In times of business globalization, criminal and terrorist activities have increased. Furthermore, the gap between rich and poor continues to widen with more and more countries affected. The peaceful co-existence worldwide is threatened and increasingly violence is reported.

The “Institute of Fire Safety and Safety Technology“ of our company Hügin Group International has managed to develop a highly efficient system. In close collaboration with Professor Dr. J. Herbertz1, a leading and awarded scientist in acoustic, noise and vibration engineering, we have developed and approved a pneumatic transducer. After the death of Prof. Herbertz the system “Herbertzhorn” was legally protected as a trademark and concretized in the following fold concept „AS2D“ (Acoustic System of De-escalation and Defence)

The various possible modes of operation of this special defence system by:

  • internal security
  • protection of critical infrastructures and borders
  • Maritime piracy
  • protection of large-scale facilities allow innovative protection options.


New models of non-lethal security systems became necessary to avoid the mandatory use of lethal weapons against unrest in crisis areas.

Applications and variations of the system:

Internal Security

The AS2D is a new operational tool that considerably extends the ‘instrument box’ of the police. The use of it is substantially less harmful than the use of firearms and thus it is an instrument particularly suitable to the requirements made of the state to use appropriate force. Equipping the security authorities with the AS2D will clearly increase and improve the operating options in difficult situations and lead to an improvement of the quality of police ability to control situations.


A phenomenon that is well known in many cities: On certain days of the year or on the occasion of certain political events there can be violent demonstrations that are associated with equally violent affrays, riots and looting. This then leads to violent confrontations between security forces and the rioters. Non-participants are often involved in these confrontations, the consequences of which can be severe physical injuries, including death, and extensive material damage. In these situations the police often use water cannons in order to keep the rioters at a distance. The use of the AS2D is a clear alternative to the use of water cannons. Unlike the water cannon the AS2D does not require ‘time out’ to refill and is continuously ready for operation. The use of the AS2D thus serves to clear the streets and public places and keep them clear of rioters and criminals as well as keeping both at a distance.

The effect on violent troublemakers from the use of several AS2D, as with water cannons, can be increased according to operating conditions.


Another alternative is the use of the AS2D in hostage and threatening situations in enclosed spaces or out in the open.

With the help of the portable variant it is possible to set up a AS2D in the immediate vicinity of the hostage takers.

Unlike with the use of the Herbertzhorn in the case of the previously mentioned violent affrays, the use of the AS2D in close proximity will come as a complete surprise to the hostage takers. The sound and the volume of the sound will cause shock and disorientation and incapacitate them. This effect can be used by special units of the police for an assault on the hostage taker without killing him. The sound and volume induce shock, disorientation and inability to act. The effect of this may enable special units of the police to intervene in a hostage situation without any loss of life.

In hostage and threatening situations the unexpected use of the AS2D compels perpetrators in the vicinity to stop their activities or at least makes it very difficult for them to continue these activities, as they may be disoriented, in a state of panic, confused or distracted.


Cabin protection against gunfire

We can also, on request, equip the vehicle with VR4 or VR 4+ (Euro Standard DIN EN 1522-1; ballistic level) to protect it from handguns and other small weapons and explosives of a certain size. The protected area of the cabin: roof, floor, windscreen, side doors. Possible weak points in the doors are reinforced with overlapping protective material.



We deliver the AS2D complete systems (incl. vehicle) or partial systems (without vehicle). In the latter case the complete system can be delivered and mounted on-site on the desired vehicle.

Fahrzeug aufgesetzt.


Protection of Critical Infrastructures

The current worldwide security situation requires national and international observation and planning guidelines in order to protect critical infrastructures and border protection.

Especially in times of international crises it is important for the joint elaboration to ensure the proper functioning and protection of important government and private institutions.

For example, nuclear power plants may be mentioned here, together with oil refineries and other energy and water provision facilities. Other potential targets include numerous state and private political, economic and social institutions. It is precisely in times of numerous international crises that undisturbed functioning of important state and private institutions is important for working out national and International solutions. In this sense protection of such property becomes increasingly important.

With our AS2D we are also able to protect objects far before the use of firearms. “Sound walls” are initiated around the jeopardized objects by manual operation or by means of electronic monitoring systems to prevent a planned attack circular around the object to be protected.

Strategically the AS2D fulfils a dual function in property protection. It has a considerable effect on the perpetrator (see above), foils, disturbs, interrupts and complicates communication among the criminals and enables the security forces to take appropriate counter-measures.  

At the same time the AS2D has come to the attention of the people and is thus developing a warning and protection function.

Border Protection

The basic protection consists of at least 2 AS2D. e.g. to secure a checkpoint with an acoustic power of at least 27,000W.

Per high performance compressor-unit up to 8 AS2D with an acoustic power of 108,000W can be operated on a defence line of approx. 250 m. Per plant room up to 4 high performance compressor-units can be built in, with a max. acoustic power of 432,000W and a defence line of approx. 1,000m.



Maritime piracy

With this system the AS2D is firmly attached to a vessel. e.g. speedboat, coastal patrol vessel, corvette or frigate. Instead of a AS2D several defence systems are combined and controlled from the bridge of the ship.



As module systems (20ft containers) on the Abeking & Rasmussen 25 M SWATH@A&R with at least 3 AS2D:

  • Sound power 40,500 Watt
  • Air consumption 900 l/sec.


As additional installations on marine vessels, e.g. corvettes, frigates etc. with up to at least 8 AS2D:

  • Sound power 67,500 Watt
  • Air consumption 1,500 l/sec.


Protection of buildings and against burglary

  • Protecting schools and shopping malls etc. by supporting the defence system within the structure of the building
  • Protection against burglary in buildings, e.g. industrial facilities, public institutions

The AS2D strategically has a dual function in protecting buildings:

  • Its effect on the perpetrator (see above) is to frustrate, disrupt, interrupt and impede communication of the perpetrators and enable the security forces to take appropriate counter-measures
  • At the same time, as the Herbertzhorn becomes familiar to members of the public, it develops a warning and protection function