Something is missing

Synergistic Research Orange fuses, ECT, and HFT will bring your system alive. Perfect Path Solutions Total Contact will reveal inner detail like you never imagined was even there. Altogether these will set you back around $1500 and deliver more improvement than any component you currently have.

Describe your room and the speaker placement??

Room is about 18 wide and 35 long  sitting position is about 12 back with speakers 12 apart and toed in slightly. I did hook up a pair of REL S3 subs. But still did not fix to my liking floor is hardwood

Jim Smiths excellent book on getting better sound

Don’t go the fuse route. That isn’t your problem. That would be the last thing to upgrade when you have money to burn/throw away.

You can get better sound by connecting a good external DAC to the Z1.  Also, I had the same Rotel that you have and wasn't impressed with the sound and sold it.  That may not be your problem though as many people are very happy with it.