The sound of safety: why audio needs the same care as contrast

You open an app and a video starts with the sound on. For most people that is an annoyance: a swipe, a mute, a small sigh. For an autistic person already carrying a full sensory load, it is not an annoyance. It is pain, arriving with no warning.

The industry's answer is a volume slider. That is not accessibility. It is a mute button on a design decision nobody asked for, and it puts the work of protection on the person already overwhelmed.

I am an autistic founder. I have spent years building software for neurodivergent people, and sound runs through all of it, because sound runs through my own life. For twenty-five years, music at the right level has been the difference, for me, between drowning and breathing. I know what sound does to a nervous system, because mine has never been neutral about it. The same is true for millions of people, and for many of them the relationship is the opposite of mine: sound is not an anchor, it is an assault.

What sound actually is

For a neurodivergent nervous system, sound is never background. It does one of three things: it regulates you, it carries meaning, or it hurts.

Which one it does depends on the sound itself, and on its level, its texture, whether you expected it, and the state you are in. The same frequency that grounds one person on a Tuesday overwhelms another on a Wednesday. Sound that arrives suddenly costs more than sound that arrives announced. Sound you cannot predict is not neutral, even when it is pleasant.

A volume slider covers one of those things, loudness, and only after the fact.

What we built

On our music pillar, Diverse & Deep, we built something different: an aural sensory profile. You set it yourself, and it travels with you between visits and across products. It holds how you hear and listen: the levels that work for you, the frequencies and textures that regulate you, and the ones that overwhelm you. It is sensory, not medical. Never a diagnosis, never read from your behaviour, and never shared with an employer or anyone else.

Then the products respect it. No sudden audio, ever. Every sound waits for you to ask for it. Levels stay predictable. Nothing uses sound to alarm you, because a sound that startles is not a notification, it is a trigger.

What changes in design practice

Once you hold an aural profile, sound decisions stop being aesthetic decisions and become consent decisions. Autoplay without consent is no longer a growth tactic. It breaks a stated need. A notification sound is no longer chosen by a brand team chasing delight, because delight is personal, and the same ping that delights one nervous system startles another.

The industry has been through this shift once already, with contrast. We learned that low contrast is not a style choice for a low-vision reader. It is a locked door. Sound is the next locked door, and most products have not noticed, because sound does not show up in a screenshot. A product can look flawless in a review and still be unusable, or harmful, to a sensory brain. Nothing in the design review fires an alarm, because alarms make sound, and sound is the thing being ignored.

The floor, not a feature

The aural sensory profile is part of the accessibility standard we hold everything we design to. Not a feature of one product: the floor for all of them. Wherever something we build has sound, music or listening in it, the person's aural profile is already there, ahead of the design.

None of this is technically difficult. A profile is a settings file. Respecting it is a handful of rules about when audio may play. What is rare is not the code. It is the conviction that a person's ears are a stakeholder.

Design sound like it matters. To a sensory brain, it always did.