Ah, wasn't a Hoover my dad had, I think it might have been a bagless Electrolux "The Boss" model, the only real thing I remember about it was it had a terrible whine at a specific frequency from new, you could hear that thing throughout the whole house, really irritating sound... :\
But then, most modern high-wattage motors tend to have whines or squeals that really get my goat, cos I have rather sensitive hearing and certain frequencies, like those produced by cheap vac motors, physically hurt, which ain't nice... :S