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.

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.

Thanks,

Aaron S

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 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

AS