I recall several of Ivan's rooms the mains were in front and the subs were closer to the listener and behind you.
I have both my subs about 10' closer to me and they seem to be very seamless, I would note I think it is easy to add to much bass. My concern is to make sure that the crossovers are low enough as to still blend with the mains and leave no gaps in lower crossover points.
I guess I can see this would be a bigger issue with mains that have a hard time getting down to save at least 60hz, that said I cross over one sub at 40hz and the other at 35hz to compensate for the room placement etc.
When you can crossover lover and with a steeper slope the bass is not very directional and that to seems to dismiss delays blending issues etc.
Good points, nice article and post... Thanks
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