I have an M&K subwoofer which has a left(or mono) input and a right input. My receiver has an LFE output from the front channels, and I also have a Dolby Digital decoder that has an LFE out from the .1 channel. Am I correct that I should send both outputs to the subwoofer, the receiver out to the left and the decoder out to the right? I understand that in some cases the decoder .1 out is empty, so then the only LFE will come from the front channels. Is it possible that I will sometimes get an echo?
So George, you have a stereo receiver that has an LFE output which requires you to use a separate DD decoder? I don't recall ever seeing a non-surround receiver with an LFE out on it.
Anyway, I don't think you would blow up that M&K with both sending a signal, so I would try it and see if you get any feedback/echo with this set up. Before you send both signals into the M&K, I would also turn the volume down on the sub and inch it upward slowly for this experiment.