It would be interesting to take a decent active system, something that would rate well in the traditional Iasca competitions, give it a listen. Now with the crossover, low pass the system at 20K. Would it sound different, I think it would. Does anyone want to give this a try?

 

That's a great idea though I don't think there will be any audible difference. If there is a phase shift induced below 20k some listeners might "sense a disturbance in the phase"

Thanks everyone, I'm here all week...