Regarding the Touchmaster sirens except for the Delta models, the pitch and rise and fall rate of the wail changed around the year 2000. The yelp pitch and rate did not change.
Regarding the 80K sirens, yes they can be used with any Unitrol brand controller or even an aftermarket. The 80K is...
Have to agree with Wailer on this. The older Federal Interceptor series 2D or Director series 1D have the nostalgic slower lower pitched wail and yelp sounds. Also the old SP and Dietz brand sirens had great low tones.
I've been running Unitrol sirens for 30+ years. They are best sounding sirens out there in my opinion and the original Touchmasters, Omegas and 80K's are extremely reliable. Sorry to hear that Federal is doing this but I wasn't a big fan of Unitrol being bought out by them years ago.