What exactly is different in your set up to the store you listened at? If you purchased all the named items from them (Spendor, Hegel, Bluesound, Vovox), I’d look at everything else first. If the dealer has/had the same set-up I’d think they’d have the best suggestion as to where to start, but your room (over or under-damped), speaker placement, ’clean’ power & your cables are all going to be--and remain--influences regardless of what else you change.