ATI HPSS

In civil defense sirens, the ATI High-Power Speaker Station, by American Signal Corporation known as the ASC E-Class, is an electronic outdoor warning siren manufactured by Acoustic Technology, Inc that is used to alert citizens of air raids, and natural disasters.

Systems

The recent HPSS systems use high-powered electronic speakers, which can be independently arranged to provide directional or omnidirectional coverage, depending on installation. The HPSS16 have 4 speakers and the HPSS32 have 8 speakers. They can also be used as public announcement systems, and can play a number of programmed tones. Options include solar-powered operation pre-recorded voice messages. ATI also sold rotational units of the HPSS16, and HPSS32, called the "HPSS16R" and "HPSS32R", that are now discontinued.

Areas known to use HPSS systems

San Francisco, California - This system is unique featuring the sound of the decommissioned Federal Signal STL-10 sirens that the HPSS units replaced
Casitas Dam, Ventura, California - This system is unique as they look like the Federal Signal Directional Speaker Array sirens, but can have 7–8 speakers per stack, and gray caps on the speaker cones.
Indian Point Energy Center, New York
Owasso, Oklahoma had 16 ATI HPSS-32 sirens that were installed more than 20 years ago. In December 2023, all 16 HPSS-32 sirens were replaced with Whelen WPS-2910 omnidirectional sirens, and a 17th Whelen was installed near Stone Canyon Elementary.
Israel has 3,100 sirens as a part of its warning system, and 300 of them are HPSS32 sirens.
Sedgwick County, Kansas and the City of Wichita 27 ATI HPSS32 units are part of the system's 150 sirens.
Forsyth County, Georgia has mostly ATI hpss16r plus in 2012 added ATI HPSS32 this system back in 2008 replaced some Whelen 28X9 plus in 2022 they added more ATI HPSS-32's.
Norcross, Georgia has 10 ATI HPSS 16s that replaced Whelen 2805's, 2905's and one 2804. All were directly replaced in 2022.
Allen, Texas with 26 ATI HPSS-32 units.
Fort Riley, Kansas with 2 ATI HPSS-16 units.
Del City, Oklahoma with 8 ATI HPSS-16 units.
Malmstrom AFB, MT with 6 ATI HPSS-16 units.
Pasig, Philippines has 3 ATI HPSS-32 units.
Davao City, Philippines has at least 11 ATI HPSS-32 sirens around the city.
Battle Creek, Michigan has four rotating ATI HPSS-16R units. They run 575Hz alert for tornado warnings.
Menominee, Michigan has three rotating ATI HPSS-32R units
Pensacola NAS, Florida, ATI HPSS-16, the sirens on Pensacola's navy base are mostly used for tornado warnings and they play the colors in the morning and evening. When a warning is issued, these siren sound ATI's version of wail signal during tornado warnings. Attack signal or other signals have not been used yet. These siren are silently tested on Fridays.
University of West Florida In Pensacola, Florida, ATI HPSS-16 sirens here are used for chemical spills, weather warnings, lock downs, and they play the Westminster Chimes every day at noon.
Arnold, Missouri 7 ATI HPSS-32 units which replace the old Whelen WPS 3016 Sirens.
Ketchikan, Alaska maintains a system of 3 ATI HPSS-32 units which are tested audibly on the 15th of the month at noon. These sirens are used to warn for tsunamis or in the event of a dam failure.
Hudson County, New Jersey has an unknown number of HPSS sirens. They are supposedly used for nuclear emergencies.*
Chile, Antofagasta has also an unknown number of HPSS-32 sirens. They are used to warn about tsunamis and fires.
Sarnia, Ontario and the surrounding communities use a system of 22 ATI HPSS-32 units to warn of chemical plant spills and accidents, as well as severe weather. They are tested every Monday at 12:30PM. These replaced an older system of ACA Alertronic AL-6000R sirens.
Bandon, Oregon use 4 ATI HPSS-32's. They test every first Wednesday of the month at noon. These sirens are used to alert people of tsunamis. One of these ATIs replaced a Federal Signal Model 5.
Palo Verde Nuclear Generating Station, Wintersburg, Arizona use over 70 HPSS-32 sirens to warn the area in the event of a radiation release. Sirens are tested once a year in late November or early December.
Cannon Beach, Oregon Arch Cape, Oregon Has a system of 6 HPSS-32 sirens to alert the residents of a tsunami or more, replaced an older system of Whelen sirens of many kinds that played the sound of a cow mooing and a voice message for tests, new ATI system test with a hi-lo signal with a voice and mooing cow at the end. Tests every first Wednesday at noon.