The HIS System
The Highly Intelligible Sound System

A Possible Church Sound Performance Standard

Compiled and Written by Joseph De Buglio
a work in progress

Is a Church Sound Standard Possible? Yes

Who is it for? My Customers. It is a way for them and and any other church to express what quality of sound system performance that they want. It is a way of knowing how to get full use of their worship space and sound system. This is also a promise and commitment that when your church meets all of these needs your sound system and acoustics will not be standing in the way of someone from understanding the Word of God.

Can other churches use it?
Yes.

Why did you write this standard?
I initially wrote it from myself. It is what I expect when I go to church. It is written for they layman by a layman. I first wrote some of these ideas when I was building churches. After working on 3 churches as an apprentice framer and going to the church dedications, I could not understand what was being said. It made me mad enough to do something about it. That was 30 years ago and over 1000 church projects.

How did you come up with the standard?
It is a combination of all of what churches have asked for over the years and the constant request to know how to tell of a good sound system from a bad one. It also came out of studying how churches were actually using their sound systems, and matching it up to the best laws of physic of how churches used audio equipment. It also accounts for the limitations of audio equipment and loudspeakers. In all of this, I also learned a simple truth - a sound system can only perform as good as the room lets it. If you have a "Properly Designed" sound system with speakers near or close to the spot they should be in and you are having problems and everything is connected and is adjust as well as it can be, more technology is not really go to make that much more of a difference - even with an unlimited budget. Bottom line is, the room must be changed. Until then, you will always be struggling.

How many churches have you based your standard on?
When I first introduced the standard, it was based on around 40 churches in 1982. As I work on or studies more churches, I refined the standard. Now it is based on over 800 churches. Yes, that means that there are over 800 churches that have a sound system and acoustics that I designed that passes the HIS System Standard or they have a sound system and acoustical design that will get their church to pass the HIS System standard or they have a sound system that someone else designed that passes the HIS System standard. There are a number of great sound engineers out there that are doing amazing work and while some of them don't support this standard their work does.

Can this standard apply to all churches?
Yes. This standard is largely based on performance and what it take for human to human contact. For example....

  • It is natural to look at what you hear. So the sound system should encourage you to look at the stage, altar, minister, priest or performer when working at the front of the church. The sound should not be coming from the sides or behind you.
  • You need a minimum of 92% intelligibility everywhere in the room when using the old fashion and most reliable Bell Telephone live speech test.
  • You need to be able to stands at a comfortable distance from a microphone and for the sound system to broadcast your voice across the room. Usually that is about 18 to 24 inches.
  • You need a sound system stable enough to have up to 10 microphones open at the same time without feedback.

The standard below covers all of these and more. These are all universal requirements that just about every church needs.

The standard also addresses how people worship. Just about every congregation sings during worship. What does it take for good congregational singing? How can the sound system help? What condition does the room have to be in?

What about the growth in contemporary music programs? It seems that this standard was written long before that trend.
Was it? In 1986 I worked with a church in Baton Rouge, LA. It seating 6500. It had 3 rear projection screens, 24 performers and musicians, a 56 channel mixer, and they were singing to Hillsong before Hillsong became popular 15 year later. The only difference between then and now is that smaller and smaller churches are recognizing that this is now an acceptable way of worship. The HIS Systems Standard was applied to that church back then an it applies to modern worship styles today. This is because it is based on performance standard, not what equipment can do.

Does newer technology and digital equipment put off the need to fix the acoustics of a church?
NO!
What it is doing is occasionally adding a minor level of performance gain in one area, some performance loss in another and a lot of false hope. In the end, it is postponing fixing the room for years. New technology works so much better in a good room that many can only dream of the results.

When a church calls me in to look at what they have, one of the first things I do is I do a quick evaluation test as found on this website. (the links are below.) None of the churches that have contacted me so far had a room or a sound system that could pass even 50% of the HIS System Standard or score more than 40% of the evaluation test. After testing the room, I share with the church the results and explain that who ever they finally hire, that the new sound system and worship space should be brought up to at least meet all of the hearing requirements. The good news is that most seasoned sound system experts are not only able to bring the sound system up to HIS System Standard but exceed them if the acoustics gets fixed at the same time. Often fixing the sound system is not enough. If it was, then most churches would be upgrading their sound system using the same design - but that is not what is happening. If you keep changing the sound system design every time you upgrade your sound system, you have a serious room problem that must be fixed first before you will see any sound system performance improvement.

The HIS System Standard is performance based, not equipment based. This is meant to be written so that any church can afford acoustics and a sound system that will meet their needs. It is our hope that the information provided below will help you church get the sound system they need, not what someone wants to sell you.

Is the HIS System Standard Perfect? No
Is the HIS System Standard absolute? No
Is the HIS System supported by the secular community such AES, NSCA or other professional organizations? Not yet.

This standard is written for churches, lay people, church board members and church sound operators. Yes, there are much better ways to write this standard but I think that if and when the Pro Audio community gets around to it, the average lay person on a church board will get overwhelmed with the technical jargon. Unit then, I intend to keep using this standard for my customers. After all, you're asking for it right now if you have read it this far!

If your church sound system performs as good or better than these standards, please let us know about it. If you have any comments or suggestions about the Standard, please send us an email jdb@jdbsound.com


Setting a Standard


The HIS System Standard has been based on the following goals:

  • 1. Each standard must be applicable to over 90% of the churches within the church community
  • 2. To have a foundation of a sound system to build upon for future growth
  • 3. The system should have all of the basic features designed into the system, ready to provide sound for all of the most common church events from worship to weddings, to funerals to concerts to drama.
  • 4. It must use combinations of equipment, microphones and speakers relatively noise free when inserted into the system.
  • 5. The combinations of products have to be affordable.
  • 6. It must satisfy people with average hearing lose and benefit those with hearing aids. It shall be understood that a hearing assist system is needed for those whom you have to raise your voice to in normal conversation.
  • 7. Easy to operate with the least amount of instruction.
  • 8. Have enough gain so that a person can stand in a comfortable position with a fixed microphone on a stand. This generally required a micing distance of 18 inches. (This is only for a single open mic for speaking. Adding more open mics will lower the working distance according.)
The HIS System also require certain acoustical consideration. People have been trying many sound system designs to avoid dealing with the acoustics of a space. The records shows failures than successes. Until recently, many people thought that an audio system could sidestep the laws of physics. This is not the case. Here are the acoustical conditions that are needed to get you the best performance of a sound system.
  • The room has to be free of echo's.
  • The room has to be free of flutter echo's
  • The RT60 for most churches works best between 1.4 to 1.7 seconds flat from 200 to 4000 hertz.
  • The RT60 should not be less than 1.3 seconds.
  • The RT60 should not exceed - on average 1.9 seconds (This is mostly for Traditional worship and cathedral spaces.)
  • There should be no standing waves from any angle. (That is from side to side, front to back and floor to ceiling.)
  • The NC of the room shall be below 40dB
  • The room should have an average signal to noise ratio of 25dB throughout the seating area and stage area (for churches that have aggressive music programs.)
It is generally understood that each violation of these acoustical conditions will limit the performance of the sound system in proportion to how serious the acoustical problem are.

The Basic Minimum Performance Standards or Requirement


Speech requirements of a single open microphone at a pulpit, lectern or as a hand held mic.

  1. Average working distance from a single regular dynamic microphone (such as a Shure SM58 or better) before feedback -18 inches. (In a room with NC 40 or lower)
  2. Maximum working distance from a regular dynamic microphone (such as a Shure SM58 or better) before feedback - 30 inches (In a room with NC 40 or lower)
  3. Average sound pressure coverage within the seating area +/- 3dB
  4. Intelligibility score +/- 2% of 92% in all seats with either oral speech testing, %alcons or STI or RASTI equivalent. (A Computer is option as the oral speech test is much more accurate.)
  5. When eyes are closed, turn your head to the source of the amplified sound. When you open your eyes, you should be looking at the person speaking or in their direction from any location within the sanctuary.
  6. At 18 inches from the mic, have enough sound pressure level (SPL) to have a ratio difference of 20 to 25dB signal to noise. That is for the audience to hear direct clear sound 20 to 25dB above the room noise or, to have an average SPL of 68dB in all of the seating. (This is best achieved with an NC of 40 throughout the seating area and on stage/altar area.)
  7. To have a sound system that does not increase the reverberation time of the room.
  8. To have a sound system that does not degrade the performance of the Organ or competes with congregational singing when a microphone is left on.
  9. To have a sound system in which the sound operator can quickly change the controls without people in the audience noticing the changes.
  10. To have a sound system that will not introduce a signal or noise when using the maximum mic gain for a single open microphone. (that means no hissssss or radio stations)

Music Requirements when many microphone are open.
  1. Have a sound system that is stable with 3 mics open and micing at 10 to 16 inches without feedback.
  2. To have a sound system that will not introduce a signal or noise when using 4 mic open and micing at 10 to 16 inches without feedback. (that also means no mixer hissssss)
  3. Have enough SPL in the sound system and without distortion so that a person can be heard clearly when needing to speak to the audience during congregational singing.
  4. To begin the design of the speaker system as a point source system*** (speaker front and center ahead of a central pulpit) and modified accordingly as the Architecture permits of a sanctuary for the highest level of speech intelligibility and best coverage. (Music playback systems that have a Left and Right point sources much like Home HIFI and Recording Studios and can be combined as LCR systems when budgets permit. Churches on limited budgets are best served with mono point source designs when the roof heights permit it.) (*** A Speaker system should never attract attention unto itself. The speaker system should always attract you to the main position a minister normally speaks from. It is important for the sound system to mimic natural communication in which we look at what we here during the sermon portion of any worship service. When this is not possible, you should get help.)
  5. All microphone lines shall be balanced type II (Two conductors, a ground wire and tin foil shield) using a 3 pin connector.
  6. All lines shall be wired - Pin 1 ground, Pin 2 Hot signal or positive signal (Red or White wire), Pin 3 cold or negative signal (Black).
  7. All microphone lines shall be continuous from the platform to the mixer position without any breaks. (Multi pair cables have a high failure rate. If you have to use a multi pair cable or snakes make sure the mic pairs that are individually jacketed)
  8. ** Clean wind screens weekly of all microphones. Ask your product manufacturer how to do that.

To do old school tests of most of these standards without test equipment, please refer to the following web pages.
http://www.jdbsound.com/art/eval1.htm
http://www.jdbsound.com/art/eval2.htm
http://www.jdbsound.com/art/eval3.htm


Recommended Needs and Wants

These are basic guidelines only. A well designed sound system will fall within most or all of these suggestions.
  1. Provide a minimum of 1 mic input for every 60 square feet of the pulpit/ platform/ altar area. This will ensure enough mic locations for the choir and all special events. (Churches with more ambition music programs should use 1 input for 45 square ft as a minimum.)

  2. Provide an amplifier that has a minimum of 1/2 watt* per person** for speech only system. (Churches with music programs should have a minimum of 2 to 10 watts per person)
    (* Watts per person are just guidelines to ensure that the speaker systems are not being under powered. Under powered systems tend to have higher failure rates and have higher levels of distortion. Distortion degrades speech intelligibility. Speakers with higher efficiencies should allow you to use less power per person. Adjust your system power requirements accordingly. While a sound system should not be designed based on watts per person, when looking a proposal for system evaluations, it is a quick indicator whether to red flag the project or not.
    **
    Power standards are based on a loudspeaker 99dB 1 watt 1 meter with a coverage pattern of 40 x 90. up to approximately 90ft when acoustical conditions allow it.)
  3. Provide a tape player and / or CD/MP3/Digital/computer player for playback of singing events.
  4. Provide a separate tape recorder/computer/MP3 unit for recording of services. (This prevents feedback loop which often destroy sound systems.) (Many churches use tape sales to funding other sound system expenses) (Update - this is also true for computers. Never have the input and output of a computer connected at the same time to a mixer if your using a computer to record with)
  5. Provide a Constant "Q" 1/3rd octave analog or digital equalizer for every live mix. Mains, floor monitor, choir monitor....
  6. Provide the option for floor monitors without replacing the mixer.
  7. Provide the option for choir monitors without replacing the mixer.
  8. Provide the option for separate signals from the mixer for Tape Recording, Distributed System (Nursery, offices, washrooms...) Broadcast output for TV, cable or video, and Hearing Impaired Systems.
  9. Pre Fade Listening PFL is a must on all church sound system mixers.
  10. Mixer must provide 48 volt phantom power for condenser microphones which use an electric current to increase the performance of the microphone.
  11. Mixer, Amplifier and Equalizer/Processors/Speaker managers should always be separate units. (Amplifiers with built in DSP's could be used.) (There are some digital mixer than have enough output processing that you can go from the mixer to the amps direct.)
  12. All Unbalanced Consumer products with -10dB inputs and outputs such as CD players, Computers, tape players and recorders should be within 25ft of the mixer.
  13. Unbalanced line level signal lines should use passive or active direct boxes to convert to mic level signals when sending a signal from the altar/stage area to a mixer when the signal is bundled in a snake or bundle of shielded mic lines.
  14. All live sound professional component shall have electronically balanced or transformer balanced inputs and output - ie mixers, digital processors, equalizers, amplifiers, digital delays, and other professional live sound gear.
  15. All Mixers for a mono church system should have separate Left and Right (Live and Record) master output faders when only a single mixer is used to manage FOH and Recording of worship programming.




The following books were an asset in confirming if these standards were a reasonable level of common performance expectation in a church setting.
  1. Phillip Giddings, Audio System Design and Installation (SAMS, Indiana, 1990)

  2. Don, and Carolyn Davis, Sound System Engineering. Howard W. Sams & Co., Indianapolis, IN 1987

  3. The Complete Handbook of Public Address Sound Systems, F. Alton Everest, Tab Books, Blue Ridge Summit, PA 1978

  4. David Egan, Architectural Acoustics, McGraw Hill, 1988

  5. Handbook for Sound Engineers, 2nd edition, Glen M. Ballou, ed. Howard W. Sams, 1991


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Copyright © 1982-2010
Originally written in 1982 and revised in 1986, 89, 91, 96, 99, 2001, 2005, 2006, 2007, 2009, 2010
This Standard is updated as professional experts and the church community contribute and respond to the effectiveness of this documents.
This document is for the church community and it is not meant to replace expert help from professionals.
All articles on this website are works in progress. Any spelling and grammatical errors will be corrected as you point them out or when time permits.