Hi, I am assuming that your receiver has a pre-out/in jack, so you can use it as a preamp, and bypass the power amp section. My NAD 320 integrated does. Just remove the out/in jumpers and use the pre out for the amp. (By the way, for right now try removing the receiver jumpers and using a short interconnect instead, it makes a huge difference, the NAD brass jumpers kill the sound.)
I have found NAD preamp sections to be very good, actually, far better than the amps IMHO. Although who knows with a receiver where corners are cut. I think your system would sound great with the new amp, and you can always sell the SF amp if you don't like it for some reason. You have to buy something first, right? I like your approach of buying one quality item at a time. Paradigm monitor speakers are capable of really excellent sound with good gear.
I would get the amp, next look into a better CD player, maybe used. I swapped my NAD 542 for a Jolida JD 100 Tube CD and was amazed. Of course your plan begs the question of why not just get a tube integrated amp, of which there are many for the price of a used SF Power 1, but for me separates are superior ultimately. I think a used tube integrated would improve your sound much more, for the same money as the Power 1.
I have found NAD preamp sections to be very good, actually, far better than the amps IMHO. Although who knows with a receiver where corners are cut. I think your system would sound great with the new amp, and you can always sell the SF amp if you don't like it for some reason. You have to buy something first, right? I like your approach of buying one quality item at a time. Paradigm monitor speakers are capable of really excellent sound with good gear.
I would get the amp, next look into a better CD player, maybe used. I swapped my NAD 542 for a Jolida JD 100 Tube CD and was amazed. Of course your plan begs the question of why not just get a tube integrated amp, of which there are many for the price of a used SF Power 1, but for me separates are superior ultimately. I think a used tube integrated would improve your sound much more, for the same money as the Power 1.