I was wondering about this. Should I use the passive crossover on my PE 250W amp, or should I get an active crossover? My system uses MartinLogan Scenarios, an Adcom GFA-5400 amp, Luxman CD player, and a Tempest Adire Alignment sub. I was wondering if I should get an external crossover, and which! I can't find any good ones. If there is one, by any chance, can I find it in New York? I'll be there next week... TIA!