If I had left the input leads a bit longer that last pair I just built, I'd pull the network and try this, next ones I'll leave the input wires logner so it's simple to pull the networks out.
Jeremy, are your cabinets lined with no rez ( sorry can't remember) ? Have always used it the Encore kits I've built and bass has always been very goo, clean and quite punchy actually, I've definitely never found it to be boomy although this could be a bit room dependent I suppose
A $.20 resistor is a lot cheaper than a sheet of no rez, but, if your cabinets are not lined with it, you really shold give it a try.
jay