randog,
the ICBM passes the signal it receives on it's LFE input straight through, without applying any of its internal crossovers. this allows you to set up the sub for both 2channel and HT.
in the processor, with speakers set to "small", all the bass below the crossover + the discrete LFE channel bass is sent through the processors LFE pre-out. This then goes to the LFE input on the ICBM and then out to the sub.
the information above the crossover is sent from the main preouts to the pre-amp bypass input. Pre-amp output one goes to the main amp (this signal is > 80hz only as it has already been subjected to the crossover in the processor) and pre-amp output two goes to the L/R inputs on the ICBM and out to the sub, but this is mainly irrelevant for movies since very little < 80hz information is left in this part of the signal...only that which is left over due to the slope of the crossover in the processor.
for two channel, it is much simpler. One preamp output goes directly to the main amp, full-range. the 2nd output goes to the ICBM L/R inputs, is filtered, and sent to the sub.
hope this makes sense
