If I set up my pre-pro with all speakers on large, sub on, filter set to 60 Hz and enhanced bass on I get the following before the signal gets to the ICBM-Front L x R have full range output, sub out is low pass @ 60 Hz. So far all is OK. Now if I set the ICBM to 60 Hz for the front L x R I understand that the frequencies below 60 Hz will go to the sub out on the ICBM. The LFE dial will control how much of the sub signal comming from the pre-pro will be added to the signal derived from the front's via the ICBM. My question is this-isn't this a problem to have 2 seperate filtered signals added together in this manner? Am I to understand that they will add with such precision as to not cause any distortion?