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?
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
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
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?
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
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 firstname.lastname@example.org
Setting a Standard
The HIS System Standard has been based on the following goals:
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.
- 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.)
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 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.)
The Basic Minimum Performance Standards or Requirement
Speech requirements of a single open microphone at a pulpit, lectern or
as a hand held mic.
- 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)
- 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)
- Average sound pressure coverage within the seating area +/- 3dB
- 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.)
- 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.
- 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.)
- To have a sound system that does not increase the reverberation time of
- 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.
- To have a sound system in which the sound operator can quickly change the
controls without people in the audience noticing the changes.
- 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.
- Have a sound system that is stable with 3 mics open and micing at 10 to
16 inches without feedback.
- 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)
- 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
- 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.)
- All microphone lines shall be balanced type II (Two conductors, a ground
wire and tin foil shield) using a 3 pin connector.
- 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).
- 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)
- ** 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.
Recommended Needs and Wants
These are basic guidelines only. A well designed sound system will fall
within most or all of these suggestions.
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.)
- 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.)
- Provide a tape player and / or CD/MP3/Digital/computer player for playback
of singing events.
- 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)
- Provide a Constant "Q" 1/3rd octave analog or digital equalizer
for every live mix. Mains, floor monitor, choir monitor....
- Provide the option for floor monitors without replacing the mixer.
- Provide the option for choir monitors without replacing the mixer.
- 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.
- Pre Fade Listening PFL is a must on all church sound system mixers.
- Mixer must provide 48 volt phantom power for condenser microphones which
use an electric current to increase the performance of the microphone.
- 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.)
- 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.
- 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
- 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
- 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.