Decreasing sound output of a marquee

[mac.calder]

I have a marquee that has a few noise issues - it is put up at the venue I work at for the summer months as an additional function space (generally weddings, x-mas parties and the like). 3 or so years ago, a bunch of developers bought some land next to the venue I work at, built high-density apartments and sold them off for a pretty penny. Despite the fact that it was a well known fact my venue put up a Marquee every summer we are the big-bad-people according to the council.

 

So last year they implemented a few measures which reduced the complaints to next to none (there are 3 people who complain on principal every year because they can). The Acoustics Engineers reports stated "Noise at the perimeter of the apartments is hard to measure as it is quieter than the frogs in the surrounding creek". This year, due to a number of reasons, the Marquee has moved about 35m closer to the apartments and we are having no end of trouble. Obviously this is AV's fault, not the venues, because that is how things work, so we are trying to think up some solutions.

 

Currently we have a sound ceiling directly above the dance floor - it is quite directional, 100dB under the sound ceiling is just over 80dB at our ops desk 18m away. Apparently (and this makes no sense to me) even then, the levels at the apartments (about 35m away) is still too loud.

 

The Marquee is silk lined with standard vinyl on 3 sides and a glass wall on the other. My first instinct would normally be to hang some heavy black velvet drapes - but the marquee is 30m x 30m and apart from spoiling the look of the venue, I don't have 90m of drape to spare.

 

Any suggestions would be really appreciated. The noise wars occurring due to this marquee are getting ridiculous.

[kerry davies]

There is a planning provision in some parts of Europe and, I had thought, parts of Oz where retrogressive complaints were disregarded. That is, the noise was here before you, go away. Nobody ever bought a house next to Man U and expected peace and quiet!

 

Saying that, it obviously does not apply or is being flouted where you are. Assuming you have done what you can with design of system then a quick and relatively cheap solution is to get the marquee boys to remove the linings, hang blackout lining and re-hang the pretty linings over the blackout. The glass wall is problematic but keeping doors closed as much as possible makes a big difference.

 

Make sure there is as little physical contact between sound ceiling and framework as possible and take the best measurements you can at the perimeter, best to know exactly what the facts are when arguing the case. Try not to push volumes when the dance-floor is empty thus reflecting the sound ceiling. Obviously the music makes a difference and repetitive dance beats will be difficult to manage as the perception is greater. If all else fails they may have to re-site the marquee just to be seen to be a "caring" neighbour.

 

Finally one "neighbour" to a regular gig was so reliable the EHO had his office phone diverted to his mobile and sat outside her house on gig nights. We slammed the volume to 11, she called, he visited and phoned us from her lounge, we turned it down, he said "I have done what I can" and he went home. Perception!

[Jivemaster]

As you are in Australia UK law and precedent may not apply. I really suggest that you get legal counsel involved, your party was there first etc, but it's not a certain case. The chance of getting a marquee to contain 100dB is NIL you would need major walls to do that. In the UK there was recent case law that flats were built near an established squash court, the squash club was closed due to noise complaints.

[mac.calder]

It is a bit of a licensing issue - Because it is a temporary structure it needs to be approved each year and granted various licenses to operate. Local council is basically sitting there going "You pull your levels down and ensure we get no more noise complaints or we pull your license to serve alcohol" etc.

 

The sound ceiling is as isolated from the structure as it can be - it is hung from chain motors from the ceiling

 

http://i21.photobucket.com/albums/b273/maccalder/319241_10150327637809609_755894608_7570823_931708294_n.jpg

 

There is talk that building an "orchestra shell" of some description around the band might help (I think stage noise is minimal). Another is building an "insulating wall" of some description between us and them (I have no confidence in it doing anything unless it is about 20m high and 100m wide).

 

I was wondering if anyone knew of a solution like active noise cancellation - especially for the low end. I know it can be done with "predictable" noises like fans - just wondering if anyone had any experience of a system that can be fed a dynamic input

[csg]

one of the christmas marquee venues that I supply sound for, based in very central london has a lead quilt lined steel sound box structure which encloses the band stage and dance floor area, leaving the side opposite the band stage open. Obviously this is a big, heavy and expensive solution, but it does give us a reduction of approx. 15dBA measured 20m from the side of the venue compared with the structure not being used.

[Simon Lewis]

.... but it does give us a reduction of approx. 15dBA measured 20m from the side of the venue compared with the structure not being used.

 

 

There's the problem... big solid structures partially enclosing a noise source for only15dB noise reduction... about the same as lightweight internal door.

 

I would be looking for a number of solutions, including working with those raising the complaints (what exactly is their grievance, what are they hearing, what is the spectral distribution, duration, time of event etc. can they be persuaded to relocate for all or part of the event?); considering the noise source and checking if directivity can be used to ameliorate complaints (e.g. use of cardioid subs etc.),; use of barriers (e.g Eve Trackway) positioning of loudspeakers and so on.

 

The prior activity clause in English law works only if you were there as a business for 25 years (or this was the case last time I checked our arcane legal system). Not sure how Australia works, but it is not unusual here to see cases of townies moving to the coutryside, then formally complaining about the noise of cockerels.

 

 

I sympathise with your plight, but having been on both sides of the sound level meter I can only say that there are few easy solutions, and you will need to spend some money - and even then it may not satisfy your complainants.

 

 

 

Simon

[S&L]

In my day job (building services engineer) I have reasonable amount of experience designing and retrofitting acoustic solutions to air handling plant to satisfy UK EHO enforcement orders. One particular plant I had wouldn't work with direct connections to plant and so as a design team we designed acoustic screens - think of them like fencing screens but constructed from acoustic material. the principle being to absorb the the heavier end of the sound (those frequencies with high dB) before the noise escaped to the surrounding area and reflected off nearby buildings. screens aren't perfect since not all sound is aimed at the screens but killing as much of the noise as possible at source obviously means whatever remains reduces further as it travels distance and the net effect of modest reductions at source can have much more marked db drop off by the time the sound arrives at the complainant.

acoustic screens when purchased from manufacturers can be very expensive but it may be possible for you to design and construct panels yourselves for a more reasonable cost. I have never tried this applied to a venue or music as distinct from machinary but the same principles should apply - something to think about at any rate

[ramdram]

We have had a similar situation. The local residents surrounding our venue are quite decent folk and even stumped up a extra panel for our "tent", quite a few hundred £££. However, they makes it obvious we have not thanked them enough because one local "complains" by mowing his acres (yes) of lawn all evening 'til 10pm.

 

The answer was simple, free tickets for any show any night of the season. We don't have numbered seats as such and we very, very rarely have a completely full house. So a free set of tickets, at zero cost to us, results in peace and quiet, from him, and as the guy is not a tee totaler we see an increase in income over the bar. He brings his friends too (at his or their expense, we don't know, we don't care) and they help to swell the bar profits.

 

So, in view of the anecdote, have you considered simply buying off the local residents with free "passes"/season tickets? Once ( granted, if) they accept then it is a stick with which to defend yourself if ever things got "sticky".

 

Are you pandering to the objectors? Depends how you look at it. If you lost your liquor licence (?) how much would your income decrease by? How much have you invested in this sound deadening kit?

 

You mention you don't have the extra 90mtrs of drape to spare, tough, suggest you find the drape and do a public relations exercise with the residents and show them you are trying to resolve the issue. If ever you ended up in court I would hazard the legal fees would dwarf the expense of the extra drapes...which you might have to splash out for as a condition of restoring peace and harmony.

 

FWIW, some folk have moved into the "countryside" here in UK and have managed to get a gagging order on the local cockerel, even though they knew that living in the countryside could be noisy. The irony being they moved to the countryside to escape the urban noise.

[Junior8]

Have you checked whether, putting on your unbiased hat, the neighbours have any justifiable cause for complaint?

[Jivemaster]

In a situation as the OP describes the first complaint calls probably get made when the marquee lights go on! BUT the council has to be seen to act and can well close the whole venue down. The only real option is to build a big venue with massive walls and roof and significant effort put into noise nuisance avoidance, including the doors and carpark.

[RichM]

Cardiod subs?

[Simon Lewis]

There is talk that building an "orchestra shell" of some description around the band might help (I think stage noise is minimal). Another is building an "insulating wall" of some description between us and them (I have no confidence in it doing anything unless it is about 20m high and 100m wide).

 

To answer the specific question, noise cancellation can help, but you'd need a 2D array of microphones each feeding an error correction circuit and an independent playback channel, Not a very cost efective solution perhaps?

 

The problem here, is people are saying the right kind of things, but you need someone on the ground who can analyse, advise and intervene with a level of authority on the political, legal and social issues, and provide specific measurable and achievable acoustics advice. Over here, I'd be suggesting people like Vanguardia. The only Aussie acoustician I know is Glenn Leembruggen, but he's a long way away from you...

 

It is entirely possible to waste money trying to reduce noise from marquees. In addition to any directivity measures taken, you need isolation, and not just absorption. Furthermore, taut PVC has a wonderful ability to reradiate low frequencies so that at a distance the bass beat is heard clear as day with minimal mid-high frequencies. This can add considerably to the noise nuisance experienced.

 

If this event is to continue, I'd suggest it needs some professional help, not good intentioned tinkering ;-)

[mervaka]

what is the site like? is there room to build up an earth wall? :)

[mac.calder]

Ramdram - it is corporate, so unlike theatre, we cannot bribe them with tickets. The liquor license is a big thing... Imagine trying to tell a wedding party paying for a 5 star venue no champagne! Re: showing the residents we care, the venue has spent over $80k on measures to reduce SPL over the last 2 years. There would be no court case involved - because you cannot file a suit against a council for revoking a liquor license or license of capacity - they are handed out at the discretion of the local council. I think the complaints are largely because the residents made a bad choice moving next to a casino and the Marquee is a soft target.

 

Junior8 - I have stood outside the housing estate whilst an event is on, to me, it is not something I would complain about - that is very subjective though. The ambient noise level there changes from 68dB (no audio from the Marquee) to 73dB.

 

Rich - there are no subs in the venue at all... The only PA we use is the sound ceiling (which is 270 odd narrow throw drivers pointing at the floor) with 4 mackies flown along the edges - the mackies being used to amplify speeches etc, not for the bands.

 

Simon - the venue has engaged the services of an acoustic engineer for the last 2 years. He wants to take some time to observe this years configuration before making any recommendations. It's good that he does not want to rush in half-cocked, but then again, each day is another day where more complaints come in - (laughably, a couple of complaints have been about dark nights).

[timd]

(laughably, a couple of complaints have been about dark nights).

I would argue that the fact that such complaints have been made significantly decreases the strength of their arguments and suggests that they're complaining for complaint's sake.

 

Tim