Need new amp...

Schiit Audio Vidar amp (or two in mono) I believe they are $699usd and get great reviews, the lower powered Aegir amp just got Stereophile class A recommendation, and maybe a Freya  preamp too would be a nice addition. 

would be a great system and potentially better then both the NAD and Cambridge. And less money made in USA too. 

https://www.schiit.com/products/vidar

https://www.schiit.com/

I use one of their DAC's and am very happy with the service and quality of product. 

Schiit Audio Vidar amp (or two in mono) I believe they are $699usd and get great reviews, the lower powered Aegir amp just got Stereophile class A recommendation, and maybe a Freya preamp too would be a nice
addition.

I checked out the Vidar amp, and I am unfamiliar with class AB because I normally only see A and/or B. Nonetheless, it seems like AB still retains high quality sound. 

Mono at 400w for only $700?? My speakers take 200w continous with peaks to 800w or 1000w (different sources have different specs cuz the speakers are old so i'm not sure between 800/1000). The fact that I can get two of these amps for $1400 and push out 800w continuous just seems absurd for that price tag. Is there some drawback I am missing because the reviews all glorify this amp.

As for the preamp recommendation, the NAD C 658 is a streamer/dac/preamp combo, so do you recommend getting a different product for my dac/preamp needs? (I don't actually need the streamer part, just a nice feature I can use)

Thank you for your help!

EDIT: Going with option 1

There's a used AVA Fet Valve 400R power amp right now on Audiogon; asking price $1500. This is a really nice amp, and because AVA products don't have as great resale value as some of the better-known brands, it's a bargain. There was a review of the 600R in TAS that raved about it; the two are supposed to sound the same, except for higher power in the 600R.

I would get a gently used something..