Intelligent sound masking
Quell adds exactly the sound that makes speech unintelligible — and adjusts it on its own the moment the room gets busier.
… the account number ends in 4 7 1 9, and Monday’s diagnosis was …
You catch every word.
The problem
At the sea you relax because the wash of the waves blurs the voices around you. You hear that someone is talking — not what they are saying.
In the office that wash is gone. Keyboards are silent, printers live next door, phones no longer ring. What remains is a room where every word from the next desk arrives perfectly sharp.
~4×per second
Micro-pauses in speech — intelligibility hides inside them
#1complaint
Intelligible speech is the most common open-plan complaint
GDPRduty
Overheard conversations are a data-protection risk, not a nuisance
Two costs, every day: focus you lose — and a confidentiality risk you never see.
The principle
Sound masking does not drown speech out — it fills the gaps your brain uses to assemble meaning.
Intelligibility lives in the consonants and in the short pauses between them. Lay a gentle, even bed of sound across exactly that range and speech loses its edges. You still hear that someone is speaking. You simply cannot make it out.
That is why a room with Quell does not feel louder — it feels calmer. The measured level goes up; the distraction goes down.
Simplified illustration of the principle: the masking curve sits where intelligibility is formed.
The form
No grille, no visible driver, no box that announces itself.
There is no loudspeaker inside. There is a surface transducer. It couples to whatever the device stands on — desk, sideboard, acoustic panel, glass pane — and makes that surface vibrate.
The sound then comes from the whole surface instead of a single point. It spreads evenly, has no locatable source, and there is nothing to mount and nothing to wire.
The surface radiates, not the device. Nothing in the ceiling, nothing in the wall.
Diffuse coverage instead of a point source — no “it is louder over here”.
Set it down, switch it on. No electrician, no building work.
The difference
Most masking devices play a file. Quell measures the room continuously and adjusts to it.
Runs entirely on the device. No cloud, no internet needed.
Follows how loud the room is, continuously.
Tells its own sound apart from the room’s.
Reads the true ambient level.
Moves the volume smoothly — no pumping.
The room changes — and the loop starts again.
When the room gets lively, Quell lifts the masking level gently. When it settles, Quell eases back. You never notice the regulation — you only notice that it stays comfortable.
Your own volume stays the reference point: you set how loud it should generally be, and how much room the device has to move around that.
Privacy-Glass
Glass is the weakest point of every confidential room. Quell makes it the strongest.
A window pane vibrates along with the speech in the room — which is precisely what laser and contact microphones exploit from outside.
In Privacy-Glass mode Quell measures the pane on the device itself, finds its resonances, and places the masking on exactly those frequencies — through the glass.
Every window resonates differently. Quell analyses the glass in front of it, not an average.
The energy goes into the exact resonances that carry speech outward.
The effect lives in the pane — not in the meeting room.
Soundscapes
From neutral masking noise to natural ambiences — or your own material.
The signature blend. Tuned to speech frequencies, easy to live with for hours.
Classic noise profiles, from bright and neutral to deep and soft.
Natural ambiences for reception, waiting areas and lobbies.
Bring WAV or MP3 onto the device through the app or over USB.
Every room sounds different. Tune the balance to hard surfaces, carpet or glass — right in the app.
Hz
On request Quell appears on your computer as a drive. Copy sound files in, rename them, reorder them — no app required.
The app
Quell Control Center finds your devices over Bluetooth, secures each with a PIN, and controls all of it — offline included.
Fine steps, or jump straight to a preset.
Change the sound and shape it to the room across eight bands.
Switch the automation on or off and set how far it may move.
Install new device software straight over Bluetooth.
A wizard walks you through single device, mesh and Privacy-Glass.
German, English, French and Spanish — like this site.
Free to download
The app includes a demo mode — you can explore all of it before a device ever reaches your desk.
For teams and floors
One device works alone. Many devices work together.
Up to 20 devices form their own radio network. One coordinates, all the others keep running independently. Set it up once — the floor stays in step.
For larger estates the web console shows every site, level and state in real time — and rolls firmware or new soundscapes out to single devices or whole meshes.
Bluetooth control and the adaptive loop always work — network or not. The cloud is an option for fleets, never a requirement for operation.
Where it earns its place
One device, five very different reasons to put it down.
Win focus back
In open plan, intelligible speech is the single biggest distraction. Quell takes its edge off without filling the room.
Discretion at the desk
Reception and waiting area are often a few metres apart. Quell keeps names and diagnoses where they belong.
Privacy in the branch
Advisory conversations and account details in an open branch need an acoustic screen.
Privilege is an obligation
Client conversations must not reach the corridor — not through doors, walls or windows.
Calm as part of the brand
Lobby, reception and breakfast areas feel calmer and more considered when conversations do not carry.
Engineering
Firmware, app and cloud come from one team and are maintained together.
Prototype status: devices are verified on real hardware. Series certification and market approval are in preparation — ask us for the current state.
Contact
Describe where it is too loud or too open. You get a straight assessment back — not a sales sequence.