What is the difference between a Model 5 and a Model 7?

[sirendude2012]

Do a 12-port Model 5 and a 12-port Model 7 sound any different?

No. They are the same siren internally, they should sound the same.

I hear the Model 7 has a faster windup than the Model 5. Is that true?

They are the same siren internally. Meaning they have the same motor. If they are hooked up to 480 volts, they will wind up faster. 240 or 208 will result in slower.