Welcome back, aspiring cyberwarriors!
Today we are looking at Long Range Acoustic Devices, or LRAD. They are often described as mysterious “sonic weapons,” but at their core they are highly directional acoustic systems designed to project energy with precision. Like any focused emitter, what matters is how the signal is generated, shaped, propagated, and ultimately received by a human target. For SDR practitioners, this topic should be particularly interesting. LRAD is not magic and it is not science fiction. It is applied physics, beamforming, and power management, operating in a part of the spectrum we do not associate with signals intelligence. To understand LRAD you need to understand how energy is concentrated and why small changes in distance or angle can drastically alter outcomes.
In this article, we break down how LRAD systems are built and why they behave the way they do. We also examine their reported use in Venezuela in January 2026 and place that event in context alongside the historical use of LRADs against protesters worldwide. In Part Two, we shift focus to the physiological effects of high-intensity acoustic exposure and discuss what practical countermeasures exist against LRAD systems.
Finally, in Part Three, we take the theory and analysis one step further by building our own simplified LRAD-style system.
Technical Principles and Development
An LRAD is essentially a focused, high-powered loudspeaker array. Rather than blasting sound in all directions, the system uses many emitters arranged and phased so the acoustic energy beams forward in a narrow cone. This produces two principal modes of operation.
In voice or communication mode, an LRAD delivers clear and intelligible speech over hundreds of meters and, in some cases, several kilometers. This allows operators to issue instructions or conduct hailing in environments with high ambient noise or over long distances where conventional loudspeakers are ineffective.
In deterrent or alarm mode, the device emits a high-energy, high-frequency tone, typically in the 2-4 kilohertz range, that is extremely uncomfortable and can induce pain or disorientation at close distances. Due to the highly directional nature of the acoustic array, these effects are concentrated within a narrow beam, with sound intensity dropping sharply just a few degrees off-axis.
When operated at maximum output, LRAD systems can produce sound pressure levels far exceeding commonly accepted thresholds for pain and hearing damage. This makes them effective tools for long-range communication and area control, but also introduces significant risk if they are misused, improperly deployed, or applied at close range.
LRAD technology was born out of a practical need. After the USS Cole bombing in 2000 the U.S. Navy sought a reliable way to hail and warn small craft at distance, and American Technology Corporation (now Genasys) introduced the first LRAD in 2002. The engineering is straightforward acoustic physics. It concentrates sound energy into a beam to increase range and intelligibility. The marketing may call them communication devices, but their deterrent tone has led to both legitimate safety uses and controversial crowd-control applications.
Use in Venezuela
In January 2026, during the high-profile operation that resulted in the capture of President Nicolás Maduro, multiple eyewitness accounts and public statements asserted that U.S. forces deployed a sound-based weapon as part of the assault. In interviews that circulated widely on social media and in international news, a Venezuelan security guard described an intense and overwhelming acoustic effect that incapacitated local forces.
It induced severe pain, balance disruption, and collapse, just as helicopters and troops were engaging defensive positions around Caracas.
Some reports of the event specifically used the term “sonic weapon” or “sonic attack,” and U.S. political figures later referred to the use of advanced, undisclosed technologies in the operation itself, contributing to the narrative that a novel acoustic capability played a decisive role in neutralizing resistance. These accounts have been widely shared in media stories that emphasize the dramatic nature of the technology used in the raid and its impact on the defenders.
Historical Use Against Protesters
LRADs have been used repeatedly by police and security forces around the world in crowd-control settings, and those deployments have produced both documented injuries and legal challenges. Agencies often assert that LRADs are communication tools, but in practice they have frequently been used to deter or disperse crowds. Observers and victims have reported ear pain, loud ringing (tinnitus), headaches, dizziness and in some cases barotrauma or long-lasting hearing damage following close-range exposures. Notable incidents include the 2009 G20 summit in Pittsburgh where a truck-mounted LRAD was aimed at a crowd and people reported severe ear-related injuries, the Occupy Wall Street protests where handheld LRADs were used in short bursts, and incidents during the Ferguson and other protests where prolonged use of alarm tones near crowds produced complaints and medical follow-ups.
In 2025, a high-profile incident in Serbia occurred during mass anti-government protests, where demonstrators reported exposure to a powerful and unexplained sound. This led to allegations that LRADs or other acoustic devices had been deployed. Subsequent investigations and independent audio analyses were inconclusive, and Serbian authorities denied using such devices during the protests, while later confirming that LRAD systems had been procured by the state.
In Hong Kong, police mounted LRADs on armoured vehicles and deployed them during major protest confrontations, including the siege of the Polytechnic University. The devices were used to broadcast warnings. Journalists and demonstrators reported exposure to high-intensity sound that they described as disorienting.
In New Zealand, police confirmed the use of LRADs during the 2022 Parliament-related protests, primarily for long-range communication and crowd management.
The legal response has expanded in parallel, particularly in the United States. Civil rights lawsuits and subsequent court rulings have prompted some municipalities to prohibit the use of high-pitched deterrent tones, mandate minimum standoff distances, and impose restrictions on indiscriminate deployment. In parallel, human rights organizations have called for independent health studies and more rigorous oversight frameworks. From a medical and evidentiary standpoint, LRAD exposure is considered a plausible contributing factor when individuals report acute auditory symptoms following encounters with security forces. However, each allegation still requires careful and case-specific analysis.
Summary
LRAD’s significance lies in the application of familiar concepts such as directionality, beam shaping, and energy concentration to sound rather than to radio-frequency systems. By focusing acoustic energy into a controlled beam, LRAD translates principles commonly associated with electromagnetic systems into the auditory domain. As these systems migrate between military use, law enforcement, and the management of public spaces, they complicate the assumption that communication technologies are inherently neutral. Tools intended to extend range and intelligibility can become coercive when output levels increase and operational safeguards erode.
Source: HackersArise
Source Link: https://hackers-arise.com/long-range-acoustic-device-lrad-part-1-from-navy-origins-to-venezuelas-2026-raid/