LRAD Product Use
How can I know the decibel (dB) level being broadcast from an LRAD?
Each LRAD model’s maximum sound pressure level (SPL) is specified. Every LRAD features a prominent volume control dial surrounded by a graphic representing Green, Yellow and Red zones corresponding to approximate SPLs. Working backwards from maximum volume (Red zone), the boundary between Red and Yellow reduces the maximum SPL by approximately 6 dB (half the audio output); the boundary between Yellow and Green is approximately 32 dB down from maximum.
How is LRAD’s maximum SPL calculated?
The average (RMS) SPL, at all operational frequencies, is measured with a microphone placed 4 to 8 meters in front of the LRAD (the microphone distance is determined by the LRAD model being measured). The maximum SPL is recorded at the measured distance and the maximum SPL is calculated at 1 meter using the inverse square law: SPL at X meters = (SPL at 1m) – 20 x LOG (Distance).
How loud is an LRAD at 500 meters, 1 kilometer, etc?
LRAD broadcasts follow the inverse square law, which teaches that for every doubling of the distance from the sound source, sound intensity diminishes by 6 dB. Environmental factors can increase SPL drop off over distance, particularly near the system’s maximum range.
What is the difference between continuous and peak sound output?
Continuous power handling (RMS) is the measure of how much power a loudspeaker can handle for extended, continuous periods of use. Peak sound output measures bursts of power a loudspeaker can endure only momentarily.
What file formats can be played on the LRAD MP3 player?
- MP3: MPEG Layer-3 compression, all bit rates, stereo or mono.
- WAV: Uncompressed PCM (Pulse Code Modulation), all bit rates, stereo or mono.
- WMA: Windows Media Audio compression, all bit rates, stereo or mono.
How can I create my own LRAD voice messages and alert tones?
Messages can be created and played back on the fly using LRAD’s all-weather microphone and ruggedized, easy to use MP3 player. Also, most digital devices can be used to record and transfer customized voice communications and alert tones to the LRAD MP3 player.
What LRAD options and accessories are offered?
- Lightweight, high power searchlights (manually or remotely operated) (add link)
- Zoom cameras (do we want to include more information?) (add link)
- Wireless operation kits (add link)
- Multiple power options including AC, DC, portable battery packs, amplifiers and solar (add link)
- Mounting options (see Mounting Options FAQ) (add link)
- Remotely operated, full pan and tilt drives (add link)
- Trailers (add link)
What mounting options are available?
LRAD Corporation offers several temporary and permanent vehicle, vessel, building, tower and ground mounting options including:
- Vehicles: magnetic mounts and fastened custom mounts (add link or links to all options)
- Vessels: ship rail, roof, ASV and tripod mounts
- Buildings: roof, side and tripod mounts
- Towers: platform and tripod mounts
- Ground: trailer and tripod mounts
Are LRADs portable?
LRAD systems go anywhere communication is needed. From the hand portable LRAD 100X to larger systems temporarily or permanently mounted on stands, vehicles, trailers or helicopters.
Can LRADs be remotely operated?
Yes. The computer selected to remotely operate an LRAD requires the installation of LRAD software. After successful software installation, to connect and remotely operate the LRAD, the computer must use the same network subnet as the LRAD. For example, if the LRAD is set to 192.168.1.140, then the computer’s IP address must be set to 192.168.1.xxx, where xxx is any unused address on the network.
A remotely operated LRAD can take up to 30 seconds to fully boot. A series of beeps from the electronics enclosure followed by a clicking sound from the motors signals the LRAD is booting. The beeps and clicks can be difficult to hear, especially in noisy environments. Focus on listening for the clicking sound coming from the tilt motor assembly. The clicking sound indicates the motor brakes have cycled off/on, acknowledging the successful connection of all internal network devices. If the audible signals can’t be heard, waiting at least 30 seconds before launching the LRAD software should result in a successful boot. Attempting to run the LRAD software before an LRAD has fully powered up may cause unstable performance.
Can LRADs be integrated with other sensors to enhance perimeter security?
LRAD sensor options include zoom cameras, high-intensity searchlights and IP-addressable full pan and tilt drives for precise tracking and targeting. LRAD systems can also be integrated with radar, motion detectors and other sensors to provide fully automated security alerts and responses. By turning passive surveillance systems and command and control centers into remote first responders, LRAD provides a permanent perimeter presence, reduces false alarms and protects security personnel from potentially deadly situations.
Are LRADs Mil Standard?
LRAD acoustic hailing devices have been tested and approved by the U.S. Army and the U.S. Navy. LRAD systems operate in real world environments that include extreme heat, cold, moisture and dust. Materials and manufacturing of the highest standards ensures every LRAD performs reliably, even in the harshest conditions.
Are there export requirements for LRAD systems and accessories?
LRAD Corporation’s acoustic hailing devices and accessories do not require a license to export outside the United States. The Department of Commerce has classified them as an EAR99 product, which can be shipped NLR (“No License Required”). Similarly, the U.S. Department of State has determined that the Long Range Acoustic Device is not subject to the licensing jurisdiction of the Department of State.