Regarding speaker sizes: my understanding based on something (heaven knows what) I've read in the distant past was that your receiver handles bass in one of two ways based on set speaker sizes. If front L and R are set to small, no frequency below the crossover point is sent to those channels. If front L and R are set to large, frequencies below the crossover point are sent to both the front L and R AND the LFE channel....
Close, but not quite.
Here is the jist of it:
Main speakers set to small - All info from channels 1 and 2 (call these the main R&L channels) below the crossover point is sent to the sub, along with LFE (.1) channel information.
Main speakers set to large - All info in channels 1 and 2 is sent to R&L mains, period, regardless of crossover setting. Sub plays only LFE channel.
Main speakers set to large with "double bass" setting - All information in channels 1 and 2 is sent to R&L mains. Information below the crossover point is ALSO sent to the sub, along with the LFE channel. If, for example you have the mains set at 60 hz, both the sub and mains will be receiving all channel 1 and 2 info below 60 hz.
EDIT: If the double bass setting sounds best, by all means go ahead and use it. I think you would be better off with the crossover at 60 - 80 hz as opposed to 100 though, the M60's will handle that range with ease. Personally I only have little W22's and I have them set at 90 hz, and they won't go nearly as low as the M60's.
