Tuesday, March 06, 2007

Volume in Worship

Last night at a congregational meeting a concern was voiced in regard to volume in worship services at Parkview. In response to this comment I felt it would be prudent to discuss the issue in a few posts over the next several weeks. One thing for sure, there are a lot of passionate and diverse opinions about what makes a good church sound mix. Usually when the issue is discussed among the average church atttender (i.e. non musician) the comments typically refer to volume. The unknown reality is that getting a pleasing and engaging sound mix is much more complex than simply managing volumes. Sometimes a louder decibel (sound intensity measurement) mix can sound very pleasing and warm. Other times a softer decibel mix can sound too loud and harsh. Though I am not a expert in this arena, I will address a few “less technical” issues that come into play when discussing the general issue of sound reinforcement in a church worship space. If any of you have links to relevant articles or posts from more technically qualified sources, please send them to me and I will consider linking to them.

It is helpful when discussing sound volume to understand how volume or loudness is measured. The term decibel is the scientific measurement for determining the loudness and softness of sound. Below are a few measurements I pulled from the Galen Carol Audio web site (I believe these are dB A scale measurements). You can see the complete list here.
ENVIRONMENTAL NOISE

Normal Conversation – 60-70 dB
City Traffic (inside car) – 80 dB
Train Whistle at 500’ – 90 dB
Power Mower – 107 dB
Pain Begins – 125 dB
Jet Engine at 100 feet – 140 dB
Loudest Sound Possible - 194 dB

SOUND LEVELS OF MUSIC

Normal Piano Practice – 60-70 dB
Loud Singer at 3’ – 70 dB
Chamber Music in Small Auditorium – 75-85 dB
Loud Piano – 84-103 dB
Symphonic Music Peak – 120-137 dB
Rock Music Peak – 150 dB

OSHA DAILY PERMISSIBLE STANDARDS

8 hours @ 90 dB
4 hours @ 95 dB
2 hours @ 100 dB
1 hour @ 105 dB
.25 or less hours @ 115 dB
At Parkview we typically peak at around 90-92 dB (95 dB when we have a horn section). If any of you reading attend other churches, I’d be interested in knowing what is typical for your worship service.

Please check back for additional posts on this topic. Also, if you are leaving a comment, please observe the “comments policy” by keeping your comments respectful of the various opinions represented on this topic.

9 comments:

Jim C said...

Scott,

The church I help out with in Cedar Rapids holds at about 90dB for most services. Interestingly enough, when the brass ensemble or the organ plays, it is considerably more (~ +5dB at the back of the room, which is significant because the brass and organ do not use microphones - which means its louder than that at the front of the room).

The room size is about 1/2 to 1/3 the size of Parkview's main auditorium.

Jim

Jim C said...

Just a follow up... I checked with a friend of mine who until just recently was the worship pastor at a very large contemporary church in Minneapolis. He said they aimed to average at 90dB at their church.

Jim

scooterpastor said...

Not to muddle the conversation, but it would also be interesting to see what churches are doing on the C-scale, since that tends to represent non-audible frequencies that give you that low end feeling to sound.

First Theology said...

I say this with all grace and respect to those who might disagree...

Complaints of excessive volume are often a smoke-screen for a deeper dissatisfaction about style (whether that exchange is conscious or unconscious). As your data indicates more traditional styles accompanied by brass players are often perform at higher decibels than the mix of more "rock band" styles, yet typically the traditional styles are tolerated as volume-appropriate and the rockin’ styles are tolerated as volume-excessive.

Into this confusion I appreciate you educating us concerning the tech specs of exactly what the volumes various stuff produces. That helps make the discussion a bit more objective (you are right that the c-scale rumble probably needs to be taken into account too).

All in all this kind of critical/constructive feedback sounds suspiciously like what we had at my last church concerning "excellence." The party-line said: "We are going to only do music with the utmost excellence." Excellence ended getting defined not by technique or precision, rather by style – i.e. some styles were not in-and-of themselves were not considered excellent (so another smoke-screen). Pragmatically unclear verbiage was used to critique and prohibit unwanted styles. Since then I’ve been pretty sensitive to that approach to control style.

So hopefully I don't sound too reactionary! I just think we need to make sure we ask for definition & nuance about terms like "excellence" or in this case "volume."

scooterpastor said...

Josh. Thanks for your very gracious thoughts on the issue. You certainly have a unique and helpful perspective in light of your recent experiences in another church.

Because (for example) a symphony orchestra significantly surpasses our volume levels, it certainly leads me to question if the issue is as much about style as it is loudness.

Anonymous said...

I can see where mixing all the sounds could be hard...I'm glad it's not my job :)

Could it also maybe sound louder not just because of the size of the auditorium, but maybe even the shape of the room, structures in the room, building materials used in the room, etc? Something to be aware of when the time comes for the new auditorium (which I'm sure it has already been mentioned).

I usually don't have too much problem with the volume, but sometimes more with certain instruments drowning out voices or other instruments. Again it's a mix issue.

-Jen Essington

Jim C said...

Jen makes a wonderful point... "I usually don't have too much problem with the volume, but sometimes more with certain instruments drowning out voices or other instruments. Again it's a mix issue." I think this is probably more the issues (tied in also with what Josh was saying about stylistic preferences).

I think its fair to say that people confuse the concept of "volume" with that of "loudness" and "balance". They are in of themselves different beasts.

If something is not pleasing to your ear, is it because its too loud? Or is it because its not balanced (well mixed - this is the balance of the instruments) or is it because of a lack of faithful reproduction (unequal loudness - this is the EQ curve/response of the room and speaker array)?

It is a strange concept to some people to suggest that BIGGER speakers and a slight increase in volume can actually sound "less loud" to people.

Want to see for yourself? Take your iPod and plug in the headphones. Turn to your favorite song and crank the volume up, but DON'T put the headphones on. Leave them on your desk.

Now take the same song and play it through your computer speakers at a moderate volume.

Now your home stereo at a moderate volume.

The most likely perception is that the headphone mix from the iPod is harsh and "too loud" even though in reality it is FAR quieter than either of the other two.

The computer mix may sound "ok", but on most home computers will tend to emphasize too much of the midrange instruments (snare drum, electric guitar, brass instruments).

In both of those cases, you are also introducing a significant amount of audible distortion because the system simply cannot handle the frequency response necessary to faithfully reproduce the music at a reasonable volume.

Your home stereo on the other hand will be the largest wattage (highest power) and have the largest speaker array (assuming the typical home stereo). I would venture to guess that most people could comfortably listen to the same song at 2 to 3 times the dB level of what the iPod had tried to reproduce, yet because its a more "balanced" sound, they will claim it to be less harsh and more pleasing to the ear.

"Now Jim, obviously cranking your iPod headphones causes distortion and that has nothing to do with a PA system in a big room!"... oh, but it does... magnify the situation 300 times. If a speaker system in a room is undersized for the necessary frequency range needing to be reproduced you wind up with a very similar type of distortion as attempting to use iPod headphones as desktop speakers. The physical speaker drivers simply cannot cleanly perform that task.

I'll add to why this is important when I get the chance :)

Jim

Brian Bailey said...

Scott,

Good topic! You wrote that "a symphony orchestra significantly surpasses our volume levels." I think it would be more accurate to say that that is true *at times*. The nature of most orchestral writing is that there is a very wide db range, and the big climaxes involving brass, percussion, etc. last no more than a minute or two. I think that would be the "orchestral music peak" that you cite as being 120-137. Even that will depend on the hall and one's location in the hall, of course. I don't think I've ever heard an orchestra that was so loud as to be painful for any length of time. But I still wouldn't want to be the wind players or whoever is sitting just in front of the brass section!

I'm glad you posted the OSHA standards. Hearing loss from high decibels is very real, and cannot be reversed. I have an article in my files that lists decibel levels of different situations and what the safe exposure time is (before potential hearing loss) if one is not wearing hearing protection. That article (which is not mainly about music, so doesn't seem to carry any bias about style) lists a "Rock concert" as being 120 decibels, and gives the safe exposure time as 7.5 minutes. Now you guys are responsible about this, I can tell, and you list your decibel peak as being in the 90s. But I think the sad fact is that some churches and Christian bands here and there aren't taking that into account.

As kind of an aside, I know a retired professor of organ who has major hearing loss in his left ear, because he would teach lessons all day sitting on the student's left, right up against the organ case. If he had just insisted that students play with a reduced registration through most of their lessons, his ears would be fine.

--Brian

scooterpastor said...

Jim, your illustration is great and it does clarify the issue of how a nicer system will sounder warmer and "less loud" at a higher volume than a poorer system at the same of even reduced volume level. I think this is often the issue in many churches.

Brian, you are right on. The orchestra comment I made was referring to peaks only. Recently John told me that at Chicago Symphony Orchestra concerts they make ear plugs available because of the higher decibel peaks, so it definitely is an issue.

The point being that whether it is a organ or a church band or a brass ensemble or whatever, we must take care to preserve the hearing of all people. To say we don't care about peoples hearing is totally wrong and I agree that some Christian concerts are way out of line by amplifying to dangerous volume levels.