active and passive subwoofer's

[saprano]

I stumble upon this article on avs http://www.avsforum.com/avs-vb/showthread.php?t=985964 so i already know the differince between the two, but how can i tell if mine is active or passive?. i just picked up this definitive tech sub today, http://www.definitivetech.com/dealer...000_noback.jpg ,
and here you can read the specs on it if you scroll to the bottom http://www.definitivetech.com/loudsp...nema_1000.html ,but it doesint say anything about it being active or passive so does anybody know from reading those specs what kind do i have?

another question, ill be using the lfe input on the sub so do i have to play around with the crossover freqency or does the amp take care of that? i read somewere that if using a lfe input there's no need to adjust the freqency? if i do have to adjust it what hz should i set in on?.