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[frank kayser]

Hi Folks,
People are showing up for live music again, and surprise, the question of "too loud" is back in the forefront.


My question regards the "A" weighting scale - and its reflection of the normal human frequency sensitivity.


The statement goes like this:
Since the ear is more sensitive to the mid-high frequencies, that as long as those frequencies remain "in check" that one can boost low frequency punch (SPL) and not damage hearing (as much/as fast).


I disagree both on an aesthetic level, and on my understanding of the problem.  Some mix much more bass heavy (and should, depending on the genre) in genres that that the thump-in-the-chest sub is foreign to the style, thus inappropriate.  This is trying to fatten up the mix because there's "room over the "A" curve at those frequencies". 


I maintain 100dB at 50hz can do just as much damage as 100dB at 1Khz or 3khz.  The damage is there, but much more noticeable in the high frequencies as those are where the voice lives. We need those frequencies for daily life. For that reason, I *believe* the "C" or "unweighted" scales are a truer representative of damaging sound pressure levels.


I'm somewhat at odds with OSHA and NIOSH regarding the "A" vs "Unweighted" scale argument.


Your take?
frank

[Geoff Doane]

My take?  In order of significance:

If somebody doesn't like the music, it's "Too loud".

If the mix isn't very good, or bad acoustic make vocals unintelligible, it's also "Too loud".

Finally, there are probably some times when it really is too loud; the system is audibly distorted, or it's causing physical pain to the audience.  I'm pretty sure I don't fall into that category.

Fortunately, I haven't had much trouble in this department since things have started up again.  Audiences are generally happy to see live music again.  I seem to have more trouble with getting enough gain before feedback with quiet performers than too much volume.

There was once complaint this summer, at an outdoor gig with a 13-piece R&B band.  The complainant was a volunteer at the venue (a Victorian Botanical Garden), who insisted that the bad was much too loud and I had to "turn things down immediately."  I looked around and saw a lot of smiling faces, little kids dancing on the grass, and nobody with their hands over their ears.  I told him I'd see what I could do, and then kept on doing what I was doing.

GTD

[Scott Bolt]

Hi Folks,
People are showing up for live music again, and surprise, the question of "too loud" is back in the forefront.


My question regards the "A" weighting scale - and its reflection of the normal human frequency sensitivity.


The statement goes like this:
Since the ear is more sensitive to the mid-high frequencies, that as long as those frequencies remain "in check" that one can boost low frequency punch (SPL) and not damage hearing (as much/as fast).


I disagree both on an aesthetic level, and on my understanding of the problem.  Some mix much more bass heavy (and should, depending on the genre) in genres that that the thump-in-the-chest sub is foreign to the style, thus inappropriate.  This is trying to fatten up the mix because there's "room over the "A" curve at those frequencies". 


I maintain 100dB at 50hz can do just as much damage as 100dB at 1Khz or 3khz.  The damage is there, but much more noticeable in the high frequencies as those are where the voice lives. We need those frequencies for daily life. For that reason, I *believe* the "C" or "unweighted" scales are a truer representative of damaging sound pressure levels.


I'm somewhat at odds with OSHA and NIOSH regarding the "A" vs "Unweighted" scale argument.


Your take?
frank

• If you are playing in a venue that doesn't actually want music (like an eagles club), it will always be too loud no matter what you play or how loud you play it
• The A weighting is for hearing damage in specific.  Lower frequencies can damage your hearing; however, they require much higher levels to do it than HF
• Good speakers and good mixing provide a pleasing sound that people will want to hear "loud" much more than poor speakers and poor mixing.  Pleasent music is always better tolerated at higher volumes than unpleasent music (regardless of what is making it "unpleasent"
• Loud stage noise (particularly drum cymbals, snare, and guitar) can drive an adience away regardless of how great a PA you have.
• Crap monitors can fill up the space with crap sound AND cause feedback.  The greatest FOH speakers will not make up for this situation.

If you are having issues with GBF, I suspect you have a monitoring issue and stage volume issues.  Look there first, then work on the FOH.

[Matthias McCready]

This document is long, but it is a good read, and is quite enlightening.

[Steve-White]

This document is long, but it is a good read, and is quite enlightening.

Good stuff.

[Mike Caldwell]

Very good read. I liked that they actually acknowledge what we have to deal with many times
and what is and is not with in our control.
The section on venue acoustics for the given type of performance should be required reading for many promoters.

At construction sites I'm still amazed by the number of people I see running chop saws cutting tile, brick, steel, ect. and operating pneumatic tools with no hearing protection.

[frank kayser]

As always, folks, thanks for good food for thought.


frank

[Michael Lawrence]

Frank,

the WHO Safe Listening Venues standard linked above was based in part on some research I co-authored on the topic, although I didn't have direct involvement in the WHO standard and I don't think it's a "home run" it's certainly a major step in the right direction. For a more detailed look at the research I recommend this AES Technical Document on understanding and managing sound exposure and noise pollution (the paper is in the context of outdoor events but the information is applicable regardless).

https://www.aes.org/technical/documents/AESTD1007_1_20_05.pdf

If you have not reviewed Appendix A of the WHO Safe Listening Devices document, I recommend doing so. It explains the basis of the NIOSH dosimeter measurements such as we have integrated in to Smaart, and the audiological basis for using the A-Weighting curve for sound exposure assessment. It has little to do with perceived loudness contours, and much to do with being a good statistical match for observed NIHL.

https://www.who.int/publications/i/item/9789241515276

As discussed in the technical document, low frequencies can indeed be damaging to hearing, but at higher levels, and this is a newer and less-studied phenomenon. For typical situations with typical energy distribution (popular styles of music, for example) the A-Weighted NIOSH exposure measurement can be demonstrated to be a statistically good predictor of NIHL risk.

The research is ongoing - the existence of an environment where an individual (concertgoer) is subjected to extremely high levels of LF is a relatively recent thing compared to the bulk of audiological data available on NIHL.

https://www.cdc.gov/niosh/docs/98-126/default.html

However many European countries have acknowledge the LF exposure hazard and have implemented a secondary limit of Peak C, commonly 135 or 140 dB, as part of their health and safety regulations. It is not uncommon for Peak values in the low 130's to be encountered at FOH for typical live music program material.

Statistically in such a case we can expect a Peak C value to be about 32 - 35 dB above the average (L50) A-Weighted levels. The AES Technical document includes some guidance on observing the difference between the C and A-Weighted levels as a potential indicator to evaluate excess LF hazard that is not well characterized by the A Weighted dosimeters. This is one of the reasons we added a "C-A" weighting option for Leq metrics in Smaart as of v8.5.

[Steve-White]

The outcome of this should be interesting.  As a result of "DJ's" (and bands in some cases) being clueless over the years and playing at levels beyond what the conditions warranted or their equipment could properly produce/re-produce, many venue's have implemented "noise restrictions" which I have read are in many cases established at 90 dB maximum.  Some even have sound pressure monitoring equipment installed that will flash a red light if a preset level is exceeded.

IN many cases the venue's themselves are as clueless as the offensive noise makers.

https://www.youtube.com/watch?v=t6BxbuiKpU8

[Tim McCulloch]

The outcome of this should be interesting.  As a result of "DJ's" (and bands in some cases) being clueless over the years and playing at levels beyond what the conditions warranted or their equipment could properly produce/re-produce, many venue's have implemented "noise restrictions" which I have read are in many cases established at 90 dB maximum.  Some even have sound pressure monitoring equipment installed that will flash a red light if a preset level is exceeded.

IN many cases the venue's themselves are as clueless as the offensive noise makers.

https://www.youtube.com/watch?v=t6BxbuiKpU8

I didn't watch the video yet, but most small venues implement policies and equipment in misguided pursuit of simple answers and solutions.

The problem is things are too damn loud for the venue, either objectively or subjectively.  The use of SPL data, no matter how scaled or collected, is an attempt to make objective that which is also subjective, i.e. if you don't like the music, it's always too loud.

As I used to explain to bar bands, the licenses on the walls are not there for "you to pimp your 'art', the licenses permit the bar to put liquor in a glass, maybe sell some food, and hopefully make a profit."  If a band performs or behaves in ways that interfere with that revenue generation they are sabotaging return bookings.

[ProSoundWeb Community]