Simplex used Faraday bells, chimes, and horns in their fire alarm line from the late 70's up until the TrueAlert line came out in 1999. Good examples of this are their 2901-9838 and 2901-9833 horns, and the horn in their 4903-9219 horn/strobe. They also used Federal Vibratone 450s for their 2901-9806 horn, and Vibratone 350s for their 4040 horn.
As Brent mentioned, march time is controled on a fire alarm control panel, so any alarm, even a Wheelock 7002T who's horn skips when the strobe flashes, can do it (although it sounds very weird). Some electronic alarms, such as the Wheelock MT, can do march time on their own, and others, like a Smart Sync compatable Simplex TrueAlert, have to be hooked into a module to do it. Speakers can do what ever is played over them, most companies opt for a slow whoop and voice instructions.
As for the Simplex alarm you're talking about did it look like this?
if so it's a 4903 series, but the insides could be either an electric horn like a 9219 or 9403 (pictured), electronic like a 9422, or a speaker like a 9356. Good way to tell them apart is, if you look through the grill and see a shiny silver plate it's electric, if you see a small round black device it's electronic, if it lookes like the insides of a speaker (a round shiny middle on a flat black circle) is a speaker.
hope this helps somewhat
