How UI Sounds Are Made: A Mouth, a Beer Case and EMF

A menu sound is the most heard sound in a game. Not the boss, not the score, the little confirm tick a player triggers a few thousand times over a playthrough. Which means the brief is the opposite of everything else: interesting once, invisible forever after.

I have built UI for three very different games, and the interesting part is that the sources have nothing in common. One set came out of my mouth. One came out of a case of beer. One came out of electromagnetic fields that are not audible at all until you put the right microphone near them.

1. A mouth, and an apple

The booth was a closet: moving blankets and carpet, blackout curtains about four feet behind me, the mic a foot and a half into the depth of it. An AKG P220 into a Zoom F3 at 96 kHz, 32 bit.

No props. I made the accept and the back with my mouth, practising them first with the famous whistled flute line from the spaghetti westerns in my head as the target for how a tiny melodic gesture can be instantly recognisable. The first take had too much mouth noise, so I ate an apple and did it again. That is not a joke, it is the actual fix.

Two decisions carry the result. A bell cut of about 6 dB at 6 kHz, which dulls the transient and leaves room for dialogue above it. And back tuned down 18 cents against accept, so going backwards sits very slightly lower than going forwards. Nobody notices that consciously. Everybody feels it.

2. A case of beer, for What The Funge

This one started from the other end. Instead of asking what a menu should sound like, I asked what a menu is actually doing to a player, then went looking for a real world action that does the same thing.

Think about the psychological triggers a UI sound is there to pull, then apply them to drinking a beer. Pulling a bottle out of a case. Opening it. Pouring. Putting the empty bottle back in the case. That sequence has a selection, a commitment, a payoff and a return, which is the exact shape of navigating a menu, and every one of those actions already makes a satisfying sound that a human being has positive associations with.

That is what the Lounge Menu of the auto battler is built from. Glass, cardboard, and the specific clink of a bottle going back where it came from.

3. Electromagnetic fields, for Parallel

This was my first HUD work, on the sci-fi trading card game Parallel, and the source could not be further from a mouth or a beer bottle. It is entirely EMF recordings, captured with LOM Electrousi and Priezor microphones, which hear electromagnetic fields rather than air.

So the takes are not of objects, they are of equipment doing things. A strobing multicoloured light. Speaker feedback. Other gear brought into the field of the mic while it ran. None of that is audible standing in the room. It only exists once the microphone translates it, which is exactly why it works for a heads up display: a HUD is a machine talking to you, and this is the literal sound of machinery talking.

The same rig turns up in a short behind the scenes on a sci-fi UI pack, also sourced with the Electrousi and Priezor.

What the three have in common

Nothing, in the source. Everything, in the constraint.

In all three cases the source was chosen for how it wears, not for how it sounds the first time. A mouth sound is warm and human and does not fatigue. A bottle in a case is a noise people already have a good association with. EMF is thin and precise and stays out of the way of dialogue and music. Pick a source that is exciting on the first press and you have built something exhausting by hour three.

The usual game audio export guidance says around -6 dB for effects and says nothing about UI specifically, which is a gap worth knowing about rather than guessing at.

Related

The sci-fi world building those Parallel sounds came out of: Parallel. On building a palette from nothing: foley from scratch. On getting sounds into an engine and mixed: mixing a game in Wwise.