UX sound design can make – or break – a product experience.

I have an air fryer, from a brand that will remain unnamed. It is a solid product, overall - it works as intended, and is great for whipping up crispy tofu, or a quick batch of tater tots. Nevertheless, I find myself avoiding using it whenever I can, and I would hesitate to recommend it to a friend.

The reason for my reluctance is simply the awful sounds it makes.

Virtually every interaction I have with this air fryer – scrolling through baking modes, setting the temperature, etc – is accompanied by a piercing, hair-raising beep. This beep occupies a frequency range and loudness level usually reserved for emergency alerts, with no option to turn it off or even lower the volume. When it is done cooking, it gives this same beep ten times, over a duration of fifteen seconds, during which I find myself hoping against hope that each beep will be the last. The sound design is bad enough to render an otherwise perfectly good product deeply unpleasant to interact with.

Why does it sound like this?

It didn’t have to be this way. Sound is a powerful tool for product designers when used responsibly. It provides functionality, feel and, when calibrated just right, even joy. But getting there requires thoughtfulness, intention, and a deep understanding of how users and customers interact with your product.

Sound Makes Products Feel Better

Do you remember this sound?

I remember it, even though I was five years old when Windows 95 launched. It’s a brief sound, but in a cultural landscape where technology is suffused into the fabric of our daily lives, these small audio cues make a big impact. But this particular sound is notable for its unique origin – it was composed by Brian Eno, the sonic mastermind behind David Bowie’s Heroes and Talking Heads’ Remain In Light and the godfather of ambient music. In a 1996 interview with SFGATE, Eno describes the process for creating the sound, which might sound familiar to anyone working in sonic branding:

“The thing from the agency said, ‘We want a piece of music that is inspiring, universal, blah- blah, da-da-da, optimistic, futuristic, sentimental, emotional,’ this whole list of adjectives, and then at the bottom it said ‘and it must be 3 1/4 seconds long.“ said Eno. “I thought this was so funny and an amazing thought to actually try to make a little piece of music. It’s like making a tiny little jewel.”

Startup sounds have proven to be effective sonic cues for devices with longer boot-up times, such as computers and gaming consoles. As we discussed with Netlifx in a previous installment of this series, by placing these sounds in front of compelling experiences, users build a natural affinity for them and begin to associate them with everything that makes your product great. These cues summon instantaneous, if subtle emotional responses - for example, consider how you feel when you hear this sound. This makes these sonic cues incredibly valuable, with the potential to serve double duty in marketing and content, as brands like Netflix and Xbox demonstrate.

However, as always with UX sound, context is everything. While branded startup sound is effective for some products, it is not universally applicable. Take mobile applications; Apple’s developer guidelines explicitly discourage developers from using the app launch screen as a branded moment, stating that the launch screen “isn’t an opportunity for artistic expression” and that its sole role is to “enhance the perception of your experience as quick to launch and immediately ready to use.” This is good advice - branded sounds should never add unnecessary friction to an experience. Like the Hippocratic Oath, the first rule of UX sound design is “Do no harm.” If branded sounds contribute to sonic clutter, make your product seem less responsive, or waste user’s time, they will only build negative associations (see my above complaints about my air fryer.)

So how do you find the right moment for branded UX sounds? By putting yourself in the shoes of users to understand their needs. To create branded sounds for Instacart, we investigated the user experience to find the perfect moments. We landed on Celebratory sounds reserved for interactions that were infrequent and unambiguously positive. These moments gave us license to use sound more expressively without being obtrusive or detrimental to the core functions of the app. We also developed a tiered system for certain UX sounds that allowed them to scale across three energy levels – Mild, Medium and Spicy – to ensure that Instacart would always have the right energy level for each moment.

When creating sounds for the PayPal sonic ecosystem, we took a completely different approach. For this brand, we wanted to reinforce the two central behaviors of the PayPal experience – paying and getting paid. Yuta Endo, Creative Director at Antfood and creative lead for the PayPal sonic brand, describes the process for scoring these moments:

“While a transaction may initially appear deceivingly lengthy, encompassing various stages such as initiation, information exchange, payment authorization, and post-transaction support, the ‘paying’ and ‘getting paid’ is the most crucial”, says Yuta. “Sound evokes profound emotional responses, as it intertwines with our memories, moods, and experiences. Sound can succinctly add both clarity and delight, and the accumulation of these small joyful moments strengthens the connection between the buyers and sellers, as well as the users and the brand.”

This element of human connection was key to our creative direction. Our goal was to create sounds that would be useful and intuitive for moments of transaction, without losing a human or emotional component.

“The phrase ‘transaction without transactional’ was pivotal in our approach”, explains Yuta. “We aimed to ensure that the sounds not only functionally conveyed a sense of a “transaction,” but also evoked emotions beyond the stereotypical coldness associated with transactions. Thus, instead of relying on coin jingling or cash register sounds that are common in the financial technology space, we leaned into upward movement, shimmery timbres, and intriguing tactility to achieve the essence of a ‘transaction’ in a way that feels warm and authentic.”

Sound Makes Products Work Better

There is more to sonic UX than mood and brand. Sound can greatly increase the functionality of products, adding real value to users. Sound can be used to manage attention, provide confirmation, and guide behavior. As technology advances and becomes more enmeshed in our daily lives, the need for UX sounds grows, as do the complicated considerations involved in creating compelling and functional UX sound experiences.

One great example of this dynamic is the field of automotive sound, where technology is rapidly changing how we drive, and the sounds we hear while driving. Sound has always been top of mind for vehicle designers, with an incredible amount of time and energy being invested in the actual physical sounds a car makes. Engineers fuss over the sound of car doors closing, selecting physical materials with an eye towards making the impact feel substantial and luxurious. Car enthusiasts are known to obsess over engine and exhaust sounds, and manufacturers of performance vehicles such as the Ford Mustang meticulously craft the physical engines of the car to meet these expectations, and have even (controversially) piped artificial noise into the vehicle cockpit.

But with recent advancements in driving technology come new needs for sound, often with critical safety functions. Electric engines are virtually silent at low speeds, leading regulators to mandate artificial engine sounds that alert pedestrians to approaching vehicles. The sounds manufacturers have developed to fulfill this requirement range from minimal and functional to fantastical and expressive, with some auto makers even teaming up with world-renowned composers to create these sounds. Autonomous and semi-autonomous driving also create new opportunities for sound. For systems that alert drivers to potential hazards, directional sound can be used to orient driver attention to potential risk factors more quickly. Sound cues also play an important role in alerting drivers to when they must retake control of the vehicle, a critical safety function.

These kinds of functional sounds tend to fall into two broad buckets. Notification sounds orient user attention and alert them to critical information. Feedback sounds, on the other hand, respond directly to user inputs and help to guide behavior. Creating effective notification and feedback sounds requires in-depth knowledge of the user experience, which often can only come from getting hands-on and putting yourself in the shoes of users.

To create these sounds for Instacart, we experienced the app from both ends, by placing an order as a customer and signing up as a shopper to go on a real-life shopping run. We were struck by the complexity of shoppers’ work, the many demands on their attention, and the need for timely communication with customers. These communications often entail tasks like taking pictures of shelves and navigating replacements, all of which require real-time customer feedback to keep things moving. Add to this the ambient noise and music of the in-store environment, managing multiple orders at once, and the cognitive demands of driving and navigating, and you have a huge potential for sensory overload.

Because communication was so important, unique notification sounds that could facilitate interactions were crucial. These sounds would have to be emotionally neutral, appropriate for positive and negative interactions, while still building on the sonic brand DNA. They would have to capture attention without being irritating and cut through a wide range of background noise.

We also developed feedback sounds to confirm interactions and, where necessary, alert users to mistakes or errors. These sounds would need to be subtle and intuitive, providing feedback without getting in the way.

Ultimately, we left Instacart with a flexible toolkit of future-proof UX sound variations that could live on as the product grows and evolves.

Sound Makes the World(s) a Better Place

What does the world of your product sound like? What kinds of sounds should users encounter in your ecosystem, and how should they make them feel? Few designers would describe their ideal soundscape as stressful, anxiety-inducing or grating, but this is exactly where some end up due to a lack of thoughtfulness or respect for listeners.

Take hospitals, where the proliferation of loud, dissonant, anxiety-inducing alerts has created a noise pollution crisis with measurable negative health effects. The constant din of alerts and notifications gives rise to a phenomenon called Alarm Fatigue, where nurses are inundated with so many sounds that they are unable to separate signal from noise and end up missing important alerts. Alarm Fatigue is considered a major safety hazard, and has been frequently studied, including one report that found that nurses hear about 771 alarms per day on average. The constant noise also has adverse health effects on patients, as noise pollution itself is associated with increased activity in the stress pathways of the Amygdala, which can lead to cardiovascular and metabolic diseases. Stressful noise can interfere with recovery and increase the likelihood of negative health outcomes for patients. The adverse effects of noise are not limited to the hospital room—in the United States, the Environmental Protection Agency regulates noise pollution under the Clean Air Act, citing negative effects such as “stress-related illnesses, high blood pressure, speech interference, hearing loss, sleep disruption, and lost productivity.”

How might hospitals create a better audio environment? This isn’t a simple question, as it involves myriad manufacturers and a complex intersection of incentives that skews the entire field towards over-alerting. But even if we could wave a wand and bring the perfect hospital sound ecosystem to life – what might that look like? How would we balance the multitudes of necessary sonic cues into a coherent and intuitive set of cues that are intuitive and informative while respecting peace of mind? Is there anywhere we can turn for inspiration on what such a system might look like?

This brings us, surprisingly, to Nintendo. It might seem ridiculous to compare the sound world of Nintendo to the sound ecology of a hospital. Nintendo’s products don’t save lives (at least not literally), and the kind of expressive, whimsical sounds that Nintendo uses would be comically out of place in a hospital environment, or most professional environments at that. But, if you take a closer look, their sounds are actually highly choreographed to feel pleasing, intuitive and harmonious. Their sound design is meticulous, highly intentional, and unexpectedly functional, making their games easier and more enjoyable to interact with.

Let’s use a concrete example to (hopefully) make this notion seem a little less ridiculous. In a New York Times article from 2019, Electronic musician Yoko Sen describes the stressful alarm environment during a stay in the hospital. She noticed two concurrent alarms clashing harmonically, with the two tones combining to create a tritone, one of the most harsh and dissonant musical intervals. This phenomenon is actually quite common and is one of the many drivers of alarm fatigue. How would Nintendo solve this problem? By meticulously curating every single bit of audio in the game world to be harmonious with one another. For example, their 2017 title Super Mario Odyssey features a myriad of expressive and melodious sounds. Impressively, every single one of these sounds is carefully tuned to the background music, as well as other sound effects in the game, avoiding clashing and dissonance. Furthermore, because players have the option to customize the music they are listening to, this means that every sound effect in the game has an alternate version designed to harmonize with every score in the game.

This attention to detail and respect for the player’s experience is present throughout all of their major titles. Their 2017 title Legend of Zelda: Breath of the Wild uses rich sound design and dynamic music to both inform and immerse players. Sonic cues confirm that they have picked up an item, alert them to an in-game character with a mission or information to deliver, and let players know they have landed a critical hit. Feedback is even embedded into the musical scores of the game, which responds dynamically to user actions. Taken together, these sounds provide rich feedback that helps teach players how to play the game, guiding their behavior and directing them towards objectives. As Robot-Assisted Surgery and similar advances in medical technology create new UX challenges, there will be a greater need for these types of cues. Ultimately, whether you make games or life-saving medical devices, certain universal principles of sonic UX hold true: pick the right moments, provide the right feedback, respect attention and consider how the system operates as a whole and within the overall listening environment.

Sounds Tells a Story

The kinds of sounds we hear when interacting with a device, a product, or an experience deeply impact how we perceive these objects. Beyond the functional and informative aspects of sounds, there are material and timbral qualities of sound that can help convey what a product or experience is all about. For example, sounds with rich frequency content tend to convey luxury, scope and impact, whereas light sounds tend to feel friendlier, and depending on context can convey ease or simplicity.

Here, again, we can draw insight from game design. To create the sound world of the indie puzzle game Let’s! Revolution!, we considered what kind of world we wanted to create, and how we wanted players to feel about it. Senior Composer Spencer Casey, who helped design and implement the music and sound of the game, explains the process.

“The overall idea was to have it feel tactile and natural. Everything is based on actual recorded audio.” says Spencer. “Instead of digital interface stuff, we decided to keep it all foley. Confirmation sounds all had to have some sort of foley, tactile element. We also paid a lot of attention to footsteps, so there are different sounds whether your character is on a path or off-road, and different sounds for heavier or lighter characters.”

Antfood Amsterdam Composer and Sound Designer, Charley van Veldhoven, was another creative lead for Let’s! Revolution!’s sound. She describes the process:

“We tried to make the user audio experience as satisfying as possible, creating sounds that wouldn’t feel too sharp or too heavy when repeated. For the ‘level events,’ we created short stings that would harmonize pleasantly with the music while conveying the right emotions.” Charley and the team also created unique vocalizations to help tell the story of each character. “One of the most fun processes was changing real-life human voices’ into something otherworldly and unique to the personality of each character! Mitzi, for example, floats around the tiles, light as a feather. We gave this character’s language an airy quality by recreating bird-like sounds with a human voice. We chose not to process these vocalizations too much, as we preferred to give them a natural and lively feel.”

These subtle cues, which in some cases might not even pass the threshold of consciousness to most players, nevertheless have a major impact on how we perceive the game, giving us information on the characters and world.

This kind of sonic storytelling extends far beyond gaming, and can arguably apply to any multifaceted sonic ecosystem. If you asked Google the question “What does the world of your product sound like?,” they would be able to provide an answer. Their Material Design guidelines offer high-level design principles that apply to every aspect of their vast sonic ecosystem. Using the foundations of Informative, Honest, and Reassuring, Google’s guidelines help to foster a cohesive, pleasing and useful sound world throughout a wide array of products and touchpoints. This demonstrates a crucial aspect of creating compelling sound – intention. By keeping an eye towards the experience they are trying to create, and the stories they are trying to tell about their products, designers can make better decisions and create sounds that serve users and create amazing, satisfying experiences.

Creating the perfect UX sound experience

If there is one thing to take away from this article, it is this: when it comes to UX sound, context is everything. UX sounds never exist in a vacuum, and understanding when, how and why users experience sound can make the difference between a great experience and an aggravating one. And though it might seem like small potatoes, these sounds can actually have an enormous impact on our daily lives, and even our health.

So, if you are a product designer, take a minute to think about the sounds you make and the impact you have on users. In doing so, you have the potential to drastically improve your user experience, functionality and bringing joy to your products – ultimately making the world a nicer place to live in.

Colin Coogan, Senior Creative Strategist at Antfood has over 10 years of experience in sonic branding. A lifelong musician, he leverages knowledge of psychology, brand strategy, and music to build comprehensive sonic identities and experiences. He lives in Brooklyn with his fiancé and two unusually large cats.

Part 1: Surrounded By Sound - Why you need sonic branding

Part 2: Surrounded By Sound - Beyond sonic logos

Part 3: Surrounded by Sound - Music as mood magic