Why are you looking at a Dayton subwoofer, to mate with Wharfedale speakers.
Cut back on these expensive electronic things to save some money, and aim for
a different subwoofer
A nice receiver has a built in Amp and Dac (Denon, Marantz, Yamaha), and can
be found at AC4L.
Also do not get too carried away with fancy cables - that can/will sound as good
as some RadioShack cables - I only buy fancy cables on close-out pricing, if I am
concerned about looks (they can be foun at AC4L)
The all around good sound will come from speakers and subwoofer.