In my September 2009 article Certifying Outdoor Live Music Venues, I suggested that, rather than creating an acoustics training and certification program for sound engineers as the Live Music Task Force suggested, it would make more sense to certify the venues themselves. The subject has come up in recent conversations so I went ahead and fleshed out the idea to a fully developed system for analyzing and certifying venues. The slideshow presentation below explains my proposal for a system where issuance of outdoor music venue permits are contingent on a noise impact analysis being performed on the venue.
The impact analysis considers potential impacts to nearby residences and, based on a relatively simple and repeatable analysis method, determines sound level limits specific to that venue. The sound level limits for each venue will be specified in multiple locations, including at the mixer, and will be back-calculated from the maximum allowable residential noise impact. The presentation goes far more detail and discusses my reasoning for the idea. It might be a bit of a thick read, but there is a step-by-step example with pictures that starts on slide 15.
What I want people to take away from this, more than anything, is the idea that basing the conditions of a music venues permit on its actual residential noise impact implicitly encourages owners to locate and build music venues with noise as an initial consideration. Currently in Austin there are too few venue owners who are concerned about the noise impacts they create and are willing to take steps to be better neighbors. Under the current system there is little incentive to operate this way outside of accumulating karma and receiving fewer angry phone calls. Under the system I am proposing, venues that are located, built, and organized in ways that reduce noise impacts will reap tangible benefits in the form of higher sound level limits at the mixer. Being a better neighbor is automatically incentivized.
When reading through the presentation, don’t put any weight on the specific sound levels that are used as examples. They’re just examples. The important idea is using a procedure that is objective, fair, and repeatable from venue to venue. When a procedure like this is implemented by the City, the specific sound level criteria can be later decided based on a careful study.
Why should existing venues be punished for people willingly building and living right next door?? How do you propose that existing venues, which can barely afford to keep their doors open anymore, go ahead and purchase these pre-determined plots of land? Do you know how expensive real estate is here? Have you personally ever done sound at a mid to large scale venue? Your straight line sound surveys are going to take a year or more as the propagation of sound waves varies dramatically with temperature and humidity, and guess what??? We have MASSIVE variations in both here in Austin. This does not even address the issue of sound wave refraction, and omni-directional bass wave propagation, which CANNOT be measured accurately with straight-line dB surveys. The lack of scientific reality in this debate is frustrating. The current city council has shown much greater interest in tax abatement’s for wealthy employers, and checks for their re-election committees, than any attempt to actually understand the issues at hand. That would require an INQUIRING mindset, sympathy to the residents of Austin that are not wealthy, and the desire to come to a real compromise. We all that is not going to happen. SO, by all means City of Austin, keep it up. You are destroying what made this town great, and replacing it with corporatized, cookie-cutter blandness. I cannot tell you how many of the artists that I have worked with in the past have re-located to friendlier towns, firstly due to the massive increases in cost of living here coupled with no net wage gain( most musicians don’t work for Dell), and then the COA’s developer inspired and financed jihad against live music wherever they feel like building their next eyesore.
Sincerely, disgusted former and sometime live sound engineer,
Aaron Shannon
Hi Aaron,
Thanks for visiting the site! You ask some very good questions and I’ll do my best to answer them for you. I intentionally did not go deeply into the technical aspects in the presentation because the intended audience doesn’t care about that level of detail. I am happy to discuss the nitty gritty with anyone who’s interested, though.
The issue of an existing venue with a new residence built nearby is easily solved with a grandfather clause. Also, consider the opposite situation; why should an existing residence be expected to tolerate a group of new bars put in where there were none before (eg W 6th St)?
I have personally participated in the design of mid to large scale venues, and in the design of sound mitigation for existing mid to large scale venues. As an acoustical engineer, I am not the person who mics the band and mixes the show (though people often make that assumption). My work is usually finished before the first band takes the stage.
Sound propagation does indeed vary with temperature and humidity, but not as drastically as you seem to believe. Considering the short distances between local venues and their neighbors, the effects are just about negligible, especially at low frequencies, which cause the most concern in this situation.
Let’s take at an extreme example: 32 degrees and 10% humidity vs 100 degrees and 90% humidity. The expected difference in attenuation per 1000 feet (a much longer distance than will come up in this situation) is 0.1 dB at 63 Hz, 0.3 dB at 125 Hz, 0.7 dB at 250 Hz, 1.3 dB at 500 Hz, 1.2 dB at 1 kHz, 0.2 dB at 2 kHz, -2.7 dB at 4 kHz, and -6.6 dB at 8 kHz. At 250 feet, that amounts to a difference of about 1.5 dBA.
Also, there’s no reason that the acoustical engineer doing the venue analysis couldn’t take temperature and humidity into account; the effects of temperature and humidity on sound propagation is well documented. It’d be a simple matter to record the temperature and humidity at the time of measurement, check the distance between the source and the receiver location, and scale limit levels appropriately based on the worst case scenario. The same could be done with wind. You may not realize this, but environmental sound level meters usually have inputs for weather probes so that temperature, humidity, wind speed, and wind direction can be automatically saved alongside a measurement.
Refraction and frequency-dependent propagation patterns are inherently accounted for using the measurement method I’ve proposed. There’s no “straight line” about it, it’s measurements at specific locations, subject to the same acoustic effects that always exist. Sound behaves the same whether or not someone is measuring it. As long as the venue doesn’t change, the relationship between sound levels at each point won’t change.
I agree with you that the almost complete lack of good acoustics in this debate is very frustrating. I am doing my best to change that. I have been fortunate enough to be invited to participate in a working group that is addressing this very topic. I have discovered that the people involved in the discussion typically are open to considering good acoustics, they just haven’t been made aware of it. Meaningful, scientifically-based change may be coming soon; stay tuned.
Something you should keep in mind, being pro-venue as you are: the current noise ordinance is extremely anti-venue. 85 dBA at the property line is all but impossible to satisfy for any of the small venues along 6th street. Take a SLM out on a Saturday night, go from venue to venue, and you’ll see what I mean. APD could write a ticket to just about any venue at any time (provided there’s a complainant). There’s a reason the vast majority of other cities have a receiver-based ordinance (as opposed to our source based ordinance), it’s the only way that’s fair to everyone.
-Josh
Also, your sat imagery is great, but what about topographical reality? Austin is far from flat. There are large variations in elevation in many venues which are going to cause refraction of sound to unexpected places. Are we going to do 3-dimensional modeling for every venue that wishes to be issued a music “permit”? That sounds real expensive to me. And that is the only way to realistically and fairly implement the plan you have. I am not trying to beat you up on this, only trying to point out some the issues that seem to be getting glossed over. You seem to be more sympathetic than most. What about highway noise from I-35?. Does this mean that U.T. football games will need a permit? Because I can hear them at 45th and Duval if the wind is right. All questions worthy of consideration…
AS
Hi again Aaron,
All questions ARE worthy of consideration and I’m happy that you’re asking them.
At the distances that would be involved in analyzing OMVs, changes in topography will be small. But it doesn’t matter, because just like with refraction and frequency-dependent propagation, all physical effects are automatically accounted for when taking measurements at specific locations.
When it comes to modeling, yes, computer models are 3-dimensional. Accurate topographical data is free and easy to acquire in a variety of formats. Any of the modeling programs I mentioned in the presentation work in 3 dimensions.
Time spent creating a computer model can be expensive, yes. Remember, though, that modeling isn’t required if the venue already exists, which will almost always be the case. Only brand-new venues that haven’t been built yet will need it, because measurements won’t be possible. In fact, it may not ever be necessary to build a computer model.
Highway noise from I-35 certainly does raise broadband ambient levels. Any semi-competent acoustical engineer would know to take that into account in the situation that traffic noise exceeded venue noise at a receiver. It’s simple enough to take ambient measurements before taking measurements of generated noise from the venue and compare them.
Is Texas Memorial considered a live music venue? If so, they already have a permit. My presentation doesn’t ask for more permits, it only explains a way of issuing permits that encourages venues to be good neighbors.
Thanks for responding Josh!! My next question then is how will venues afford the sound-metering equipment that you mentioned? I have not personally used the equipment you mentioned, but when I was actively working as a sound engineer, the permit issue was a non-factor. Next then, if we can surmount the cost issue, we are going to have to have training for SE’s. I have come across sound “engineers” that are lucky if they can tie their own shoes, much less parse and understand the post you just made, or take measurements and solve a simple few equations. Also, most engineers are lucky if they make 100$ a night, 2 or 3 nights a week. One reason I am a former live-sound engineer. It’s just not very lucrative unless you are one of the lucky few that goes on tour(is that lucky?) or has a permanent gig at a money venue. I completely agree about the current sound ordinance. I have measured 70-75dB at the door of Cedar Street from ambient club noise( also known as drunks hollering), so I do know and agree with you about the small-venues compliance issues. When I was at Cedar Street, they had just implemented the SPL ordinance, but had yet to permit anyone. The police would stop by and measure from the property line, but we never had any problems from them. My gut feeling is that they thought it was a waste of time, and weren’t about to spend an hour doing paper work on a SPL violation on Saturday night downtown Austin/// Anyways, thanks again for answering my probably too-emotional letters, and I’m glad to see you ARE taking all this into consideration so that we will still have a music scene here..
Thanks,
Aaron S
The analysis that is done for the permit would be done one-time by an acoustical engineer, presumably working for the Music Office. Remember that there’s a significant difference between an acoustical engineer and a “sound engineer.” An acoustical engineer will be someone with an engineering degree and, hopefully, a PE license from the State. So, presumably, they’ll be able to tie their shoes.
The Music Office already weighs in on whether a venue gets a permit, though I have no idea what their current procedure is (anyone who knows, please e-mail me or comment!). The type of meter required to do the assessment properly will cost somewhere in the $3k to $7k range; expensive for a small venue, but not that expensive in the scope of every venue in town. A venue will just need a simple SPL meter at the mixer if they want to check their compliance; even a Radio Shack $50 special will be sufficient for that purpose.
From my limited interaction with APD, I have gathered that they do sometimes consider investigating noise violations a low priority. My proposed system is meant to make their lives easier by doing the bulk of the enforcement work on the front end; the resulting sticker on the door tells them exactly where to stand and what to measure. All of the officers I’ve talked to about this are pretty sharp, I don’t doubt that it’s well within their understanding.
Well, Josh, I have to give you credit. This is starting to sound a lot like a business proposal for yourself and/or services to the City of Austin. Good luck. Ultimately, the less enfranchised are going to have to pay for this when they can least afford it. I am going to maintain a healthy level of skepticism in the dealings of the City of Austin and the music community at large.
I understand your skepticism. But, as far as I know, the City already has the talent inside the Music Office. Outside consultants shouldn’t be needed, and a new hire to the City shouldn’t be needed.
OK, fair enough. So what’s your angle in all of this? Do you live downtown, are you working for somebody? Seems like a lot of trouble to go to for purely altruistic reasons.
That’s an honest question that deserves an honest answer. This website is my hobby. It allows me to write about acoustics in a way I don’t typically get to. During the day I do analysis and reporting for clients who can afford the services of an acoustical engineer (architects, developers, etc), which is interesting and rewarding, but rarely gives me the opportunity to get into community noise.
Through this website I’ve met a lot of very interesting and cool Austin people, which is the best part of all of this. I would truly consider some of the people I’ve met friends. Occasionally I even pick up a small paying side job, which is icing on the cake.
One of the things I love most about Austin is that the people who live here have a real sense of ownership of this city. There are a lot of Austinites who put a lot of work into improving this city with no expectation of compensation beyond recognition of a job well done. Compared to the work I’ve seen others do, this little website is a pretty small effort.
The presentation that I posted was inspired by recent discussions I’ve had with people in the downtown community (who contacted me through this website) on concepts for an improved noise ordinance. It was the best way I could think of to explain my ideas. I’m not the only person with venue-specific permitting in mind, I just happened to have a very specific notion of how to do it. Since I went through the trouble of creating a 22-slide presentation, I figured I might as well post it here.
Hopefully that answers your question.
I can respect that.