JH, higher maximum power capacity, regardless of whether the amplifier is in a receiver or is separate, becomes audibly significant only when the lower powered unit would audibly distort at the highest sound levels which the listener is using. Putting the amplifier in a separate box can in itself have no audible effect. So, in your case, unless you exceed the power capability of your 805(highly unlikely at safe listening levels)there would be no benefit to be noticed from a receiver amplifier or separate amplifier having a higher maximum power output rating.
