Finding the perfect soundproof door for concert halls
In this series of articles we’re covering the special requirements of particular environments to see exactly what’s required in the way of acoustic or soundproof doors. Last time we looked at sound or recording studios, which due to the nature of what they are designed to do have very demanding acoustic specifications.
In this article we’re taking a look at the needs of concert halls.
What are the characteristics of a concert hall?
For a start, unlike a recording studio, they tend to be large – with seating or standing room for hundreds and possibly thousands of people. Another significant difference is that the venue’s acoustic requirements will have a different emphasis – it’s not so critical for sound to be contained within the auditorium, but it is important that (as far as possible) sound doesn’t escape from and into the auditorium.
Then we have to consider the overall acoustics within the venue itself, and how to ensure that the performance sounds as good as it possibly can to everyone in the audience.
And when we think about the number of people constantly moving around, and the need for the doors to perform the required level of soundproofing as well as fulfilling safety requirements (e.g. fire protection), we see that it’s a real challenge.
If you’re interested in how to solve it – read on!
Designing a concert hall
- Unsurprisingly, the process begins with testing, using an acoustic model. There are two types – scale models and computer models. The level of detail required for an acoustic model is greater than that for an architectural model – for example the materials must be the same so that the tests accurately reflect what will happen to sound in the finished hall. As the model is smaller than the real hall, the frequency of the test sounds must be proportionately higher (e.g. in a 1:10 scale model the sound frequency must be 10 times higher than it would be in the real hall). There’s clearly a lot to it!
- The shape of the hall is critically important. Do we opt for the “shoe box” shape (long, tall, and narrow), which has beneficial side reflections, (such as the Royal Festival Hall)? Or the fan-shaped hall, with reduced side reflections, like the Barbican? Or perhaps the “Vineyard Terrace”, where the audience is subdivided thus providing more beneficial reflections from the dividing walls (a good example is the Berlin Philharmonie)?
- And what about the walls? Do we want them to reflect sound back into the auditorium, to absorb the sound, or to disperse it in different directions?
- Studies have shown that the volume of the sound reaching the listener is the single most important factor in determining their emotional response. One of the pre-eminent concert hall designers and acoustic engineers of the twentieth century, Leo Beranek, wrote: “The thrill of hearing Bach’s B minor Mass, Beethoven’s Ninth Symphony, or Mahler’s Eighth Symphony is not only determined by the quality of the orchestra and interpretation of the conductor, but is enhanced immeasurably by the dynamic response of the concert hall. Response means both quiet support for the pianissimo parts and majestic levels at the fortissimos”
- Earlier we mentioned the importance of ensuring that unwanted sound doesn’t enter the auditorium. Many concert halls are in busy city centres, with lots of traffic noise within a very short distance. Excellent sound insulation is therefore needed.
We told you it was a challenge!
Make sure you use the experts
Just as with recording studios, you’ve read how complex the overall design process can be. And within the hall, having soundproof doors will as always play an important role in the overall acoustics.
Once again, you’ll need expert advice and guidance to get it right. Visit our home page or here to go straight to our contact page, where you’ll be straight in touch with people with a successful track record.
