Bowers & Wilkins

Case study access

Physical experience

Prototyping and testing product controls

Roles

  • Product designer (me)
  • Prototyping engineer

Scope

Researching, prototyping, and testing the physical controls of Bowers & Wilkins headphones — button placement, gesture zones, and idle wrist ergonomics — to ensure every interaction feels effortless and intentional.

Duration

6 months

Product controls testing

Physical controls prototyping session

The challenge

Getting controls right

Physical buttons and touch controls on headphones are used in contexts where users can't look at the device — commuting, exercising, working. They rely entirely on muscle memory and tactile feedback. A misplaced button means a skipped call, an unintended volume change, or a moment of frustration.

Our goal was to map how users naturally reach for their headphones and design controls that meet them there.

Button placement exploration

Key findings

What we discovered

Idle wrist direction

When hands are resting at the user's side, the wrist naturally rotates inward. Controls placed on the outer cup require an unnatural arm rotation to reach — increasing error rate by 34% in blind tests.

Button differentiation

One challenge we faced was the constraint on button placement—they had to be positioned on the outer earcup. This meant they sat close to the edge, making them harder to locate and press.

Button clustering

We separated the controls by moving the power and ANC buttons to the left side, keeping playback controls on the right for clearer distinction and improved usability.

Process

Prototyping and iteration

We built 3D prototypes to rapidly test different control positions. Participants wore the prototypes during scripted tasks while I observed their natural reaching behaviour.

Each round of tests produced a heat map of successful vs. failed interactions, directly informing the next prototype iteration.

Ergonomic testing session

Key Insights

Optimising placement

23 participants tested three prototypes with varying button sizes and placements. One key insight was users’ initial touchpoint when wearing the headphones—most naturally reaching for the bottom edge of the earcup rim. Another finding was that larger buttons improved success rates but introduced a less stable, “floppy” feel. Ultimately, we identified an optimal size that balanced accessibility with precision.

Post-launch validation

What reviewers said

Positive
"Physical controls are the same as the Px7 S3, which offer a better balance of buttons per cup than the previous gen Px cans, with the power/bluetooth and ANC buttons on the left ear cup and play/pause and volume +/- on the right. The play/pause button also gets a textured surface and being smaller than the two buttons flanking it, makes it much easier to distinguish by feel. Overall I found these revised controls much more intuitive."

audiograde.uk

Andrew Simpson

1 / 4
Positive
"The revised button layout, which reshapes the volume up, volume down and play/pause buttons to improve their tactile interaction and relocates the power button to the left-hand earcup to make physical control easier."

cepro.com

Robert Archer

2 / 4
Mixed
"While I'm not wild about physical buttons, they're least problematic when they're easy to tell apart when fumbling with your fingertips. The multifunction button on the right ear cup is ridged, so there should never be a situation where you hit the wrong button if you take a minute to feel it."

Independent review

Contributor

3 / 4
Critical
"Eagle eyes will notice there have been a few tweaks to the button layout and design compared with the Px8. The control buttons have shrunk on the back of the right earcup, especially the play/pause button. We found the main controls a little on the small side, especially when you consider their location, right on the slim inner edge of the right earpiece. This can make them slightly fiddly to locate and press."

Audio Journal

Staff Review

4 / 4