pre-amp processor

I think the Lyngdorf is going to have much more flexibility in configuration.  The configuration settings in the Acurus ACT 4 are somewhat limited.  That being said, it is probably all about sound quality and I don't know that anyone here would have compared these two items side-by-side or at different times to give you an idea on the differences.

So, did some searching around.  I have never been able to find an internal pic of either of these processors, but it seems like there are a couple pages showing internal of the previous MP-50:

https://www.on-mag.fr/index.php/video-hd/tests-bancs-essai/18610-test-preampli-processeur-home-cinema-lyngdorf-mp-50-quand-le-home-cinema-rencontre-la-hifi-d-excellence

https://www.mjtaoyuansound.com.tw/news/68

Both pictures show that the Lyngdorf is run off a switching power supply.  This would be one reason I would avoid the Lyngdorf (even though many people rave about this processor).

Both the MP-50 and the new MP-60 are exactly 19lbs in weight, so I can only assume the MP-60 is also based on a switching power supply.

The Acurus ACT 4 is 25 lbs in weight.  Ah, here's a thread that has an internal pic:

https://www.avforums.com/threads/acurus-act-4-av-processor-review-comments.2179061/page-2

It seems the ACT 4 is also based on a switching power supply.  It's up to you, but at this point, I would not consider either processor.  I would probably go for the McIntosh MX-160 (which is a Lyngdorf digital processing platform with McIntosh linear power supplies and analog stages).

I know the previous McIntosh MX-160 used the Lyngdorf DSP and processing board, but used all McIntosh linear power supplies and audio stages.  The MX-170 probably uses the same architecture since it also includes RoomPerfect.  That's the way I would go if you have the budget (either used MX-160 or a new MX-170).

The Acurus is both hardware and software upgradeable I don’t think that the lyngdorf is and neither is McIntosh I don’t feel like having to buy new equipment every few years 

It sounds like you are putting upgrade features over sound quality.  If that's the direction you want to go, that's fine.  I would say the McIntosh MX-160 is still going to out-perform the newest Lyngdorf as far as sound quality goes.

I’m looking for sound quality along with 8k 2.1 hdmi 

or 4k with being able to upgrade to 8k

You could try looking into these two items:

NAD Masters M17 V2i (much lower price than your budget, but will likely have an 8K upgrade module in the future).

Theta Casablanca V - very expensive, but also will likely have an 8k upgrade in the future.

The problem here is wanting to be on the bleeding edge of technology but also expecting sound quality.