San Francisco police officer Rich Lee vividly remembers the first time he tested the Rumbler in real traffic conditions. It was a day when the manufacturer, Federal Signal, was in town to show off the ...

A new type of audible notification signal was introduced in the 2012 version of NFPA 72 that employs a low-frequency sound — in the 520 Hz range — when appliances are installed where people sleep. If ...

Lifetone Technology is recalling 10,000 HLAC151 Bedside Fire Alarm and Clocks due to a failure to fully alert those who have the alarms. The defective units sound a low-frequency audio signal and ...

Hot on the heels of DIRAC's announcement regarding their Active Room Treatment (ART) approach, Trinnov has introduced their WaveForming technology, which presents remarkably similar claims and ...

Every stereo system could probably benefit from the addition of a subwoofer to it. But is it really worth the cost to add one to your specific setup? Subwoofers are a special type of speaker capable ...

I used to be able to hear 3kHz easily but as my hair cells fade into the sunset that frequency now seems to be down 3 or 6 dB. As a consequence the high pitched "beep beep" sound on my portable alarm ...