In 1976, engineers testing the Rolls-Royce/SNECMA Olympus, an afterburning turbojet that powered the supersonic passenger jet Concorde, needed to identify where different components of the engine's noise were originating. The engineers placed 14 quarter-inch condenser microphones spread across the test rig, each connected by a 100-meter cable to a minicomputer, which applied calculated delays to each channel and combined the signals.
It was one of the first practical demonstrations of a method the British researcher John Billingsley had proposed two years earlier, which he called an "acoustic telescope." The underlying principle was older still. Naval hydrophone operators had been using directional arrays to find the bearing of enemy submarines since the First World War, refining the technique further through the Second World War and the Cold War that followed.
Fifty years on, a shrunk-down descendant of that jet-engine listening rig hangs above conference tables around the world. It is disguised as a ceiling tile.
Beamforming, the technology that lets a boardroom microphone follow a speaker walking around a table while ignoring the HVAC hum and a tapping pen, runs on essentially the same physics used to locate aircraft noise sources and, before that, submarines. What has changed is the size, the cost, and the amount of processing packed into a discreet ceiling-mounted enclosure. For anyone specifying, installing, or budgeting for a conference room, understanding what that enclosure is actually doing, and where the physics impose hard limits regardless of the price tag, is the difference between a room that sounds clear and one that sounds expensive.
The Math: Delay, Then Sum
Beamforming works with microphone arrays –or a collection of microphones all working together with a computer to process the sound it picks up. Underlying most beamforming microphone arrays is a calculation known as ‘delay-and-sum.’ Each element in the array is a separate microphone, sitting at slightly different points in space. This means sound from any given direction reaches each one at a slightly different moment. The array's processor calculates that timing gap for a chosen direction, then digitally delays the earlier-arriving signals so all the microphones' outputs line up in time.
What happens next is a straightforward case of wave interference. Sound arriving from the targeted direction lines up in phase and reinforces itself, coming through loudest, while sound from other directions falls out of phase, combines less coherently, and is attenuated, though not entirely eliminated.
The result behaves something like a flashlight beam made of sound, imperfect edges and all. Point it at whoever is talking, and their voice comes through strong while the room around them fades. The direction of that "beam" is not physical; nothing tilts or moves. It is math, recalculated continuously, which is why an array with no visible moving parts can still track a person circling a whiteboard.
The same underlying array principle also shows up in Billingsley's acoustic telescope and in earlier naval hydrophone systems. The implementations differ; active sonar adds transmitted pulses and echo processing that a passive conference-room mic never needs, but the core math of comparing arrival times across an array is the common thread. Boardrooms just replaced jet turbines and submarines as the thing being listened for.
From the Wind Tunnel to the Ceiling Tile
Getting delay-and-sum out of an aerospace test lab and into commercially available conference-room products took decades of engineering and patent work. ClearOne brought a commercial beamforming conferencing system to market in 2012, then in January 2018 announced it had received a patent covering a beamforming array integrated directly into a ceiling or wall tile, rather than housed in a separate hanging fixture.
In September 2019, the company announced a second patent covering a band-limited beamforming array. Per the patent's own filing, it augments the main beamforming microphones with additional microphones that resolve a separate, restricted frequency range outside the primary beamforming process, extending the system's usable frequency response without requiring every microphone to run through the full beamforming calculation.
ClearOne's wider beamforming patent portfolio also became the subject of litigation. In 2017, after receiving a separate patent covering the combination of a beamforming array with acoustic echo cancellation, the company sued Shure, Biamp, and QSC for infringement, naming three of its biggest competitors as defendants at once. The dispute is a useful measure of how commercially valuable the underlying processing had become by the late 2010s, even if it wasn't the same patents described above that triggered it.
That portfolio changed hands entirely in October 2025, when Biamp acquired ClearOne's intellectual property outright.
“ClearOne helped set benchmarks in professional audio, particularly in beamforming microphones and core Digital Signal Processing,” said Biamp CEO Rashid Skaf at the time, b bringing the technology that had once been at the center of patent litigation into a single company's portfolio.
Today the same core idea ships from most major conferencing manufacturers. Ford AV, a national AV integrator, identifies products from Shure, Sennheiser, Yamaha, Audio-Technica, ClearOne, Biamp, and Sony as vendors building beamforming into their ceiling-array lines. While Ford AV provides a useful snapshot of the market, its list reflects the vendors it works with rather than a comprehensive industry survey.
The Room Still Wins: Why RT60 Sets the Ceiling
No amount of processing fixes a room that fights back. The metric that matters here is reverberation time, or RT60: the time it takes for sound energy to decay by 60 decibels after a source stops. Glass walls, bare tables, and whiteboards, standard fixtures in a modern meeting room, all reflect sound rather than absorbing it, which drives RT60 up and speech intelligibility down.
Beamforming can attenuate some off-axis reflections, but it cannot fully undo reverberation from within or near the target zone itself—the walls and table the speaker is sitting at.
Biamp's own room-tuning documentation for its Parlé microphone line puts it plainly: high reverberance "cannot be corrected with electronics," only reduced through physical acoustic treatment.
The company's ‘launch tuning’ software scores a room's measured RT60 on a five-point scale, and its published report cards rate 400 to 500 milliseconds as "good," 500 to 1,000 milliseconds as "fair," and anything over 1,000 milliseconds as "poor" for conferencing performance. A room built more like a lecture hall or atrium can run well past that line and defeat even a well-tuned array. This is the detail that gets lost when beamforming is sold as a plug-and-play upgrade. An integrator can spec the best array on the market and still deliver a room with poor acoustics if nobody addresses the glass and the bare table underneath it.
Steering the Beam: What's Actually Inside the Box
Once the room's acoustics are under control, the array's own processing determines how well it can isolate and track speech. Shure's MXA920 illustrates how far the electronics have come.
The unit packs more than 100 individual MEMS microphone elements to generate up to eight discrete audio beams, which can either track talkers automatically as they move or be manually steered and locked to fixed zones for applications like voice lift, where the room's own speakers reinforce a presenter's voice back into the space. The detailed white paper documents a shift from post-mix to per-channel acoustic echo cancellation, applying echo removal to each of the eight beams individually rather than to the blended output, which cuts down on the artifacts that used to creep in around overlapping speech.
Ford AV describes the same mechanism for its own clients in strikingly similar terms: each element picks up sound on its own, the array's onboard Digital Signal Processor applies delays to line those signals up and reinforce the speaker's voice, and the system keeps recalculating which direction to favor as that speaker moves. Modern arrays layer plenty on top of that: adaptive steering, noise reduction, automatic mixing, echo cancellation tuned per beam, but the same timing principle described above sits underneath all of it, evident even in language written for a systems integrator rather than an acoustics researcher.
Biamp EVP Joe Andrulis, on the patent underlying the company's Parlé line, put the same idea more simply: “Beamtracking enables us to deliver truly extraordinary meeting room experiences.”
What the Room Actually Buys
None of this changes the fundamentals of a good AV spec. A beamforming array is a processor applying array mathematics, delay-and-sum at its foundation, often layered with adaptive or frequency-domain methods, to whatever the room's acoustics hand it, and the room establishes the ceiling on how good that math can make things sound. The manufacturers competing in this space have spent decades turning a technique once demonstrated on a Concorde engine into something that disappears into a drop-ceiling tile, contesting each other's patents along the way. What they haven't done, and can't do, is repeal the acoustics of a glass-walled boardroom.
The next time a ceiling tile in a conference room quietly steers its attention toward whoever starts talking, the moment traces back to a British researcher pointing a bank of microphones at a Concorde engine, and further back still to the naval engineers who worked out the underlying math to find a submarine. The room changed. The math didn't.