Projecting Sound – From the rehearsal room to the concert hall

Part of the job of being a musician is to travel the world performing in different cities and festivals, which also means to play in different concert venues and halls. 

Of course, we all experience this in our every-day life: You rehearse for a concert in a rehearsal space, often well known (at least for established chamber music groups or orchestras) and then you meet the day of the concert for the dress rehearsal on the stage, usually unknown and experience, that everything sounds completely differently. You hear new things, that didn´t catch your attention before, some instruments become less audible. Sometimes you hear yourself much better, sometimes your sound gets completely drowned by the space; it is a completely new sonic experience. And that is challenging!

Acoustics influences your sound projection deeply

 On top of that, usually the time you spend in the performance space is limited, making it difficult to really understand the complex acoustic effects going on. You are therefore challenged to be flexible and, with experience, learn to adapt faster to the various conditions. 

However, is there something that you can do in advance, to be prepared for a new acoustics? And how can we prepare ourselves for this challenge? 

Well, to answer these questions we need to dive a bit into some aspects of acoustics. Of course, musicians are no physicists or sound engineers. However, some rudimental knowledge in space acoustics can be really helpful in our daily practice. 

In general, concert halls are designed and constructed to make sound beautiful, of course. 

One of the ideal scenarios, that every great concert hall in its own way achieves is, that even a not very pleasant sound reaches the audience and is perceived as something very beautiful. 

The experience for musicians on stage and for the audience in the hall is usually completely different. 

Let’s take some examples: you are all familiar with the perks of playing outdoors. Because of the total absence of any reflecting surface, the sound gets completely absorbed by the environment and disperses in the air. Bathrooms, on the other hand, usually have a very strong reverberation, because of the glass and ceramic walls, which bounce the sound back and forth, multiplying the sound source. The reason for this strong reverberating effect is that the walls are completely flat and are completely parallel to each other. In that way the sound creates standing waves. However, superacoustical spaces are not ideal to listen to music, exactly because of the loudness and the blurry reverb. 

Concert halls, on the other hand, try to control the sound reflections in order to avoid standing waves.

Professor Trevor Cox, who teaches Acoustic Engineering at the University of Salford, writes: “The sound bounces and reverberates around the room and so reaches the listeners from lots of different directions and spread out in time…This reverberation enriches the sound the orchestra makes, and with the right design makes you feel enveloped by the sound and involved in the music making.”

So, a good concert hall tries to “break” the main sound source and make it bounce in a diffuse manner, so, that the audience has the feeling of being surrounded by sound. This can be done in many different ways. Often concert halls feature curved or textured walls or sealing panels, which reflect and break the sound in the desired manner. 

Also, materials play a key role in acoustics. Metal and highly vibration-sensible surfaces are avoided in favor of wood and stone. F.e. during the last major renovation of the famous Teatro La Scala in Milan in 2002 (the theater underwent many major renovations; after a major disruptive fire in the 18^th century and later following bombing during World War II), the carpet was replaced by a terracotta pavement, which drastically improved the sound quality. 

Finally, the shape of the hall gives the most characteristic mark to its acoustics. 

For example, there are “shoe box-shaped concert halls (like the famous Musikverein in Vienna) or vineyard terrace-shaped halls (like the Berliner Philarmonie or the more recently build Elbphilarmonie in Hamburg), which proved to have outstanding acoustics.

Great concert halls also take care of reducing any disturbing vibration so that the audience can concentrate fully on the music. This often means to cancel low frequencies of trains and trams, which are usually very tricky. The Bridgewater Hall in Manchester solved this problem by suspending the entire structure using giant springs, which isolate the hall acoustically. 

Bridgewater Hall in Manchester is constructed with the support of giant springs that reduce the vibrations of trains and trams, ensuring a pleasant and uncompromised sound experience.

Now, we just found out how different aspects can influence the acoustics of a space, but we did not yet address HOW to cope with the particular acoustics of a space and how to adapt the playing to it. So, let’s focus now on the perception of sound, seen from our point of view…

As we discussed before, the acoustic feedback that we receive by the sound reflections of the space contributes largely to our own perception of sound while playing. It is crucial to get acoustic feedback, in order to control our playing.

An anechoic chamber, which gives absolutely no reflection back is the worst space to play, as we can barely hear our own sound. It is a terrible experience! 

On the contrary there are spaces which are superacoustical: they might increase the sound too much, raising the loudness to an unpleasant level. 

Often the flute is the instrument which suffers most from superacoustical spaces: it really becomes unbearable. The reason behind that is because of our volume sensation: The human ear is shaped in a way that it perceives volume in relation to frequency: this means that, with equal absolute volume, we perceive sounds with different frequencies louder or softer. 

And nature shaped us so, that the frequencies between 1 and 5kHz (exactly the frequency range of the cry of babies!) are the one to which we are most sensible. And the flute spectrum is mostly in this frequency range, too.

Somewhere in the middle between these two extremes, is our daily experience with the acoustics of concert halls. So, let´s now go back to the topic: How can we cope with different acoustics? Well, there are some strategies that you can adopt, to don´t feel lost or overwhelmed by a completely new acoustic experience. Some advice that can help you to react fast and give your best in any new space. 

There are some aspects related to learning to compare spaces,  by having a known reference, that can help to adapt more quickly. So the rehearsal space plays an important role. 

When playing in large concert halls, the precise source position and point of perception become also crucial for the sonic experience. Learning to develop an ear for the perception of projection has enormous impacts on the ability to perform with ease in every concert hall. 

So there are a lot of aspects that can be integrated easily into each flutist’s workflow and can improve the awareness and train your ears to listen more carefully. 

At this point, let me add a final advice, slightly off-topic: if you are looking to buy a new professional instrument (I will cover this topic in a separate article, so stay tuned for that!), I highly advise you to don´t miss the chance to try out your favorite choice on a stage. Ask your teacher, mentor or colleague to go with you. It makes a huge difference how you perceive your instrument and how the sound is perceived some 10 or 15m away.

About the Author:

Alessandro Baticci is a flautist, composer and inventor from Italy. His international music activity and his focus on contemporary techniques has shaped him to be a versatile player, navigating from classical to modern music effortlessly. Alessandro is also active internationally as a tutor and teacher in various masterclasses throughout the world. His compositional experience has also shaped his vision of sound production, interpretation and aesthetics.