Now, I'm confused.

Anybody remember the AudioPulse reverberation device? It allowed one to dial in various settings: "small club" all the way up to "cathedral"! It contained a two-channel amp to be connected to a pair of speakers behind the listener. And it gave surprisingly good results when used judiciously! This was back in the mid-70's before HT. 

The soundstage consists of width and depth. That's why room treatments are being recommended. Using absorbtion and/or diffusion panels will help shape the soundstage and focus the image.

Regarding a preamp, the Schiit Freya may be worth an audition due to the use of the 6SN7 tube, plus a return policy.

dude !!!!!
pretty sure my Dad had a 1965 Dual 1019
with a V15 Type II

and i am not knocking it...

i think you have been given excellent advice to download tge model 2 manual for free and rigorous setup by the book. I assume you have tge Soundanchor stands ?

after you get that squared away ( not literally ) then perhaps consider some of the gear listed above.....

as some have said without knowing what cartridge you are running in the German semiautomic stacker, I would advise a preamp change...

we were one of the biggest NAD dealers in America, I know the...he&& still have a 3020 a in the garage....

I have an ADCOM, GFA-5500 and run it with a vintage Audible Illusions, Modules II, tubed, pre amp. The combination, for the $, presents a very nice - wide, deep and detailed - sound stage. One thing to note - the ADCOMs, like many other SS amps, need several hrs. of warm up to sound their best..Jim