I realise this thread shouldn't really be in here but I thought it most likely I'd get decent feedback in these here parts.

Basically I'm doing a report on acoustic design in stadiums and was wondering if anybody knew any good scientific studies into how to design a decent acoustic environment. I'm thinking something on the new Wembley would be decent, what with one of it's PR lines early on being it was specifically designed to create great atmosphere.

I'm probably going to be comparing the City Of Manchester stadium to Old Trafford too, talking about how roofline incliments can help trap fan atmosphere, so anything in terms of schematics for either stadia would be awesome (like those Allianz/Wembley/La Luz comparisons that were doing the rounds a year or so ago).

Cheers guys.

It's not the kind of feedback you were probably expecting, but if you're writing a report on acoustic design in stadia, it ought to be called "Stadium Acoustics", and when comparing COMS and Old Trafford, you're discussing the schematics for either stadium.

HTH :D

Many people have this problem with Fathers and Mothers in Law.

The best acoustics of any stadium will be in the new Wembley.

Well, no offence but those two replies are the most pointless in the history of human existence.

This place used to have shit loads of info and drawings (cross sections and such) from all new stadia developments but I cannae find the buggers now. Somebody must be able to a help with those at least?

And surely on SSC there are some engineers who know about this gumf? Nobody here knows anything about acoustic design despite long similar topics from a couple of years ago?

If not, then let's get a discussion going. What elements of new stadiums are acoustically designed? What is it that makes a stadium's atmosphere better than elsewhere? As previously posted, I'm going to look at COMS and Old Trafford and hopefully offer recommendations to help reduce the sound loss at COMS. Obvious factors between the two are OT's sloping roof, which helps reflect the sound towards the fans and pitch, but also helps create standing wave issues towards the back of the stands (North in particular), thus giving fans in this stand a greater sense of atmosphere. COMS with it's "open" roof, sloping to the sky, allows the sound to simply get lost and leave the stadium, only allowing a small percentage of fan noise to actually hit the pitch etc.

So as a small idea, I'm thinking some kind of hanging hard material acting like a curtain around the edges of the roof, so that any sound heading upwards will hit them and reflect back to the roof, then back towards the stands.

I've probably worded the above really badly, but you should get the general idea of what I'm on about.

So then, who can help me?

This sounds like a fascinating project and I would look forward to reading your results.

I'm not and engineer, but I have a number of issues to raise.

Firstly you need to be more clear about the distinction between 'atmosphere' (a subjective and therefore immeasurable quality) and 'sound loss' (an objectively defined vector quantity). Otherwise you will get crackpots trying to argue the case for their own particular stadium with no recognition of the facts. For example, the most atmospheric stadium I have visited is the home of Aldershot FC, but it certainly wasn't the loudest - that would be Murrayfield in 1990 when Scotland won the Grand Slam (interestingly, this stadium was still largely terraced at the time and the place where I was standing had no roof...)

Secondly, you will need to consider ways to isolate your variable of interest. i would have thought that many factors other than roof angle influence sound loss: prevailing wind, precipitation, distance of spectators from pitch, separation of stands, roofing material, number of tiers, capacity of stadium, density of spectators within stadium, general temperament of fans, time of day (i.e how much bevvy has been consumed by the spectators), the relationship between sound produced and sound lost - is it linear, exponential or log-linear?

Thirdly, sound inside a stadium is not constant - it comes and goes according to the circumstances on the field of play. Are you talking about general noise in regular play or after a goal? What about the pitch of the sound - is OT better at holding on to key 'atmosphere generating' frequencies than CoM?

Fourthly, I would have thought that if the sound loss issue (if indeed there is one) at CoM could have been solved by hanging a curtain from the rim of the roof then the original architect would have done so. I suspect the solution would be far more complicated than this.

Despite these things, it does seem clear that OT is quantitavely as well as qualititatively different from the City of Manchester Stadium and I think this is a valuable project. However, I'm sure you could search a database of technical journals to see what is already known on the subject. All the best.

Nice one. Sorry about the eloquence of my posting, My mind has been ravaged through the years and now resembles nowt but a small, mouldy pea.

Firstly I'm thinking about looking into bowl shapes. It's common knowledge that new stadiums tend to be built with a far larger footprint than what we've all been used to (Wembley itself is a perfect example). Without going into specifics, it's fairly sound to say that the bigger the bowl, the further distance sound has to travel, so with these big open bowls we currently see developed, there's more "space" for sound to get "lost".

My example of COMS comes from a few things. I'm a City fan and have noticed the massive difference in fan noise from the days of Maine Road. Maine Road was lovely and compact with low roofs (except the new Kippax) and decent gradients on the seating levels. The open corners of the Kippax allowed wind in quite a bit, so this would've been a factor in helping sound travel throughout the stadium too. However my experience of COMS is a bit hit and miss. There are a lot more plastic fans about so that obviously is a factor, but from a subjective point it does appear a much quieter stadium than Maine Road.

I'm thinking this could be down to a few things. As already stated, the angle of the roof doesn't appear to help. Bearing in mind the stadium was designed primarily as an athletics ground, the roof in reality is fine. As you can see from the very last image here...

http://www.arup.com/DOWNLOADBANK/download71.pdf

...when in athletics mode, the roofline matches the bottom tiers nicely (providing 100% rain cover) and the goal end doesn't have that much distance between the roof tip and pitch level, therefore less distance for sound to travel and closer to reflective surfaces. But since the 3rd tiers were installed, this has increased not just the size of the seating bowl, but also the height of the roof's tallest point to the pitch level. This should mean that those on the bottom tiers pretty much have nothing to reflect sound off of.

The gradient of the tiers is also something I'm interested in. The new bottom tier of COMS is rather flat, especially behind the South Stand goal. So in effect, people are more or less infront of each other, instead of "on top of each other", as you would find at say the Bernabau. With the steep incline of a stand, it'll increase the pathways of waveforms aimed towards the pitch with little absorption, but if you're in quite a flat area like some parts of COMS, your noise will simply be hitting the gent in front of you and limping towards the pitch, instead of nose diving to the pitch like at the Bernabau.

Ashburton Grove interests me. The sloping roof is there due to planning restrictions as well as pitch airflow, but does anybody know if stadium acoustics also came into thought when it was designed?

Good point about the distance between pitch and the stands, I'd completely forgotten about that. This may be a factor at COMS, firstly because we have the largest pitch in Britain and secondly there's also a shitload of extra space between the grass area and the stands. This could effect the general perception of saound also.

As for the "sound not being a constant" thing, aye, I'd considered that and was simply looking at this report in terms of enhancing peak level noise. As I said, COMS appears quieter to Maine Road, despite the ground offering 14,000 extra seats.

The curtain thing I'm talking about was rather simply put. I'm thinking something similar to those fire trap canvases that you see hanging from the ceilings of new shopping centres, but possibly with a harder material (thin sheets of rubber or something). Basically so that those sat at the rear of the upper tiers will actually have their noise being reflected back towards the stands instead of simply "gliding" up the roof and not coming back. Obviously I need to put a bit more thought into this.

Thanks for your post though, you've given me some things to think about there. As for looking through journals, I'm a ponce with things like that and don't even know where to start to look. I'm only a wee student trying to get a mickey mouse degree so this isn't some professional scientific study into stadium acoustics, although who knows where this may eventually go when it's handed in.

The Parc Des Princes in Paris must have a good acoustic shape because thats the noisiest stadium I've been in so far. Half full it's pretty loud but full it can be deafening.

. As for looking through journals, I'm a ponce with things like that and don't even know where to start to look. I'm only a wee student trying to get a mickey mouse degree so this isn't some professional scientific study into stadium acoustics, although who knows where this may eventually go when it's handed in.

Well played dgnr8: it sounds like you have a good rationale for your study and have considered the issues carefully.

I wonder if I may be so bold as to repeat one or two bits of advice.

Firstly, don't dismiss out of hand the 'professional' journals. Your college library will be able to show you how to search through an online database - it's surprisingly easy and if somebody has already done similar work then you can borrow their structure and language.

Secondly, and probably more importantly, I think you need to stick to one variable, otherwise you will end up with a PhD sized project. Of all the things you've mentioned, I would think that the angle of the tiers behind the goals will be most amenable to investigation - but if your feel more strongly about the 'roof curtain' then go for it but don't muddy the waters by looking at something else within the same project. I'm a researcher myself and its something I've learned the hard way that when one is excited about a particular subject then one wants to do everything immediately. I've found that limiting myself to one particular research question helps me to make projects manageable and to give clear succinct results.

I hope this helps.

The best acoustics of any stadium will be in the new Wembley.

How was that comment pointless!!??

I was in Parc des Princes when PSG beat Rosenborg 7-2 in the Champions league a few years back - very loud! The fans on the Metro were not so loud however, more like morning commuters on the London Underground.

The best acoustics of any stadium will be in the new Wembley.

their 5000 speakers should put my cruddy 7.1 set up to shame:nuts:

allianz would be up there...etfe exterior keeps the noise in.

Yeah whenever I see a Bayern Munich game on the tele, its always loud, and listening to it on the tele is never a good judge of the stadium acoustics, so that would indicate that it is MUCH louder in real life.

I hear Wembley's will be tremendous. Whilst its a big stadium, the bowl is a peculiar shape and it will help to trap the sound, whilst the fact that 90,000 fans are so close to the pitch will be amazing. Its a big stadium, but the playing area does look compact.