Last night for something to do I decided to play some low tones through my main speakers to see how low they would play. To my suprise the 10hz tone was easily audible. These are quite low end speakers by the way, with 6.5 inch drivers, so I am assuming the sound was more like a mechanical sound created by the cones moving... Am I right? Must be since a 10hz tone is definitely not audible. Does this mean my speakers are super cheap, or will other respectable speakers do the same thing? BTW. How do I measure the rolloff now?