Source components are vastly undervalued in most systems. Irrespective of how much you spend on an amplifier, or how good your loudspeakers are, unless you are feeding them a high quality signal you will never achieve the performance that they are capable of. There is an old saying – ‘rubbish in – rubbish out!’ – this is particularly true of your Hi-Fi or A/V system. This becomes more true as the ability of the system to resolve finer detail increases, be it audio or video.
As with most things it is important to strike a balance in your system. The quality of any one part of your system should not exceed any other. If it does your best component can only perform as well as the worst component will allow.