The clinking of glasses, the chatter of patrons and the selected music are all essential to a vibrant dining experience. This experience is, other than that of the food, is one of balance that is often found tipping towards the more noise-related end of the scale. An enjoyable experience does not include people having to raise their voices above one another, or by missing out on a conversation because they cannot hear. This effect is called the Lombard effect, or ‘Café effect’ where groups unconsciously raise their voices over others so that they can listen to. This effect continues to happen until the room reaches a dreadful cacophony.
There is now greater access to online reviews that can be brought up in seconds on your smartphone. There are even Crowdsourcing apps (check out SoundPrint) that allows the user to measure the loudness (in decibels) and categorises how loud it is. You will also find those food critics discussing how ‘noisy’ a restaurant is, as over time they have cranked up the volume. Potential customers now have these ‘tools’ to help avoid eateries that do not match what they want as an experience, and this could be potentially your restaurant(s)!
When it comes to noise and sound, this is your ‘acoustic environment’. When Bluebell got hold of iKoustic to see how a new and thriving restaurant could create a better acoustic environment, we walked them through what is possible, and the path to dimming the cacophony.
Noise in Restaurants.
In open-plan restaurants like Bluebell, designers are creating a living, breathing space. These feature kitchens that blend into dining areas and have high ceilings that expose the ducting of air conditioning with light fixtures that extend the reach of the room. They are also made up of hard-finished furnishing and surfaces to appeal to the current boom in minimalism. Not only this, but the hard furnishings are easy to clean, another area of management for making sure your restaurant is in tip-top shape. But, what these mean for your acoustic environment is far less manageable without professional input and a series of effective resolutions in place.
There has been a rise in studies of noise, music, taste and experience in hospitality in recent years; it is a complete sensory experience combined with social interaction. It is our vision, hearing, taste and smells that all become excited. The rise in noise found in restaurants has steadily grown year on year. On some occasions, these measurements have been found at damaging levels to our sensitive ears, let alone at levels that are comforting for allowing conversation; an essential part of the social element of dining out. The Guardian has found that
“The dB levels at many restaurants far exceed this pleasant thrum [between 55-65dB]. The average sound level recorded in UK restaurants on Soundprint, taken between 6pm and 9pm, is 79dB. “I’m sure many of those are above 80, and I’m sure some are above 85,” says Scott. “It’s really loud for conversation.” In 2017, the UK charity Action on Hearing Loss (AoHL) found that noise levels in some well-known chains, such as Patisserie Valerie, topped 90dB on busy evenings. That’s the equivalent of munching your croissant next to a lawnmower or motorbike.”
and if you are finding these kinds of levels at your restaurant, these would most definitely land complaints and critiques pointing this out.
There are possible connections between the sound intensity and the drinking of alcohol, but when combining this with food, it comes up as the second most common complaint in restaurants. Different intensities in background noise may even affect what you taste. PRI’s study on the impact of sound on taste highlights the following.
“Researchers asked participants to eat chips and cookies while listening to white noise at either high or low volumes, or in silence. They found that the eaters perceived saltiness and sweetness as less intense when they ate the food in the presence of loud background noise, in contrast to when they ate it with quieter or no background noise.”
The fascinating part of what we are beginning to discover is that there are certain foods that taste best or worse at specific sound intensities, with the aviation industry tailoring their meals to match the loud roar of jet engines, to the average dB levels of restaurants revamping their menu for the different intensities.
Reverberant spaces are open and reflective. They allow everyone’s conversation, the clanging of pots and pans in kitchens and the background music to all meld together as intrusive background noise. It is the introduction of more absorptive surfaces that help to control this ‘bouncing around’ and reinforcement of perceived amplitude of the sound. Acoustics Today has highlighted that
“The higher the average absorption coefficient, the more sound will be absorbed by the room surfaces. So, if a restaurant is to offer a quiet, subdued environment, where people can talk quietly, it is important to use larger amounts of sound-absorbing material on the available ceiling and wall areas. If a venue is to have a more “energetic” feel, less sound-absorbing material should be used, but that material should be used in strategically placed areas that have the potential to get louder than others”.
It is not that that whole room would require absorptive materials; this would not create a vibrant balance and would be more like dining in an anechoic chamber! The aim is to place them evenly across walls and ceiling so that there is a more even surfacing that will absorb the sound energy.
As we mentioned, it is about the balance of what you want for your restaurant’s atmosphere and experience. These will determine the amount of internal acoustic treatment you will need to create it.
Bluebell has had a successful start with their food, but after receiving a few reviews about the noise at their restaurant, especially on busy evenings, they got in contact with iKoustic. With an open-plan dining space made up of glass partitions, hard finished walls and floor – this resulted in a very challenging and reflective environment. Both at lunchtimes and evenings, the noise reverberated and caused massive disruptions to the conversation of others.
The team at Bluebell wanted a complete design that would complement their current interior design and colour scheme, so we needed to work together on finding a solution that would do so. We went to visit them to present our Note™ range on-site to show them the possibilities of not only matching their surface colours but also their light fixtures and cooling fans. We brought along our ‘mood-board’ to collaboratively choose the right tone and mood of the room by comparing these internal features with our available options!
We took a simple projection of estimated reverb time by using a modelling of the room. These take what is called the ‘absorption coefficients’ of the surfaces, how absorbant a surface is in other words and calculates an estimated reverb time. This reverb time is how long it takes the sound to decay. You can discover more about reverberation by pressing on our icon below.
Dimensions of the space
Length – 8.1m
Width – 4.9m
Height – 4m (top of pitch) 2.4m (bottom of the pitch.)
Estimated Reverberation Calculations
From these dimensions, our calculations were estimated at a reverberation time of 3.3 seconds, much too high for a restaurant with receiving even modest levels of speech intelligibility. We would usually aim between 0.8 – 1.2 seconds. We proposed that at least 17.3m2 of Class A sound absorption would be needed to be at the levels between 0.8 – 1.2 seconds. This would need applying across the wall and ceilings space for best coverage.
To present our proposed finished look, we provided them with our visualisation service. 2D drawings would help display the layout of our Hexagonal Soft Note™ panels wrapped in Camira Cara Fabric. The choice of using Hexagonal cuts in various sizes and colours not only creates a visually stimulating space, but the shaping also allows more space to add sound absorption in these areas, just as bees do with its honeycomb structure.
From the measurements, we then created a 3D scale of the room with its current colour scheme and implemented our approved Note designs with the addition of Soft Note™ Pro on the ceiling, evenly spaced. In this process, we include all fixtures and furniture that we closely match to assure best representation.
All ceilings panels were evenly spaced to provide the best performance possible, and this is important when reducing reverberation as there is more available absorptive surfaces.
Our installation team installed the panels as direct adhesive fixing so as not the impose on the room or interfere with the fixtures. The Hexagonal shaping in these colour gradients created an off-beat style of imagery but at no time feeling out of place. The different sizing and placement also allowed various shapes to appear from the original wall that we think creates a stimulating visuals.
There texture of the Hexagonal Soft Note™ panels comes from the Camira Cara Fabric wrap, and this gives them more depth instead of a solid colour wrap. An approach that both us and the team at Bluebell love.
The final sound was vastly improved and the ‘feel’ of the room was undoubtedly more controlled, we now await those reviews after a busy period from customers that congratulate them on the improved acoustics of the room!