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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB: The Classic Live Audio Board => Topic started by: Jay Brett on December 12, 2016, 01:21:57 PM
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I'd like to get some opinions on standard FOH DB restrictions. I'm going from a smaller Meyer PA where I didn't really need to enforce a DB/SPL limit to a new D&B rig that can easily outperform the Meyer rig. I'm in a downtown outdoor environment and we have brand new high-end residential towers just outside of the venue.
I see a ton of artist riders, but not many venue tech packs as I've been off the road and at this same venue for 4 years now. It seems like I use to see 105Dba at FOH on the regular.
What does everyone recommend? 105, 100 ??? A,C weighted?
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I would say it depends on the length of the show. You can go louder for shorter. Quieter for longer.
I'd go with NIOSH or OSHA limits.
A weighted, when weighing SPL that damages human hearing, C gives unrealistic answers.
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Technically, A weighting should never be used above 80dB.
C can give high numbers if people are used to using A.
Basically it depends on what you can get away with.
On a city street, lots of vibrations can get into buildings through the structure.
So they may not be able to "hear" it, but they can feel it.
It is also not only the scale, but also the response time. Slow and fast can give a wider or narrower range.
At one recent EDM show I did, the difference between A slow and C peak was 32dB.
HOWEVER-when you look at the difference below 100Hz to above 200Hz, the difference was around 42dB.
So-once again- a simple single number does not give an accurate easy answer.
So-it depends---------------
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When I'm mixing on my rig I max out at 105 dbC and don't get any complaints. This weekend the BE ran at 112 dbC and I had to leave the room periodically. Staff was telling me it was too loud as well and asked me to get it turned down.
But the crowd was into it and the system was clean so I didn't say anything to the BE.
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Technically, A weighting should never be used above 80dB.
Then why are NIOSH & OSHA using it and their charts don't start until 85dB?
https://www.cdc.gov/niosh/topics/noise/reducenoiseexposure/regsguidance.html
Yes I realize they are for a 8hr work day using loud equipment. Yes I know we assume no prior exposure during the day when we run shows. But its what we got.
If you metered things with C at a edm/rock concert you would absolutely be way higher on the meter than the only published source of spl restrictions we have. So to be inside the margin you would be forced to run things quite a bit quieter and the promoter/band might not be having you back.
Also, I'm not saying use the chart for peaks, I'm saying use it for an average level. If said concert is 1hr then the average level should be below 94dBA which is pretty easy given how much luls there are in music.
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So-it depends
You do know they're gonna put that on your tombstone, yeah?
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Then why are NIOSH & OSHA using it and their charts don't start until 85dB?
https://www.cdc.gov/niosh/topics/noise/reducenoiseexposure/regsguidance.html
OK, I was wrong. The upper limit for A is supposed to be 60dB, not 80dB.
Just because some people use it does not mean that it is proper or correct.
I was simply stating the level of the original intended curves were.
Here is some more reference if anybody is interested
http://www.acoustics.asn.au/conference_proceedings/AAS2013/papers/p39.pdf
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Technically, A weighting should never be used above 80dB.
C can give high numbers if people are used to using A.
Basically it depends on what you can get away with.
On a city street, lots of vibrations can get into buildings through the structure.
So they may not be able to "hear" it, but they can feel it.
It is also not only the scale, but also the response time. Slow and fast can give a wider or narrower range.
At one recent EDM show I did, the difference between A slow and C peak was 32dB.
HOWEVER-when you look at the difference below 100Hz to above 200Hz, the difference was around 42dB.
So-once again- a simple single number does not give an accurate easy answer.
So-it depends---------------
I've always been confused by people's choice of A or C weighting. "A" makes sense to me, considering I'm more worried about what people are hearing as opposed to getting truly scientific data. For example, I had a local guy who thinks he's an audio guy post something on social media after a show at my venue. The headliner actually brought their own PA for that show, but regardless he was posting on social media that the show was 137DB, even posting a picture of his phone app he says he calibrated in his studio. He was using C-weight and was about 16 feet from 8 SB1000's. Had he used A-weight, it would likely have been closer to 110 or lower, still too loud but fairly normal in regards to concert audio.
I'm wanting to find a good compromise where I can keep the SPL at a reasonable level while at the same time not restricting visiting engineers into a unrealistic set of rules. I'm not worried about system protection, as I'll have tons of headroom and the ability to clamp anyone down who may be pushing it too hard.
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I've always been confused by people's choice of A or C weighting. "A" makes sense to me, considering I'm more worried about what people are hearing as opposed to getting truly scientific data. For example, I had a local guy who thinks he's an audio guy post something on social media after a show at my venue. The headliner actually brought their own PA for that show, but regardless he was posting on social media that the show was 137DB, even posting a picture of his phone app he says he calibrated in his studio. He was using C-weight and was about 16 feet from 8 SB1000's. Had he used A-weight, it would likely have been closer to 110 or lower, still too loud but fairly normal in regards to concert audio.
I'm wanting to find a good compromise where I can keep the SPL at a reasonable level while at the same time not restricting visiting engineers into a unrealistic set of rules. I'm not worried about system protection, as I'll have tons of headroom and the ability to clamp anyone down who may be pushing it too hard.
You're trying to prevent problems with neighbors who have more political and monetary capital than your venue is willing to risk. Good luck, because if you fail the City Commission will have your Board reading a "nastygram" from a bunch of lawyers.
The easy answer is to use whatever SPL level was not objected to previously. If the old rig got no complaints at (arbitrary number for discussion) 95dBA, slow, then use that until you feel more adventurous and/or have a better feel for the neighbors attitude.
As far as BEs... most of them get it when you tell them about the SPL limit. A few will scoff and a few will ignore it and you. I've worked a restored historic theater with a 95dBA fast limit. The national acts simply ignore the theater director unless they're already performing that way... Others will do their best to accommodate the limit but they struggle.
The potential for over-limit use starts with booking. Ricky Lee Jones or the Man o' War tribute? 8)
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You're trying to prevent problems with neighbors who have more political and monetary capital than your venue is willing to risk. Good luck, because if you fail the City Commission will have your Board reading a "nastygram" from a bunch of lawyers.
The easy answer is to use whatever SPL level was not objected to previously. If the old rig got no complaints at (arbitrary number for discussion) 95dBA, slow, then use that until you feel more adventurous and/or have a better feel for the neighbors attitude.
As far as BEs... most of them get it when you tell them about the SPL limit. A few will scoff and a few will ignore it and you. I've worked a restored historic theater with a 95dBA fast limit. The national acts simply ignore the theater director unless they're already performing that way... Others will do their best to accommodate the limit but they struggle.
The potential for over-limit use starts with booking. Ricky Lee Jones or the Man o' War tribute? 8)
Well, the good thing is the company I work for owns everything around the venue, including the residential towers. So that makes life a little easier as I'm getting info directly from the source and we have to compromise between being respectful of tenants, but also making sure they understand they are moving into what's labeled as the "Midwest's #1 Entertainment District".
While I took measurements with the old PA, I never attempted to establish a SPL limit for multiple reasons. I do know the D&B rig I have coming can cruise at 115DB all day, as I've done the testing with it this summer.
I'm more dealing with whiners too, not really anything that can legally hold up. I've done testing during a concert and on the 22nd floor, the SPL would spike by 1-4 DB with the music, never getting past 62dbA in the unit's bedroom and living room.
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I'm more dealing with whiners too, not really anything that can legally hold up. I've done testing during a concert and on the 22nd floor, the SPL would spike by 1-4 DB with the music, never getting past 62dbA in the unit's bedroom and living room.
When you consider that normal conversation is around 65dB, that means that if you are trying to talk to somebody, then the outside music is as loud as you talking or an average TV listening level.
That can get QUITE annoying.
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I do know the D&B rig I have coming can cruise at 115DB all day, as I've done the testing with it this summer.
115dB A (slow or fast) is going to REALLY piss off a lot of people, and is quite painful.
115A peak (typically around 105dBA SLOW) is starting to push the pain level.
About the only way to "balance" that sort of level is with the subs running 125-130dB C.
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115dB A (slow or fast) is going to REALLY piss off a lot of people, and is quite painful.
115A peak (typically around 105dBA SLOW) is starting to push the pain level.
About the only way to "balance" that sort of level is with the subs running 125-130dB C.
Agreed, and this is why I'm likely going to have a SPL limit on the venue tech pack. Honestly, I'll probably only have to enforce it a few times a year with young BE's as I get mainly very experienced engineers... Just had Prince's guy here last week (amazing mix).
I just need something solid that I can bring up if a visiting BE isn't wanting to behave!
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Perhaps this is worth a read on the weighting thing. Frankly I find it hilarious to be given an A weighted dB limit at a festival, and then asked to cut 63Hz for the rest of the night because of complaints. Every. Single. Time.
https://www.merlijnvanveen.nl/en/study-hall/123-realistic-goals?utm_source=Merlijn+van+Veen+Newsletter&utm_campaign=3b9498ee43-Merlijn_van_Veen_Newsletter_December_2016_reminder&utm_medium=email&utm_term=0_76afddd1fc-3b9498ee43-74511173
Sent from my iPhone using Tapatalk
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To the OP - does your city have any ordinance or restrictions around festival/event SPL limits? In our city, they do and it's limited to 95dB at the edge of the venue grounds/area.
I realize that's a sketchy and potentially unenforceable policy, but you may want to check with the city to see what they have on the books.
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I was going to say that the city or venue usually dictates the rules. At a venue I manage the PA system for, I have set it so that even the best of engineers can only get about 115db C fast. The goal was to have them all sit around 105db C fast. For the most part that is where it sits. 105db C fast is plenty loud if you ask me.
I have always been under the schooling that anything over 100db fast or slow is too unrealistic for A weighting. If I want to argue my point to an enforcer, I show them the difference and they usually quiet down pretty quick. I have an RTA mic that can be used to show frequency response and I can tell them exactly where they are getting the heap of their SPL from. A weighting has a response curve that recognizes the average human ear at lower SPL levels and will negate lower and higher octaves. This reading will almost always be lower in SPL than C weighting. After 100db the human ear hears things relatively flat and compensation is not required, so the weighting used in the C curve is pretty flat and includes the lower and upper octaves. Fast vs slow is more or less peak vs RMS. The fast level reading shows more instantaneous peak levels, while the slow reading takes a reading every 1000ms / 1sec. and the meter moves accordingly giving a more average SPL level.
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To the OP - does your city have any ordinance or restrictions around festival/event SPL limits? In our city, they do and it's limited to 95dB at the edge of the venue grounds/area.
I realize that's a sketchy and potentially unenforceable policy, but you may want to check with the city to see what they have on the books.
They do have some noise ordinance policies, however as far as I can tell it was last updated around 1967. Even though we have residential here in downtown Kansas City, it's all zoned as commercial. That states that a reading of 80dbA is the limit at the "property line". We've never had the police called or respond to a complaint, I don't realistically think we will.
It seems like 105dbC would make sense. My line of thinking tells me this could cause the meter to spike if it's a kick heavy mix correct? It seems to me, that most people complaints about the volume aren't usually volume related and more about how the human ear perceives sound. Everyone can agree that 1Khz at 105db is painful, but 67Hz at 105db isn't really painful so to speak. Not sure if I'm making any sense here!
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It seems to me, that most people complaints about the volume aren't usually volume related and more about how the human ear perceives sound. Everyone can agree that 1Khz at 105db is painful, but 67Hz at 105db isn't really painful so to speak. Not sure if I'm making any sense here!
If you look at a the equal loudness curves, you will see that it takes a large change in dB at the lower freq to be perceived as the same as loudness change in dB at the higher freq.
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If you look at a the equal loudness curves, you will see that it takes a large change in dB at the lower freq to be perceived as the same as loudness change in dB at the higher freq.
I think you've got that backwards.
(https://www.sfu.ca/sonic-studio/handbook/Graphics/Equal_Loudness.gif)
At low to medium levels (<90dB), a couple of dB increase at 30Hz gives a curve that's 10dB apart at 1kHz.
ie, to sound twice as loud at LF, you only need a few dB. Through the midrange, you need +10dB.
When you start getting loud (>100dB), it looks like you need +10dB at any frequency to sound twice as loud. Interesting nonlinearity.
I believe all of these measurements are taken with headphones, however, so might not account for the tactile feel of loud LF tones.
Chris
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I think you've got that backwards.
Yeah-it's been a long day.
I know what I meant to say-but it came out wrong.
Thanks for correcting me.
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My experience has been that if someone doesn't want to hear the event, it does not matter how loud ( or quiet ) it is, it will still be too loud.
To the degree that I was doing sound at a venue and the venue management said I was too loud and breaking the rules. I agreed it was pretty loud, but what are the rules? They said 65db A at the property line. I asked them if the fence that the stage was 5' away from was that property line and they replied with a yes!!!!! I quickly informed them that it was an impossibility to meetthat demand and that so much as carrying even a conversation at the fence would break the rules. They said yes we understand, but that was teh agreement made by us and the property owner down the way. I couldn't help but tell them that they made a bad decision agreeing to that, as they would always loose.
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My experience has been that if someone doesn't want to hear the event, it does not matter how loud ( or quiet ) it is, it will still be too loud.
I know of cases in which the "noise" from the event is at or below the ambient noise. But you can still hear it. And people complain.
It is not the SPL they are complaining about-it is the actual music style.
No numbers or laws or guidelines will ever fix that.
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I know of cases in which the "noise" from the event is at or below the ambient noise. But you can still hear it. And people complain.
I worked in environmental noise here in the UK for a few years.... This is a typical problem and is why the standard of what constitutes a "noise nuisance" is usually defined by the environmental health officer's 'professional opinion' rather than a set level.
Where an event (e.g. festival etc.) is licenced, there will be defined limits, but these are set at the event boundary or at the nearest noise sensitive property.
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I did a property line sound study for an 'mall' where I was doing outdoor shows.
The town had called for some low number for the permit.
I had a level of around 80-95 dBA in the courtyard, and I found that the music was substantially quieter than the ambient noise at the property line, but you could still hear it.
The average noise level at the property line pretty much exceeded their requirement .
Buses, cars, wind noise and even the freeway over the hill were over their limit.
I have no idea what ended up happening.
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Yeah-it's been a long day.
I know what I meant to say-but it came out wrong.
Thanks for correcting me.
No worries, we all have them.
I found it quite interesting that the apparent LF SPL was so nonlinear with volume changes (ie, +3dB at 30Hz sounds like +10dB at 1kHz in some places, but crank it up and you need +10dB at LF to sound like +10dB at 1kHz) - hadn't realised that before.
Chris
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I know this probably will not help as most situations with residential are never easily solved as the complainant will simply continue to complain to local authorities until they get a better outcome than they originally hoped...ie. shut down.
However, I think that until there is some sort of agreement on the type of measurements that we use, we are never going to see much real compromise or even assistance from local authorities. We need to be educating all parties in the benefit of using Leq as the measurement standard. in either "A" or "C" or both. The real issue is the SPL over time as I think we all agree that louder for shorter is fine of quieter for longer. We need to display that we have acknowledge our duty of care to the patron and present a more accurate presentation of the data. Leq or LAeq is probably better.
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Leq is the way to go..... here's the sort of thing we would have to work to (attached)...
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I know of cases in which the "noise" from the event is at or below the ambient noise. But you can still hear it. And people complain.
It is not the SPL they are complaining about-it is the actual music style.
No numbers or laws or guidelines will ever fix that.
You can check in over at the Church Sound Forum if you want to hear this discussed At Length. :)
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d&b makes a program called NoiszCalc. It's scary how accurate it is. This will tell you what SPL is across the area. Take a look at that, then look at your local noise ordinances, and go from there.
I'd like to get some opinions on standard FOH DB restrictions. I'm going from a smaller Meyer PA where I didn't really need to enforce a DB/SPL limit to a new D&B rig that can easily outperform the Meyer rig. I'm in a downtown outdoor environment and we have brand new high-end residential towers just outside of the venue.
I see a ton of artist riders, but not many venue tech packs as I've been off the road and at this same venue for 4 years now. It seems like I use to see 105Dba at FOH on the regular.
What does everyone recommend? 105, 100 ??? A,C weighted?