B&W 803 D3 speakers - which amp?

Hello,

i have similar arrangement but I do not think I am getting the best of the speakers.
I have 4 x b&w 803 d3 + centre and currently all this is run by Arcam 850

could you please suggest how to improve sound ?
Would it be a good idea to buy Classé 5300 and then look for another processor ? Can I use my old Arcam and add the Classé as an amplifier only ? 
Maybe it is possible to add powerful stereo amp to fronts and adjust Arcam to only rear and centre ?

Any advice would be appreciated

tom

You guys are forgetting an amp that was built to power b&w 801s rha electrocompaniet Nemo endvits more affordable cousin the aw400.monoblocks

The power delivery of these amps are massivePush-pull, solid-state, monoblock amplifier. Output power: 400Wpc into 8 ohms (26dBW), 765Wpc into 4 ohms (25.2dBW), 1010Wpc

Dava and Troy
Audio intellect

I have mine hooked to a McIntosh MA352, plenty power without the even slightest hint of weakness or dynamics. That's if you're into hybrid solid-state and tube amp designs, but it's very modern looking yet retro for 2020.

In a way it matches the goal of the B&W. Paying homage to their history, yet updated for the modern generation.