Alright, so the upgrade is complete and I've got to say the whole package seems complete (for now...)
I first hooked the nad to my existing set up, what I noticed: some records seemed much clearer, but didn't seem to have as much output as before, and other records just sounded off. It was funny because those that seemed best on the old setup (electronica, dub-reggae) were the ones that sounded off, especially as the volume was turned up. But some of the jazz records were nice and crisp, but still didn't sound as good at moderate volumes. Guess that was the quality of the yamaha and radio shack making them selves obvious.
Well thanks to Pumkinman all that changed. He shipped me a Onkyo m-501 and a NAD 1600. So now my system is:
NAD 1600 preamp
NAD 533 turntable
Onkyo m-501 amp
Linn Keilidh loudspeakers in rosenut
So far everything I've played from my collection sounds worlds better, particularly anything that has quality production behind it. I was a little concerned about finding a combination that would be a benefit to all the music types I like, but the Clash to Johnny Cash, Art Blakey to Dolly Parton (that's my wife's) all's been great so far.
One question, what's the theory behind the loudness setting on the preamp. Seems its beneficial to some of the rock and punk, but totally blows out levels on the crisp and sparse type stuff.
And what's the next step - speaker cables, interconnects, record cleaning???