set everything up on the stage. Turn the input gain on the channel strip of the mixer down as low as it will go. Bring the mains up to the 0 mark, and bring the channel fader up to 0 as well. The EQ section should be flat, with the High Pass/Low Cut switch engaged. Slowly bring up the gain knob until the system begins to feedback, and then bring it back down just until the feedback is gone. Look to the parametric EQ section of that channel. Turn the parametric gain knob up about three to six db. Sweep the parametric frequency selector until you find the feedback frequency. Take the parametric gain knob and turn it to three to six db below 0. If there are more parametrics in your channel strip, do the same thing for those frequencies. You should now be able to get three to six more db of gain out of your microphone, which is about twice as loud!
Feedback Destroyers are useful for systems that have no dedicated operator. Usually, they find the first feedback frequencies and cut them, and then there will be other frequencies that are searching for the next frequencies that pop up. Their use should be limited however, since these roving filters cause a sweeping and undesirable sound as they are doing their job.
Feedback is inherent in every sound system, but knowing what it is and how to work with it can help you get the maximum performance out of your equipment. If you need help figuring this all out, please contact Proaudionet Consulting by visiting our contact page or send us an email! We'd love to hear from you.
Saturday, July 23, 2011
Need an Audio Consultant in Central Florida?
Need an Audio Consultant in Central Florida?
Central Florida is a wonderful beautiful area. With plenty of talent in the area and numerous venues in which to perform, there is a need for qualified engineers to assist with the infrastructure of your system.
How do you know you need an audio consultant? If your existing system is not performing like it did when it was installed, if you are experiencing persistent feedback, if there are new noises in the system, or if no-one knows your system since your old engineer moved on, then it’s time to find someone who can help.
But where to find an audio consultant in Central Florida?
Call on Proaudionet! We have over 25 years of experience in the field. We’ve provided help to Churches, Clubs, Bars, Restaurants, Schools, Houses of Worship, Educational Facilities, Opera Houses, Recording Studios, Production Companies, Theme Parks, and Nightclubs. From designing the complete system, to systems integration, to training personnel, we are your one stop shop when it comes to audio consulting.
Our primary area of travel is Central Florida. That’s along the Interstate 4 corridor from Lakeland to Daytona, and includes Orlando, Winter Park, Maitland, Altamonte Springs, Deland, Debary, Melbourne, Titusville, Christmas, and Daytona to name most of the towns in this area. We’ll even travel to Saint Augustine (we love the Ancient City)!
If you’re in this area and you need an audio consultant, please visit our contact page, or email us. We’d love to hear from you! And if you just need a few words of advice, that’s always free.
Central Florida is a wonderful beautiful area. With plenty of talent in the area and numerous venues in which to perform, there is a need for qualified engineers to assist with the infrastructure of your system.
How do you know you need an audio consultant? If your existing system is not performing like it did when it was installed, if you are experiencing persistent feedback, if there are new noises in the system, or if no-one knows your system since your old engineer moved on, then it’s time to find someone who can help.
But where to find an audio consultant in Central Florida?
Call on Proaudionet! We have over 25 years of experience in the field. We’ve provided help to Churches, Clubs, Bars, Restaurants, Schools, Houses of Worship, Educational Facilities, Opera Houses, Recording Studios, Production Companies, Theme Parks, and Nightclubs. From designing the complete system, to systems integration, to training personnel, we are your one stop shop when it comes to audio consulting.
Our primary area of travel is Central Florida. That’s along the Interstate 4 corridor from Lakeland to Daytona, and includes Orlando, Winter Park, Maitland, Altamonte Springs, Deland, Debary, Melbourne, Titusville, Christmas, and Daytona to name most of the towns in this area. We’ll even travel to Saint Augustine (we love the Ancient City)!
If you’re in this area and you need an audio consultant, please visit our contact page, or email us. We’d love to hear from you! And if you just need a few words of advice, that’s always free.
Saturday, July 16, 2011
Links
Here are some of our friends in the audio world. Please visit their websites.
Directory Audio Net
Visit our friends:
Directory Audio Net
Visit our friends:
Friday, July 15, 2011
Audio Problem Common to Houses of Worship
Almost every church, temple, synagogue, or other House of Worship shares the common audio problem of intelligibility. Yet, most Houses of Worship throw their money at more electronics instead of addressing the primary problems with their acoustics.
The primary need of any church or House of Worship is to deliver their message. Therefore if the congregation can't understand the worship leader, for whatever reason, then that need is unfulfilled. Emphasis is usually placed on the electronics of the sound system to try and correct the problem, and little attention is paid to the acoustics in the space.
The acoustics of the room should be the primary environmental aspect to be addressed. Why? If the acoustic problems are fixed first, then the electronics will have a much easier time delivering a clean message.
The most common sound issue is the long decay time in these large and beautiful spaces. As the worship leader has speaks the first word, the sound waves bounce all around the room, off the walls, off the windows, off the ceiling, and every other reflective surface. But as the worship leader begins to speak the second word, the reflected energy from the first word is still arriving at the members of the congregation. The result of this is that the congregation will have difficulty hearing the second word, and the next word, and so on. The longer the decay time, the more garbled the message.
So how to you address this common audio problem in your church? Contact an audio professional (and you should), but first understand that some of the audio energy should be removed from the room. Acoustical panels, heavy drapes, ceiling tiles, and more can help alleviate this problem by absorbing the direct sound wave and preventing it from being reflected towards the congregation.
How much acoustic treatment is needed? Every House of Worship, church and temple is different and the approach should be tailored to the specific problems of the space. However, roughly figure that about 25% of the available wall space should be treated.
Does this mean that the walls will be covered in unsightly materials? No, not at all! A talented acoustic designer will select materials that exemplify the overall message of the sanctuary, yet be able to remove enough of the original reflections so that the message arrives clean and intelligible.
If you need an experienced consultant to fix this problem in your House of Worship, then please feel free to drop us line, we'd love to hear from you!
The primary need of any church or House of Worship is to deliver their message. Therefore if the congregation can't understand the worship leader, for whatever reason, then that need is unfulfilled. Emphasis is usually placed on the electronics of the sound system to try and correct the problem, and little attention is paid to the acoustics in the space.
The acoustics of the room should be the primary environmental aspect to be addressed. Why? If the acoustic problems are fixed first, then the electronics will have a much easier time delivering a clean message.
The most common sound issue is the long decay time in these large and beautiful spaces. As the worship leader has speaks the first word, the sound waves bounce all around the room, off the walls, off the windows, off the ceiling, and every other reflective surface. But as the worship leader begins to speak the second word, the reflected energy from the first word is still arriving at the members of the congregation. The result of this is that the congregation will have difficulty hearing the second word, and the next word, and so on. The longer the decay time, the more garbled the message.
So how to you address this common audio problem in your church? Contact an audio professional (and you should), but first understand that some of the audio energy should be removed from the room. Acoustical panels, heavy drapes, ceiling tiles, and more can help alleviate this problem by absorbing the direct sound wave and preventing it from being reflected towards the congregation.
How much acoustic treatment is needed? Every House of Worship, church and temple is different and the approach should be tailored to the specific problems of the space. However, roughly figure that about 25% of the available wall space should be treated.
Does this mean that the walls will be covered in unsightly materials? No, not at all! A talented acoustic designer will select materials that exemplify the overall message of the sanctuary, yet be able to remove enough of the original reflections so that the message arrives clean and intelligible.
If you need an experienced consultant to fix this problem in your House of Worship, then please feel free to drop us line, we'd love to hear from you!
The Speed of Sound
The easy answer to the question "What is the speed of sound" is 1126 feet per second, or 343 meters per second. The full answer is a little more complicated.
Typically, the speed of sound is measured in dry air at 68 degrees Farenheit at sea level. Here in Central Florida, that at least makes on part of the equation simple! As the temperature, humidity, and barometric pressure change, so does the speed.
How does this help us in the audio world? Usually in Houses of Worship, there are many acoustical problems. The use of broadband and low frequency absorbers are used to remove some of the acoustic energy in a room. As you know more of the problems in your particular room, you can pinpoint frequencies and design solutions to nearly pinpoint these problem frequencies. The greater the accuracy with your treatments, the more natural the sound that the congregation hears.
For example, suppose you are having feedback in the 1Khz range from the podium mics. By using a calculator, you will find that the Speed of Sound (1126ft/sec) divided by 1000 equals 1.126 ft. Lower frequencies have a longer wavelength, higher frequencies have a shorter wavelength. But now that we know that we have a wavelength of 1.126ft, we can create acoustical absorbers that use this dimension. I would suggest using absorption blocks of a least this length and width. As for the depth, the depth of 1.126ft is probably unpractical, so choose the deepest depth that would work in the room. How many of these panels should you use? As many as you can, but you probably won't hear a difference until you cover at least 25% of the back wall.
Hopefully this example helps, and gives you a practical use of the speed of sound. If you need help with your House of Worship, and you're in the Central Florida and Orlando area, please drop us line and we'll be happy to help you out!
Have a wonderful day.
Typically, the speed of sound is measured in dry air at 68 degrees Farenheit at sea level. Here in Central Florida, that at least makes on part of the equation simple! As the temperature, humidity, and barometric pressure change, so does the speed.
How does this help us in the audio world? Usually in Houses of Worship, there are many acoustical problems. The use of broadband and low frequency absorbers are used to remove some of the acoustic energy in a room. As you know more of the problems in your particular room, you can pinpoint frequencies and design solutions to nearly pinpoint these problem frequencies. The greater the accuracy with your treatments, the more natural the sound that the congregation hears.
For example, suppose you are having feedback in the 1Khz range from the podium mics. By using a calculator, you will find that the Speed of Sound (1126ft/sec) divided by 1000 equals 1.126 ft. Lower frequencies have a longer wavelength, higher frequencies have a shorter wavelength. But now that we know that we have a wavelength of 1.126ft, we can create acoustical absorbers that use this dimension. I would suggest using absorption blocks of a least this length and width. As for the depth, the depth of 1.126ft is probably unpractical, so choose the deepest depth that would work in the room. How many of these panels should you use? As many as you can, but you probably won't hear a difference until you cover at least 25% of the back wall.
Hopefully this example helps, and gives you a practical use of the speed of sound. If you need help with your House of Worship, and you're in the Central Florida and Orlando area, please drop us line and we'll be happy to help you out!
Have a wonderful day.
The Use of Sound Effects in a House of Worship
The use of sound effects in Houses of Worship can mean many things. First, we need to determine what is a sound effect?
Sound effects can be broken down into 2 basic categories, dynamic effects and special effects.
Dynamic effects make fine adjustments to the original signal. These would be very familiar to most people as equalization or EQ, compression, limiting, gating, and other permutations of those same effects. Special Effects would be those of reverb, delay, echo, etc. These Special Effects usually add something that was not there originally.
In either case, you should use them as sparingly as possible. With today's audio equipment, good sound starts at the beginning source, and should be gently nudged to accomodate the peculiarities of the room. Since every room is different, there are no hard and fast rules. Rather, listen and use your ears. Does the signal sound natural? Can you understand the speaker? These should be your guidelines. The larger the room, the less reverb I would put on the worship leader since most large rooms have a long decay time anyway.
Sound for churches and all Houses of Worship present unique challenges. Many times there is a tug of war between the musicians and the spoken word, as these wonderful spaces designed to inspire, but not always be friendly to audio.
If you are in Central Florida (comprising the area around route I4 from Tampa to Daytona, and the counties of Orange, Osceola, Polk, Lake, Seminole, Volusia, Brevard, and Flagler) and in need of help? Then please send us a note, we'd love to get in touch with you. Proaudionet Consulting can provide all services to fix your audio problems. We specialize in coming in 'after-the-fact' and revising existing systems. Additionally, we can train your staff in how to properly maintain your system.
We hope to hear from you, and have a wonderful day!
Sound effects can be broken down into 2 basic categories, dynamic effects and special effects.
Dynamic effects make fine adjustments to the original signal. These would be very familiar to most people as equalization or EQ, compression, limiting, gating, and other permutations of those same effects. Special Effects would be those of reverb, delay, echo, etc. These Special Effects usually add something that was not there originally.
In either case, you should use them as sparingly as possible. With today's audio equipment, good sound starts at the beginning source, and should be gently nudged to accomodate the peculiarities of the room. Since every room is different, there are no hard and fast rules. Rather, listen and use your ears. Does the signal sound natural? Can you understand the speaker? These should be your guidelines. The larger the room, the less reverb I would put on the worship leader since most large rooms have a long decay time anyway.
Sound for churches and all Houses of Worship present unique challenges. Many times there is a tug of war between the musicians and the spoken word, as these wonderful spaces designed to inspire, but not always be friendly to audio.
If you are in Central Florida (comprising the area around route I4 from Tampa to Daytona, and the counties of Orange, Osceola, Polk, Lake, Seminole, Volusia, Brevard, and Flagler) and in need of help? Then please send us a note, we'd love to get in touch with you. Proaudionet Consulting can provide all services to fix your audio problems. We specialize in coming in 'after-the-fact' and revising existing systems. Additionally, we can train your staff in how to properly maintain your system.
We hope to hear from you, and have a wonderful day!
What is a House of Worship?
Traditionally, a House of Worship meant some large building that house hundreds of people. Yet today, that has changed drastically. There is everything from traveling churches that rent school auditoriums, to the mega-church that houses thousands. We find Houses of Worship in storefronts, homes, and even outdoor drive-in churches. We feel that anywhere that people come together in joint praise and reverence constitutes a House of Worship. It could be as few people as two... or even one.
Understanding the audio needs for the all of these varied venues requires experience and innovation. Many times there is a tug of war between the musicians and the spoken word, as these wonderful spaces designed to inspire, but not always be friendly to audio.
We at Proaudionet Consulting understand these challenges and are prepared to help get the right message out to the congregation. Our philosophy is that the spoken word is the most important requirement in a House of Worship, as the spoken word carries the message.
If you are in Central Florida (comprising the area around route I4 from Tampa to Daytona, and the counties of Orange, Osceola, Polk, Lake, Seminole, Volusia, Brevard, and Flagler) and in need of help? Then please send us a note, we'd love to get in touch with you. Proaudionet Consulting can provide all services to fix your audio problems. We specialize in coming in 'after-the-fact' and revising existing systems. Additionally, we can train your staff in how to properly maintain your system.
We hope to hear from you, and have a wonderful day!
Understanding the audio needs for the all of these varied venues requires experience and innovation. Many times there is a tug of war between the musicians and the spoken word, as these wonderful spaces designed to inspire, but not always be friendly to audio.
We at Proaudionet Consulting understand these challenges and are prepared to help get the right message out to the congregation. Our philosophy is that the spoken word is the most important requirement in a House of Worship, as the spoken word carries the message.
If you are in Central Florida (comprising the area around route I4 from Tampa to Daytona, and the counties of Orange, Osceola, Polk, Lake, Seminole, Volusia, Brevard, and Flagler) and in need of help? Then please send us a note, we'd love to get in touch with you. Proaudionet Consulting can provide all services to fix your audio problems. We specialize in coming in 'after-the-fact' and revising existing systems. Additionally, we can train your staff in how to properly maintain your system.
We hope to hear from you, and have a wonderful day!
Subscribe to:
Posts (Atom)