The Lombard Effect

Harmonia takes a closer look at the ambience of restaurants

Don’t you hate having to shout above the noise in a restaurant? Or being unable to hear the conversation in a bar because it’s too noisy?

How often have you attended a large event where the conversation is a free for all? The general noise level often increases within the room and with it your own voice rises so that you can be heard over the next person. By the end of the event you are hoarse and your ears are ringing. Not pleasant!


There is a name for the psychoacoustic effect behind all this: the Lombard effect. First reported by Etienne Lombard in 1909, his namesake is still causing us problems a century later.

In a noisy environment, people speak more loudly. This makes the environment noisier, which in turn means they raise their voices. This can quickly cycle out of control to create the awful environments that we are so familiar with.

Since the problem particularly afflicts restaurants, we did a little survey (of 178 people) to see whether it was just us who were bothered by it. We obtained some interesting results…

  • 30% found their last dining experience too loud
  • 24% regularly have to raise their voices to be heard
  • 44% will choose a restaurant based on whether it is noisy or not
  • 81% will not stay as long in a noisy restaurant
  • 5% of responders suggested that they are more likely to use a takeaway than eat-in as the noise in restaurants has become uncomfortable

This makes interesting reading for restaurateurs!

These figures clearly show that the acoustic environment has a significant impact on the dining experience of their guests, which in turn affects their spend and whether or not they return.

Architects and interior designers often assume that the ambience in a busy room is an unpredictable result of the occupants’ behaviour. Yes, we can control the lighting and the temperature by careful design, but the acoustic ambience is much too complicated! So the approach is usually “….let’s just not worry about it and hope it’s ok”. Unfortunately the ‘do nothing’ option usually has a predictable result: The familiar stressful cacophony.

But in fact, there are well-established statistical values for how people will behave, which enable us to accurately predict whether conversation in a room will be peaceful or painful.

And there’s more good news: adding acoustic absorbers are twice as effective for human speech as for inanimate noise sources. This is because a virtuous circle is initiated: reduced ambient noise due to absorbers means people speak more quietly, reducing the ambient noise associated with speech and so on. So an investment in acoustic treatment in any room likely to host a crowd is money very well spent.