I had the predecessor NAD C370 integrated amp / C540 cdp / C422 tuner driving different sets of quality-build floor and standmount speakers as a prior "B" system. I’ve also heard most of the recent models, so I know the NAD signature sound characteristics , strengths and warts, very well. This prior NAD gear speaker pairing included the TOTEM ARRO floorstanders; generally acknowledged as a nimble, forward, bright and transparent model in the TOTEM stable.
if you are looking for a a brighter and Improved audio presentation with a more enhanced upper midrange and top end, then move on from both:
(1) the NAD amp in favour of a quality built Euro integrated amp, and also
(2) an improved source instead of the OPPO,
instead of just new speakers.
(1) In brief, the NAD electronics present
(i) a comparatively "darker" overall and
(ii) a rolled off top end
audio signature.
(2) WRT the OPPO, I ran the top CAMBRIDGE Bluray player as a discrete stand-alone BluRay player for HT. (NOTE: The OPPO and CAMBRIDGE share the same motherboard made by the same company and also made in the same plant.) For HT multi-channel movies soundtracks and manufactured multi-channel audio, the CAMBRIDGE player did fine yeoman work in that role.....
BUT -- and it’s a big "BUT" --
it could not compete with my discrete stand-alone quality build high-end CDP/DAC for my 2-channel audio music performance requirements .... Not even close.
Your takeaway FWIW:
Going to different floor-standers with the same NAD integrated amp and the OPPO spinner won’t get to the Emerald City in OZ because of these inescapable NAD and OPPO sonic signature traits.
if you are looking for a a brighter and Improved audio presentation with a more enhanced upper midrange and top end, then move on from both:
(1) the NAD amp in favour of a quality built Euro integrated amp, and also
(2) an improved source instead of the OPPO,
instead of just new speakers.
(1) In brief, the NAD electronics present
(i) a comparatively "darker" overall and
(ii) a rolled off top end
audio signature.
(2) WRT the OPPO, I ran the top CAMBRIDGE Bluray player as a discrete stand-alone BluRay player for HT. (NOTE: The OPPO and CAMBRIDGE share the same motherboard made by the same company and also made in the same plant.) For HT multi-channel movies soundtracks and manufactured multi-channel audio, the CAMBRIDGE player did fine yeoman work in that role.....
BUT -- and it’s a big "BUT" --
it could not compete with my discrete stand-alone quality build high-end CDP/DAC for my 2-channel audio music performance requirements .... Not even close.
Your takeaway FWIW:
Going to different floor-standers with the same NAD integrated amp and the OPPO spinner won’t get to the Emerald City in OZ because of these inescapable NAD and OPPO sonic signature traits.